diff --git a/packages/ast-spec/src/base/ClassBase.ts b/packages/ast-spec/src/base/ClassBase.ts
new file mode 100644
index 00000000000..4878cfc87b6
--- /dev/null
+++ b/packages/ast-spec/src/base/ClassBase.ts
@@ -0,0 +1,70 @@
+import type { Identifier } from '../expression/Identifier/spec';
+import type { ClassBody } from '../special/ClassBody/spec';
+import type { Decorator } from '../special/Decorator/spec';
+import type { TSClassImplements } from '../special/TSClassImplements/spec';
+import type { TSTypeParameterDeclaration } from '../special/TSTypeParameterDeclaration/spec';
+import type { TSTypeParameterInstantiation } from '../special/TSTypeParameterInstantiation/spec';
+import type { LeftHandSideExpression } from '../unions/LeftHandSideExpression';
+import type { BaseNode } from './BaseNode';
+
+export interface ClassBase extends BaseNode {
+  /**
+   * Whether the class is an abstract class.
+   * ```
+   * abstract class Foo {...}
+   * ```
+   * This is always `undefined` for `ClassExpression`.
+   */
+  // TODO(#5020) - make this `false` if it is not `abstract`
+  abstract?: boolean;
+  /**
+   * The class body.
+   */
+  body: ClassBody;
+  /**
+   * Whether the class has been `declare`d:
+   * ```
+   * declare class Foo {...}
+   * ```
+   * This is always `undefined` for `ClassExpression`.
+   */
+  // TODO(#5020) - make this `false` if it is not `declare`d
+  declare?: boolean;
+  /**
+   * The decorators declared for the class.
+   * This is `undefined` if there are no decorators.
+   * ```
+   * @deco
+   * class Foo {...}
+   * ```
+   * This is always `undefined` for `ClassExpression`.
+   */
+  // TODO(#5020) - make this an empty array if there are none declared
+  decorators?: Decorator[];
+  /**
+   * The class's name.
+   * - For a `ClassExpression` this may be `null` if the name is omitted.
+   * - For a `ClassDeclaration` this may be `null` if and only if the parent is
+   *   an `ExportDefaultDeclaration`.
+   */
+  id: Identifier | null;
+  /**
+   * The implemented interfaces for the class.
+   * This is `undefined` if there are no implemented interfaces.
+   */
+  implements?: TSClassImplements[];
+  /**
+   * The super class this class extends.
+   */
+  superClass: LeftHandSideExpression | null;
+  /**
+   * The generic type parameters passed to the superClass.
+   * This is `undefined` if there are no generic type parameters passed.
+   */
+  superTypeParameters?: TSTypeParameterInstantiation;
+  /**
+   * The generic type parameters declared for the class.
+   * This is `undefined` if there are no generic type parameters declared.
+   */
+  typeParameters?: TSTypeParameterDeclaration;
+}
diff --git a/packages/ast-spec/src/base/ClassDeclarationBase.ts b/packages/ast-spec/src/base/ClassDeclarationBase.ts
deleted file mode 100644
index f104b739b51..00000000000
--- a/packages/ast-spec/src/base/ClassDeclarationBase.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-import type { Identifier } from '../expression/Identifier/spec';
-import type { ClassBody } from '../special/ClassBody/spec';
-import type { Decorator } from '../special/Decorator/spec';
-import type { TSClassImplements } from '../special/TSClassImplements/spec';
-import type { TSTypeParameterDeclaration } from '../special/TSTypeParameterDeclaration/spec';
-import type { TSTypeParameterInstantiation } from '../special/TSTypeParameterInstantiation/spec';
-import type { LeftHandSideExpression } from '../unions/LeftHandSideExpression';
-import type { BaseNode } from './BaseNode';
-
-export interface ClassDeclarationBase extends BaseNode {
-  typeParameters?: TSTypeParameterDeclaration;
-  superTypeParameters?: TSTypeParameterInstantiation;
-  id: Identifier | null;
-  body: ClassBody;
-  superClass: LeftHandSideExpression | null;
-  implements?: TSClassImplements[];
-  abstract?: boolean;
-  declare?: boolean;
-  decorators?: Decorator[];
-}
diff --git a/packages/ast-spec/src/base/FunctionBase.ts b/packages/ast-spec/src/base/FunctionBase.ts
new file mode 100644
index 00000000000..56446bc78ba
--- /dev/null
+++ b/packages/ast-spec/src/base/FunctionBase.ts
@@ -0,0 +1,74 @@
+import type { Identifier } from '../expression/Identifier/spec';
+import type { TSTypeAnnotation } from '../special/TSTypeAnnotation/spec';
+import type { TSTypeParameterDeclaration } from '../special/TSTypeParameterDeclaration/spec';
+import type { BlockStatement } from '../statement/BlockStatement/spec';
+import type { Expression } from '../unions/Expression';
+import type { Parameter } from '../unions/Parameter';
+import type { BaseNode } from './BaseNode';
+
+export interface FunctionBase extends BaseNode {
+  /**
+   * Whether the function is async:
+   * ```
+   * async function foo(...) {...}
+   * const x = async function (...) {...}
+   * const x = async (...) => {...}
+   * ```
+   */
+  async: boolean;
+  /**
+   * The body of the function.
+   * - For an `ArrowFunctionExpression` this may be an `Expression` or `BlockStatement`.
+   * - For a `FunctionDeclaration` or `FunctionExpression` this is always a `BlockStatement.
+   * - For a `TSDeclareFunction` this is always `undefined`.
+   * - For a `TSEmptyBodyFunctionExpression` this is always `null`.
+   */
+  body?: BlockStatement | Expression | null;
+  /**
+   * This is only `true` if and only if the node is a `TSDeclareFunction` and it has `declare`:
+   * ```
+   * declare function foo(...) {...}
+   * ```
+   */
+  // TODO(#5020) - make this always `false` if it is not `declare`d instead of `undefined`
+  declare?: boolean;
+  /**
+   * This is only ever `true` if and only the node is an `ArrowFunctionExpression` and the body
+   * is an expression:
+   * ```
+   * (() => 1)
+   * ```
+   */
+  expression: boolean;
+  /**
+   * Whether the function is a generator function:
+   * ```
+   * function *foo(...) {...}
+   * const x = function *(...) {...}
+   * ```
+   * This is always `false` for arrow functions as they cannot be generators.
+   */
+  generator: boolean;
+  /**
+   * The function's name.
+   * - For an `ArrowFunctionExpression` this is always `null`.
+   * - For a `FunctionExpression` this may be `null` if the name is omitted.
+   * - For a `FunctionDeclaration` or `TSDeclareFunction` this may be `null` if
+   *   and only if the parent is an `ExportDefaultDeclaration`.
+   */
+  id: Identifier | null;
+  /**
+   * The list of parameters declared for the function.
+   */
+  params: Parameter[];
+  /**
+   * The return type annotation for the function.
+   * This is `undefined` if there is no return type declared.
+   */
+  returnType?: TSTypeAnnotation;
+  /**
+   * The generic type parameter declaration for the function.
+   * This is `undefined` if there are no generic type parameters declared.
+   */
+  typeParameters?: TSTypeParameterDeclaration;
+}
diff --git a/packages/ast-spec/src/base/FunctionDeclarationBase.ts b/packages/ast-spec/src/base/FunctionDeclarationBase.ts
deleted file mode 100644
index 50b7aa97bf2..00000000000
--- a/packages/ast-spec/src/base/FunctionDeclarationBase.ts
+++ /dev/null
@@ -1,18 +0,0 @@
-import type { Identifier } from '../expression/Identifier/spec';
-import type { TSTypeAnnotation } from '../special/TSTypeAnnotation/spec';
-import type { TSTypeParameterDeclaration } from '../special/TSTypeParameterDeclaration/spec';
-import type { BlockStatement } from '../statement/BlockStatement/spec';
-import type { Parameter } from '../unions/Parameter';
-import type { BaseNode } from './BaseNode';
-
-export interface FunctionDeclarationBase extends BaseNode {
-  id: Identifier | null;
-  generator: boolean;
-  expression: boolean;
-  async: boolean;
-  params: Parameter[];
-  body?: BlockStatement | null;
-  returnType?: TSTypeAnnotation;
-  typeParameters?: TSTypeParameterDeclaration;
-  declare?: boolean;
-}
diff --git a/packages/ast-spec/src/base/TSHeritageBase.ts b/packages/ast-spec/src/base/TSHeritageBase.ts
index 5c20542e4f9..683600ec01d 100644
--- a/packages/ast-spec/src/base/TSHeritageBase.ts
+++ b/packages/ast-spec/src/base/TSHeritageBase.ts
@@ -3,7 +3,7 @@ import type { Expression } from '../unions/Expression';
 import type { BaseNode } from './BaseNode';
 
 export interface TSHeritageBase extends BaseNode {
-  // TODO(error handling) - this should be restricted to MemberExpression | Identifier
+  // TODO(#1852) - this should be restricted to MemberExpression | Identifier
   expression: Expression;
   typeParameters?: TSTypeParameterInstantiation;
 }
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/fixture.ts
similarity index 100%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/fixture.ts
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/fixture.ts
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..c17328b32e8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ missing-body TSESTree - Error 1`] = `[TSError: '{' expected.]`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..4f8ef959d9b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ missing-body Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:9)]`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..18e4442401e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-body/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ missing-body Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/fixture.ts
new file mode 100644
index 00000000000..83ffb99a72b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/fixture.ts
@@ -0,0 +1 @@
+class C extends D<> {}
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..4f99d71eb95
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ missing-extends-type-param TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..f8435732131
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ missing-extends-type-param Babel - Error 1`] = `[SyntaxError: Type argument list cannot be empty. (1:17)]`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..35683b84121
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ missing-extends-type-param Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/fixture.ts
new file mode 100644
index 00000000000..4f3d75967f9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/fixture.ts
@@ -0,0 +1 @@
+class C<> {}
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..9682f9c4373
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ missing-type-param TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..a14c3c54cac
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ missing-type-param Babel - Error 1`] = `[SyntaxError: Type parameter list cannot be empty. (1:7)]`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..49567ea7a7b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ missing-type-param Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/1-TSESTree-Error.shot
deleted file mode 100644
index 30525843580..00000000000
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/1-TSESTree-Error.shot
+++ /dev/null
@@ -1,3 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`AST Fixtures declaration ClassDeclaration _error_ no-body TSESTree - Error 1`] = `[TSError: '{' expected.]`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/2-Babel-Error.shot
deleted file mode 100644
index e72c371e842..00000000000
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/2-Babel-Error.shot
+++ /dev/null
@@ -1,3 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`AST Fixtures declaration ClassDeclaration _error_ no-body Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:9)]`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/3-Alignment-Error.shot
deleted file mode 100644
index b6946023222..00000000000
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/3-Alignment-Error.shot
+++ /dev/null
@@ -1,3 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`AST Fixtures declaration ClassDeclaration _error_ no-body Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/fixture.ts
new file mode 100644
index 00000000000..383479818e6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/fixture.ts
@@ -0,0 +1 @@
+class C<1> {}
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..0be64ad3473
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ non-identifier-type-param TSESTree - Error 1`] = `[TSError: Type parameter declaration expected.]`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..6ef9a4c481a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ non-identifier-type-param Babel - Error 1`] = `[SyntaxError: Unexpected token (1:8)]`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..98c58289073
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ non-identifier-type-param Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/fixture.ts
similarity index 100%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/fixture.ts
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/fixture.ts
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/1-TSESTree-AST.shot
similarity index 95%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/1-TSESTree-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/1-TSESTree-AST.shot
index ab7726fcd52..7f37d13c488 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/1-TSESTree-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/1-TSESTree-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorMany TSESTree - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-many TSESTree - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/2-TSESTree-Tokens.shot
similarity index 94%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/2-TSESTree-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/2-TSESTree-Tokens.shot
index f406c812335..5f64c50c3bd 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/2-TSESTree-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/2-TSESTree-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorMany TSESTree - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-many TSESTree - Tokens 1`] = `
 Array [
   Punctuator {
     type: "Punctuator",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/3-Babel-AST.shot
similarity index 95%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/3-Babel-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/3-Babel-AST.shot
index 60af58e326d..3c94fd556d0 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/3-Babel-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/3-Babel-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorMany Babel - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-many Babel - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/4-Babel-Tokens.shot
similarity index 94%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/4-Babel-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/4-Babel-Tokens.shot
index 888d2f213d3..e7d7dba3776 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/4-Babel-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/4-Babel-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorMany Babel - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-many Babel - Tokens 1`] = `
 Array [
   Punctuator {
     type: "Punctuator",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..751a6cc951f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration decorator-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..338a8838194
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration decorator-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/fixture.ts
similarity index 100%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/fixture.ts
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/fixture.ts
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/1-TSESTree-AST.shot
similarity index 93%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/1-TSESTree-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/1-TSESTree-AST.shot
index f0550dcabbe..aba5fc9308d 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/1-TSESTree-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/1-TSESTree-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorOne TSESTree - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-one TSESTree - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/2-TSESTree-Tokens.shot
similarity index 92%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/2-TSESTree-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/2-TSESTree-Tokens.shot
index 7354a4e9bfe..7d75dd27790 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/2-TSESTree-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/2-TSESTree-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorOne TSESTree - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-one TSESTree - Tokens 1`] = `
 Array [
   Punctuator {
     type: "Punctuator",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/3-Babel-AST.shot
similarity index 94%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/3-Babel-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/3-Babel-AST.shot
index f2e4581ba58..9f91cb39e80 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/3-Babel-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/3-Babel-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorOne Babel - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-one Babel - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/4-Babel-Tokens.shot
similarity index 92%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/4-Babel-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/4-Babel-Tokens.shot
index eb1816cba73..3b6aa60b33d 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/4-Babel-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/4-Babel-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorOne Babel - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-one Babel - Tokens 1`] = `
 Array [
   Punctuator {
     type: "Punctuator",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/5-AST-Alignment-AST.shot
similarity index 68%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/5-AST-Alignment-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/5-AST-Alignment-AST.shot
index 97881c1404c..503bd4f5ad8 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/5-AST-Alignment-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/5-AST-Alignment-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorMany AST Alignment - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-one AST Alignment - AST 1`] = `
 "Snapshot Diff:
 Compared values have no visual difference."
 `;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/6-AST-Alignment-Tokens.shot
similarity index 68%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/6-AST-Alignment-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/6-AST-Alignment-Tokens.shot
index e57e9fa7313..1ab8923d733 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorMany/snapshots/6-AST-Alignment-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decorator-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorMany AST Alignment - Token 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration decorator-one AST Alignment - Token 1`] = `
 "Snapshot Diff:
 Compared values have no visual difference."
 `;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/fixture.ts
similarity index 100%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/fixture.ts
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/fixture.ts
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/1-TSESTree-AST.shot
similarity index 97%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/1-TSESTree-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/1-TSESTree-AST.shot
index da9fc3ba5ca..43fbb02d6c0 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/1-TSESTree-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/1-TSESTree-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration extends-type-parameters TSESTree - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration extends-type-param TSESTree - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/2-TSESTree-Tokens.shot
similarity index 97%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/2-TSESTree-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/2-TSESTree-Tokens.shot
index 3eb2b515a24..c0ea9a80846 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/2-TSESTree-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/2-TSESTree-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration extends-type-parameters TSESTree - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration extends-type-param TSESTree - Tokens 1`] = `
 Array [
   Keyword {
     type: "Keyword",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/3-Babel-AST.shot
similarity index 98%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/3-Babel-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/3-Babel-AST.shot
index 8f9634b6629..2071afa4c8e 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/3-Babel-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/3-Babel-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration extends-type-parameters Babel - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration extends-type-param Babel - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/4-Babel-Tokens.shot
similarity index 98%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/4-Babel-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/4-Babel-Tokens.shot
index db93259e13a..a19207090a5 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/4-Babel-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/4-Babel-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration extends-type-parameters Babel - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration extends-type-param Babel - Tokens 1`] = `
 Array [
   Keyword {
     type: "Keyword",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/5-AST-Alignment-AST.shot
similarity index 81%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/5-AST-Alignment-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/5-AST-Alignment-AST.shot
index 17f60ddc36a..d7a16a19520 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/5-AST-Alignment-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/5-AST-Alignment-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration extends-type-parameters AST Alignment - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration extends-type-param AST Alignment - AST 1`] = `
 "Snapshot Diff:
 Compared values have no visual difference."
 `;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/6-AST-Alignment-Tokens.shot
similarity index 80%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/6-AST-Alignment-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/6-AST-Alignment-Tokens.shot
index 8c6277e35df..e231ba6210a 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-parameters/snapshots/6-AST-Alignment-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/extends-type-param/snapshots/6-AST-Alignment-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration extends-type-parameters AST Alignment - Token 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration extends-type-param AST Alignment - Token 1`] = `
 "Snapshot Diff:
 Compared values have no visual difference."
 `;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/fixture.ts
similarity index 100%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/fixture.ts
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/fixture.ts
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/1-TSESTree-AST.shot
similarity index 94%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/1-TSESTree-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/1-TSESTree-AST.shot
index 09fb61990bf..13f2fe48ba0 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/1-TSESTree-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/1-TSESTree-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters TSESTree - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-param TSESTree - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/2-TSESTree-Tokens.shot
similarity index 93%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/2-TSESTree-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/2-TSESTree-Tokens.shot
index 7afa2b8839b..4b814b82829 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/2-TSESTree-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/2-TSESTree-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters TSESTree - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-param TSESTree - Tokens 1`] = `
 Array [
   Keyword {
     type: "Keyword",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/3-Babel-AST.shot
similarity index 94%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/3-Babel-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/3-Babel-AST.shot
index de9ab22cc6b..288661b1311 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/3-Babel-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/3-Babel-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters Babel - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-param Babel - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/4-Babel-Tokens.shot
similarity index 93%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/4-Babel-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/4-Babel-Tokens.shot
index 89bca663a6d..27db70bb89e 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/4-Babel-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/4-Babel-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters Babel - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-param Babel - Tokens 1`] = `
 Array [
   Keyword {
     type: "Keyword",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/5-AST-Alignment-AST.shot
similarity index 95%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/5-AST-Alignment-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/5-AST-Alignment-AST.shot
index 2dd40abc556..0ee9dbba035 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/5-AST-Alignment-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/5-AST-Alignment-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters AST Alignment - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-param AST Alignment - AST 1`] = `
 "Snapshot Diff:
 - TSESTree
 + Babel
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..581d856705d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-param/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration type-param AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/fixture.ts
similarity index 100%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/fixture.ts
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/fixture.ts
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/1-TSESTree-AST.shot
similarity index 98%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/1-TSESTree-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/1-TSESTree-AST.shot
index c3bf9660d6d..aac248040d8 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/1-TSESTree-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/1-TSESTree-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-parameters TSESTree - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-param TSESTree - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/2-TSESTree-Tokens.shot
similarity index 97%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/2-TSESTree-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/2-TSESTree-Tokens.shot
index f73a167dba3..f697768aad0 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/2-TSESTree-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/2-TSESTree-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-parameters TSESTree - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-param TSESTree - Tokens 1`] = `
 Array [
   Keyword {
     type: "Keyword",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/3-Babel-AST.shot
similarity index 98%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/3-Babel-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/3-Babel-AST.shot
index 7c5a5149bbe..e5856d26fbc 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/3-Babel-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/3-Babel-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-parameters Babel - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-param Babel - AST 1`] = `
 Program {
   type: "Program",
   body: Array [
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/4-Babel-Tokens.shot
similarity index 97%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/4-Babel-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/4-Babel-Tokens.shot
index 17ca652dc4a..97d16c68e18 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/4-Babel-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/4-Babel-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-parameters Babel - Tokens 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-param Babel - Tokens 1`] = `
 Array [
   Keyword {
     type: "Keyword",
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/5-AST-Alignment-AST.shot
similarity index 98%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/5-AST-Alignment-AST.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/5-AST-Alignment-AST.shot
index 25dcb54dbeb..f6d5a3c73b3 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/5-AST-Alignment-AST.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/5-AST-Alignment-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-parameters AST Alignment - AST 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-param AST Alignment - AST 1`] = `
 "Snapshot Diff:
 - TSESTree
 + Babel
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/6-AST-Alignment-Tokens.shot
similarity index 76%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/6-AST-Alignment-Tokens.shot
rename to packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/6-AST-Alignment-Tokens.shot
index a99d685df3d..01862c4c751 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters/snapshots/6-AST-Alignment-Tokens.shot
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/snapshots/6-AST-Alignment-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration type-parameters AST Alignment - Token 1`] = `
+exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-param AST Alignment - Token 1`] = `
 "Snapshot Diff:
 Compared values have no visual difference."
 `;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/6-AST-Alignment-Tokens.shot
deleted file mode 100644
index 4e5329e739f..00000000000
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/snapshots/6-AST-Alignment-Tokens.shot
+++ /dev/null
@@ -1,6 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`AST Fixtures declaration ClassDeclaration type-parameters-extends-type-parameters AST Alignment - Token 1`] = `
-"Snapshot Diff:
-Compared values have no visual difference."
-`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/fixture.ts b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/fixture.ts
new file mode 100644
index 00000000000..b790f0b57f6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/fixture.ts
@@ -0,0 +1,3 @@
+class Foo {
+  prop;
+}
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..bdbfa5822bb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,71 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration with-member-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ClassDeclaration {
+      type: "ClassDeclaration",
+      body: ClassBody {
+        type: "ClassBody",
+        body: Array [
+          PropertyDefinition {
+            type: "PropertyDefinition",
+            computed: false,
+            declare: false,
+            key: Identifier {
+              type: "Identifier",
+              name: "prop",
+
+              range: [14, 18],
+              loc: {
+                start: { column: 2, line: 2 },
+                end: { column: 6, line: 2 },
+              },
+            },
+            override: false,
+            static: false,
+            value: null,
+
+            range: [14, 19],
+            loc: {
+              start: { column: 2, line: 2 },
+              end: { column: 7, line: 2 },
+            },
+          },
+        ],
+
+        range: [10, 21],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 1, line: 3 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [6, 9],
+        loc: {
+          start: { column: 6, line: 1 },
+          end: { column: 9, line: 1 },
+        },
+      },
+      superClass: null,
+
+      range: [0, 21],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 1, line: 3 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 22],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 4 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..1184bd1ae08
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration with-member-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "class",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [6, 9],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "prop",
+
+    range: [14, 18],
+    loc: {
+      start: { column: 2, line: 2 },
+      end: { column: 6, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 6, line: 2 },
+      end: { column: 7, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 0, line: 3 },
+      end: { column: 1, line: 3 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..df5b728f558
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,69 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration with-member-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ClassDeclaration {
+      type: "ClassDeclaration",
+      body: ClassBody {
+        type: "ClassBody",
+        body: Array [
+          PropertyDefinition {
+            type: "PropertyDefinition",
+            computed: false,
+            key: Identifier {
+              type: "Identifier",
+              name: "prop",
+
+              range: [14, 18],
+              loc: {
+                start: { column: 2, line: 2 },
+                end: { column: 6, line: 2 },
+              },
+            },
+            static: false,
+            value: null,
+
+            range: [14, 19],
+            loc: {
+              start: { column: 2, line: 2 },
+              end: { column: 7, line: 2 },
+            },
+          },
+        ],
+
+        range: [10, 21],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 1, line: 3 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [6, 9],
+        loc: {
+          start: { column: 6, line: 1 },
+          end: { column: 9, line: 1 },
+        },
+      },
+      superClass: null,
+
+      range: [0, 21],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 1, line: 3 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 22],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 4 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..3fe5916a116
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration with-member-one Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "class",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [6, 9],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "prop",
+
+    range: [14, 18],
+    loc: {
+      start: { column: 2, line: 2 },
+      end: { column: 6, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 6, line: 2 },
+      end: { column: 7, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 0, line: 3 },
+      end: { column: 1, line: 3 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..121e647439e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,75 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration with-member-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      ClassDeclaration {
+        type: 'ClassDeclaration',
+        body: ClassBody {
+          type: 'ClassBody',
+          body: Array [
+            PropertyDefinition {
+              type: 'PropertyDefinition',
+              computed: false,
+-             declare: false,
+              key: Identifier {
+                type: 'Identifier',
+                name: 'prop',
+
+                range: [14, 18],
+                loc: {
+                  start: { column: 2, line: 2 },
+                  end: { column: 6, line: 2 },
+                },
+              },
+-             override: false,
+              static: false,
+              value: null,
+
+              range: [14, 19],
+              loc: {
+                start: { column: 2, line: 2 },
+                end: { column: 7, line: 2 },
+              },
+            },
+          ],
+
+          range: [10, 21],
+          loc: {
+            start: { column: 10, line: 1 },
+            end: { column: 1, line: 3 },
+          },
+        },
+        id: Identifier {
+          type: 'Identifier',
+          name: 'Foo',
+
+          range: [6, 9],
+          loc: {
+            start: { column: 6, line: 1 },
+            end: { column: 9, line: 1 },
+          },
+        },
+        superClass: null,
+
+        range: [0, 21],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 1, line: 3 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 22],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 4 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..89d6bb8a18e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/with-member-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration with-member-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/spec.ts b/packages/ast-spec/src/declaration/ClassDeclaration/spec.ts
index 2154b8863a0..50112b70b5e 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/ClassDeclaration/spec.ts
@@ -1,6 +1,19 @@
 import type { AST_NODE_TYPES } from '../../ast-node-types';
-import type { ClassDeclarationBase } from '../../base/ClassDeclarationBase';
+import type { ClassBase } from '../../base/ClassBase';
+import type { Identifier } from '../../expression/Identifier/spec';
 
-export interface ClassDeclaration extends ClassDeclarationBase {
+interface ClassDeclarationBase extends ClassBase {
   type: AST_NODE_TYPES.ClassDeclaration;
 }
+
+export interface ClassDeclarationWithName extends ClassDeclarationBase {
+  id: Identifier;
+}
+
+export interface ClassDeclarationWithOptionalName extends ClassDeclarationBase {
+  id: Identifier | null;
+}
+
+export type ClassDeclaration =
+  | ClassDeclarationWithName
+  | ClassDeclarationWithOptionalName;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/fixture.ts b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/fixture.ts
new file mode 100644
index 00000000000..0a8ce4f553c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/fixture.ts
@@ -0,0 +1 @@
+export type * as x from 'a';
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..4e1ab2405d4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,48 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ExportAllDeclaration kind-type TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ExportAllDeclaration {
+      type: "ExportAllDeclaration",
+      assertions: Array [],
+      exported: Identifier {
+        type: "Identifier",
+        name: "x",
+
+        range: [17, 18],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      exportKind: "type",
+      source: Literal {
+        type: "Literal",
+        raw: "'a'",
+        value: "a",
+
+        range: [24, 27],
+        loc: {
+          start: { column: 24, line: 1 },
+          end: { column: 27, line: 1 },
+        },
+      },
+
+      range: [0, 28],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 28, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 29],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..a28f9c4f903
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ExportAllDeclaration _error_ kind-type TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..18b68176cbe
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ExportAllDeclaration _error_ kind-type Babel - Error 1`] = `[SyntaxError: Unexpected token (1:12)]`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..f5bfa8f5615
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ExportAllDeclaration kind-type TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "export",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [7, 11],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "*",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "as",
+
+    range: [14, 16],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [19, 23],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'a'",
+
+    range: [24, 27],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 27, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..f9e05e0f6ea
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/kind-type/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ExportAllDeclaration _error_ kind-type Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/fixture.ts b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/fixture.ts
similarity index 100%
rename from packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/fixture.ts
rename to packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/fixture.ts
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..d3c411c7ec3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ExportAllDeclaration _error_ missing-source TSESTree - Error 1`] = `[TSError: Expression expected.]`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..b45b0c8fc85
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ExportAllDeclaration _error_ missing-source Babel - Error 1`] = `[SyntaxError: Unexpected token (1:13)]`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..89889f0ae31
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/missing-source/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ExportAllDeclaration _error_ missing-source Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/snapshots/1-TSESTree-Error.shot
deleted file mode 100644
index acdaf4c735f..00000000000
--- a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/snapshots/1-TSESTree-Error.shot
+++ /dev/null
@@ -1,3 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`AST Fixtures declaration ExportAllDeclaration _error_ no-source TSESTree - Error 1`] = `[TSError: Expression expected.]`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/snapshots/2-Babel-Error.shot
deleted file mode 100644
index 8bd09ace8dc..00000000000
--- a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/snapshots/2-Babel-Error.shot
+++ /dev/null
@@ -1,3 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`AST Fixtures declaration ExportAllDeclaration _error_ no-source Babel - Error 1`] = `[SyntaxError: Unexpected token (1:13)]`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/snapshots/3-Alignment-Error.shot
deleted file mode 100644
index c2ac962baac..00000000000
--- a/packages/ast-spec/src/declaration/ExportAllDeclaration/fixtures/_error_/no-source/snapshots/3-Alignment-Error.shot
+++ /dev/null
@@ -1,3 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`AST Fixtures declaration ExportAllDeclaration _error_ no-source Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ExportAllDeclaration/spec.ts b/packages/ast-spec/src/declaration/ExportAllDeclaration/spec.ts
index 5cf3301a50d..168f7b40b61 100644
--- a/packages/ast-spec/src/declaration/ExportAllDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/ExportAllDeclaration/spec.ts
@@ -7,8 +7,24 @@ import type { ExportKind } from '../ExportAndImportKind';
 
 export interface ExportAllDeclaration extends BaseNode {
   type: AST_NODE_TYPES.ExportAllDeclaration;
-  source: StringLiteral | null;
-  exportKind: ExportKind;
-  exported: Identifier | null;
+  /**
+   * The assertions declared for the export.
+   * ```
+   * export * from 'mod' assert { type: 'json' };
+   * ```
+   */
   assertions: ImportAttribute[];
+  /**
+   * The name for the exported items. `null` if no name is assigned.
+   */
+  exported: Identifier | null;
+  /**
+   * The kind of the export.
+   */
+  // TODO(#1852) - breaking change remove this because it is a semantic error to have it
+  exportKind: ExportKind;
+  /**
+   * The source module being exported from.
+   */
+  source: StringLiteral;
 }
diff --git a/packages/ast-spec/src/declaration/ExportDefaultDeclaration/spec.ts b/packages/ast-spec/src/declaration/ExportDefaultDeclaration/spec.ts
index 2cfe1cce5b3..51b1248854a 100644
--- a/packages/ast-spec/src/declaration/ExportDefaultDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/ExportDefaultDeclaration/spec.ts
@@ -1,15 +1,16 @@
 import type { AST_NODE_TYPES } from '../../ast-node-types';
 import type { BaseNode } from '../../base/BaseNode';
-import type { ExportDeclaration } from '../../unions/ExportDeclaration';
-import type { Expression } from '../../unions/Expression';
+import type { DefaultExportDeclarations } from '../../unions/ExportDeclaration';
 import type { ExportKind } from '../ExportAndImportKind';
 
 export interface ExportDefaultDeclaration extends BaseNode {
   type: AST_NODE_TYPES.ExportDefaultDeclaration;
-  declaration:
-    | // TODO(error handling) - the following are disallowed syntactically, but allowed by TS error recovery:
-    // TSEnumDeclaration, TSModuleDeclaration, TSTypeAliasDeclaration, VariableDeclaration
-    ExportDeclaration
-    | Expression;
+  /**
+   * The declaration being exported.
+   */
+  declaration: DefaultExportDeclarations;
+  /**
+   * The kind of the export.
+   */
   exportKind: ExportKind;
 }
diff --git a/packages/ast-spec/src/declaration/ExportNamedDeclaration/spec.ts b/packages/ast-spec/src/declaration/ExportNamedDeclaration/spec.ts
index 3e2989b7499..061c53f4b46 100644
--- a/packages/ast-spec/src/declaration/ExportNamedDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/ExportNamedDeclaration/spec.ts
@@ -3,15 +3,73 @@ import type { BaseNode } from '../../base/BaseNode';
 import type { StringLiteral } from '../../expression/literal/StringLiteral/spec';
 import type { ExportSpecifier } from '../../special/ExportSpecifier/spec';
 import type { ImportAttribute } from '../../special/ImportAttribute/spec';
-import type { ExportDeclaration } from '../../unions/ExportDeclaration';
+import type { NamedExportDeclarations } from '../../unions/ExportDeclaration';
 import type { ExportKind } from '../ExportAndImportKind';
 
-export interface ExportNamedDeclaration extends BaseNode {
+interface ExportNamedDeclarationBase extends BaseNode {
   type: AST_NODE_TYPES.ExportNamedDeclaration;
-  // TODO(error handling) - ClassExpression is not valid here
-  declaration: ExportDeclaration | null;
-  specifiers: ExportSpecifier[];
-  source: StringLiteral | null;
+  /**
+   * The assertions declared for the export.
+   * ```
+   * export { foo } from 'mod' assert { type: 'json' };
+   * ```
+   * This will be an empty array if `source` is `null`
+   */
+  assertions: ImportAttribute[];
+  /**
+   * The exported declaration.
+   * ```
+   * export const x = 1;
+   * ```
+   * This will be `null` if `source` is not `null`, or if there are `specifiers`
+   */
+  declaration: NamedExportDeclarations | null;
+  /**
+   * The kind of the export.
+   */
   exportKind: ExportKind;
+  /**
+   * The source module being exported from.
+   */
+  source: StringLiteral | null;
+  /**
+   * The specifiers being exported.
+   * ```
+   * export { a, b };
+   * ```
+   * This will be an empty array if `declaration` is not `null`
+   */
+  specifiers: ExportSpecifier[];
+}
+
+export interface ExportNamedDeclarationWithoutSourceWithMultiple
+  extends ExportNamedDeclarationBase {
+  // this will always be empty array
   assertions: ImportAttribute[];
+  declaration: NamedExportDeclarations;
+  source: null;
+  specifiers: ExportSpecifier[];
 }
+
+export interface ExportNamedDeclarationWithoutSourceWithSingle
+  extends ExportNamedDeclarationBase {
+  // this will always be empty array
+  assertions: ImportAttribute[];
+  declaration: null;
+  source: null;
+  // this will always be empty array
+  specifiers: ExportSpecifier[];
+}
+
+export interface ExportNamedDeclarationWithSource
+  extends ExportNamedDeclarationBase {
+  assertions: ImportAttribute[];
+  declaration: null;
+  source: StringLiteral;
+  specifiers: ExportSpecifier[];
+}
+
+export type ExportNamedDeclaration =
+  | ExportNamedDeclarationWithoutSourceWithMultiple
+  | ExportNamedDeclarationWithoutSourceWithSingle
+  | ExportNamedDeclarationWithSource;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/fixture.ts
new file mode 100644
index 00000000000..6c532730c0b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/fixture.ts
@@ -0,0 +1 @@
+function () {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..e8630b3f99c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ missing-id-and-not-exported TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..d0110ccac63
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ missing-id-and-not-exported Babel - Error 1`] = `[SyntaxError: Unexpected token (1:9)]`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..adae3f26337
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-id-and-not-exported/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ missing-id-and-not-exported Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/fixture.ts
new file mode 100644
index 00000000000..0988137a7e7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/fixture.ts
@@ -0,0 +1 @@
+function foo<>() {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..2ffb9878bc9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ missing-type-param TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..83a2a868f15
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ missing-type-param Babel - Error 1`] = `[SyntaxError: Type parameter list cannot be empty. (1:12)]`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..04a70d3af29
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ missing-type-param Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
new file mode 100644
index 00000000000..4e06a77dc7f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
@@ -0,0 +1 @@
+function 1() {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..156bebb725c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ non-identifier-name TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..d23f3eff955
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ non-identifier-name Babel - Error 1`] = `[SyntaxError: Unexpected token (1:9)]`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..f34f77cd1b8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ non-identifier-name Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/fixture.ts
new file mode 100644
index 00000000000..99644e47f36
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/fixture.ts
@@ -0,0 +1 @@
+function foo<1>() {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..8c643863afb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ non-identifier-type-param TSESTree - Error 1`] = `[TSError: Type parameter declaration expected.]`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..8be1b8d27a3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ non-identifier-type-param Babel - Error 1`] = `[SyntaxError: Unexpected token (1:13)]`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..f2b863d8647
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration _error_ non-identifier-type-param Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/fixture.ts
new file mode 100644
index 00000000000..f9df9686dd6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/fixture.ts
@@ -0,0 +1 @@
+async function foo() {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..7a7cd7ea28a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,49 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration async TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: true,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [21, 23],
+        loc: {
+          start: { column: 21, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [15, 18],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..3ca43d1e9fa
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration async TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "async",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [6, 14],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [15, 18],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..c24f3da9207
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/3-Babel-AST.shot
@@ -0,0 +1,49 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration async Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: true,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [21, 23],
+        loc: {
+          start: { column: 21, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [15, 18],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..22c009c000f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration async Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "async",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [6, 14],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [15, 18],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..fe3cf227fba
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration async AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..b7e2ed7bd9a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/async/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration async AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/fixture.ts
new file mode 100644
index 00000000000..b0400ee9b26
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/fixture.ts
@@ -0,0 +1 @@
+function foo() {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..e21b80de90e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,49 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration empty TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [15, 17],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 17, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..d53355506df
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration empty TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..e339b4afda4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/3-Babel-AST.shot
@@ -0,0 +1,49 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration empty Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [15, 17],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 17, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..0b7e51f4235
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration empty Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..b08265806b5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration empty AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..de6b3f7e116
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration empty AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/fixture.ts
new file mode 100644
index 00000000000..f60d20a34b7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/fixture.ts
@@ -0,0 +1 @@
+function* foo() {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..7ad2d7a2dce
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,49 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration generator TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [16, 18],
+        loc: {
+          start: { column: 16, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      expression: false,
+      generator: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [10, 13],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 13, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 18],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 18, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 19],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..d6d22923684
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration generator TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "*",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [10, 13],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..46d3edd3250
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/3-Babel-AST.shot
@@ -0,0 +1,49 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration generator Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [16, 18],
+        loc: {
+          start: { column: 16, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      expression: false,
+      generator: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [10, 13],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 13, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 18],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 18, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 19],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..3fb7fa84513
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration generator Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "*",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [10, 13],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/5-AST-Alignment-AST.shot
similarity index 67%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/5-AST-Alignment-AST.shot
rename to packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/5-AST-Alignment-AST.shot
index 19b8f62ee26..e94e87d038a 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/5-AST-Alignment-AST.shot
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/5-AST-Alignment-AST.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorOne AST Alignment - AST 1`] = `
+exports[`AST Fixtures declaration FunctionDeclaration generator AST Alignment - AST 1`] = `
 "Snapshot Diff:
 Compared values have no visual difference."
 `;
diff --git a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/6-AST-Alignment-Tokens.shot
similarity index 68%
rename from packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/6-AST-Alignment-Tokens.shot
rename to packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/6-AST-Alignment-Tokens.shot
index 915fd1d51f9..033a7496b3c 100644
--- a/packages/ast-spec/src/declaration/ClassDeclaration/fixtures/decoratorOne/snapshots/6-AST-Alignment-Tokens.shot
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/generator/snapshots/6-AST-Alignment-Tokens.shot
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`AST Fixtures declaration ClassDeclaration decoratorOne AST Alignment - Token 1`] = `
+exports[`AST Fixtures declaration FunctionDeclaration generator AST Alignment - Token 1`] = `
 "Snapshot Diff:
 Compared values have no visual difference."
 `;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/fixture.ts
new file mode 100644
index 00000000000..8dca93172ea
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/fixture.ts
@@ -0,0 +1 @@
+function foo(a, b, c) {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..9a6db3d1c4c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,80 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [22, 24],
+        loc: {
+          start: { column: 22, line: 1 },
+          end: { column: 24, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [
+        Identifier {
+          type: "Identifier",
+          name: "a",
+
+          range: [13, 14],
+          loc: {
+            start: { column: 13, line: 1 },
+            end: { column: 14, line: 1 },
+          },
+        },
+        Identifier {
+          type: "Identifier",
+          name: "b",
+
+          range: [16, 17],
+          loc: {
+            start: { column: 16, line: 1 },
+            end: { column: 17, line: 1 },
+          },
+        },
+        Identifier {
+          type: "Identifier",
+          name: "c",
+
+          range: [19, 20],
+          loc: {
+            start: { column: 19, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..08de97f6423
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,116 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-many TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "c",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..c04ed824284
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,80 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [22, 24],
+        loc: {
+          start: { column: 22, line: 1 },
+          end: { column: 24, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [
+        Identifier {
+          type: "Identifier",
+          name: "a",
+
+          range: [13, 14],
+          loc: {
+            start: { column: 13, line: 1 },
+            end: { column: 14, line: 1 },
+          },
+        },
+        Identifier {
+          type: "Identifier",
+          name: "b",
+
+          range: [16, 17],
+          loc: {
+            start: { column: 16, line: 1 },
+            end: { column: 17, line: 1 },
+          },
+        },
+        Identifier {
+          type: "Identifier",
+          name: "c",
+
+          range: [19, 20],
+          loc: {
+            start: { column: 19, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..a0aa4487994
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,116 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-many Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "c",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..f8b80c46b1e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..70640eb186a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/fixture.ts
new file mode 100644
index 00000000000..ef1dd099d3f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/fixture.ts
@@ -0,0 +1 @@
+function foo(a) {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..99d9cdc9e98
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,60 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [16, 18],
+        loc: {
+          start: { column: 16, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [
+        Identifier {
+          type: "Identifier",
+          name: "a",
+
+          range: [13, 14],
+          loc: {
+            start: { column: 13, line: 1 },
+            end: { column: 14, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 18],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 18, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 19],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..81f8b5dc751
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..6e503e760fb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,60 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [16, 18],
+        loc: {
+          start: { column: 16, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [
+        Identifier {
+          type: "Identifier",
+          name: "a",
+
+          range: [13, 14],
+          loc: {
+            start: { column: 13, line: 1 },
+            end: { column: 14, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 18],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 18, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 19],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..802761abb0e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-one Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..5c75a74de72
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..f6f408e32c2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/param-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration param-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/fixture.ts
new file mode 100644
index 00000000000..4fa04cdbc0b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/fixture.ts
@@ -0,0 +1 @@
+function foo(): void {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..d9d3eccf8d7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,67 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration returnType TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [21, 23],
+        loc: {
+          start: { column: 21, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+      returnType: TSTypeAnnotation {
+        type: "TSTypeAnnotation",
+        typeAnnotation: TSVoidKeyword {
+          type: "TSVoidKeyword",
+
+          range: [16, 20],
+          loc: {
+            start: { column: 16, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+
+        range: [14, 20],
+        loc: {
+          start: { column: 14, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..d3930ccf8dc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration returnType TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ":",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "void",
+
+    range: [16, 20],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..8f9c235c429
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/3-Babel-AST.shot
@@ -0,0 +1,67 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration returnType Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [21, 23],
+        loc: {
+          start: { column: 21, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+      returnType: TSTypeAnnotation {
+        type: "TSTypeAnnotation",
+        typeAnnotation: TSVoidKeyword {
+          type: "TSVoidKeyword",
+
+          range: [16, 20],
+          loc: {
+            start: { column: 16, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+
+        range: [14, 20],
+        loc: {
+          start: { column: 14, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..0c94d7108ae
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration returnType Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ":",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "void",
+
+    range: [16, 20],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..d0df21058e9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration returnType AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..0a4b02ae424
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/returnType/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration returnType AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/fixture.ts
new file mode 100644
index 00000000000..36ddc225d14
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/fixture.ts
@@ -0,0 +1 @@
+function foo<T, U, V>() {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..24eae0d3290
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,123 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [24, 26],
+        loc: {
+          start: { column: 24, line: 1 },
+          end: { column: 26, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "T",
+
+              range: [13, 14],
+              loc: {
+                start: { column: 13, line: 1 },
+                end: { column: 14, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [13, 14],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 14, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "U",
+
+              range: [16, 17],
+              loc: {
+                start: { column: 16, line: 1 },
+                end: { column: 17, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [16, 17],
+            loc: {
+              start: { column: 16, line: 1 },
+              end: { column: 17, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "V",
+
+              range: [19, 20],
+              loc: {
+                start: { column: 19, line: 1 },
+                end: { column: 20, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [19, 20],
+            loc: {
+              start: { column: 19, line: 1 },
+              end: { column: 20, line: 1 },
+            },
+          },
+        ],
+
+        range: [12, 21],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 21, line: 1 },
+        },
+      },
+
+      range: [0, 26],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 26, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 27],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..99504b18340
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,136 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-many TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "V",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..690e6d4036b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,90 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [24, 26],
+        loc: {
+          start: { column: 24, line: 1 },
+          end: { column: 26, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "T",
+
+            range: [13, 14],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 14, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "U",
+
+            range: [16, 17],
+            loc: {
+              start: { column: 16, line: 1 },
+              end: { column: 17, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "V",
+
+            range: [19, 20],
+            loc: {
+              start: { column: 19, line: 1 },
+              end: { column: 20, line: 1 },
+            },
+          },
+        ],
+
+        range: [12, 21],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 21, line: 1 },
+        },
+      },
+
+      range: [0, 26],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 26, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 27],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..b7e57a6f404
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,136 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-many Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "V",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..98ace90820f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,130 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      FunctionDeclaration {
+        type: 'FunctionDeclaration',
+        async: false,
+        body: BlockStatement {
+          type: 'BlockStatement',
+          body: Array [],
+
+          range: [24, 26],
+          loc: {
+            start: { column: 24, line: 1 },
+            end: { column: 26, line: 1 },
+          },
+        },
+        expression: false,
+        generator: false,
+        id: Identifier {
+          type: 'Identifier',
+          name: 'foo',
+
+          range: [9, 12],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 12, line: 1 },
+          },
+        },
+        params: Array [],
+        typeParameters: TSTypeParameterDeclaration {
+          type: 'TSTypeParameterDeclaration',
+          params: Array [
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'T',
+-
+-               range: [13, 14],
+-               loc: {
+-                 start: { column: 13, line: 1 },
+-                 end: { column: 14, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'T',
+
+              range: [13, 14],
+              loc: {
+                start: { column: 13, line: 1 },
+                end: { column: 14, line: 1 },
+              },
+            },
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'U',
+-
+-               range: [16, 17],
+-               loc: {
+-                 start: { column: 16, line: 1 },
+-                 end: { column: 17, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'U',
+
+              range: [16, 17],
+              loc: {
+                start: { column: 16, line: 1 },
+                end: { column: 17, line: 1 },
+              },
+            },
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'V',
+-
+-               range: [19, 20],
+-               loc: {
+-                 start: { column: 19, line: 1 },
+-                 end: { column: 20, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'V',
+
+              range: [19, 20],
+              loc: {
+                start: { column: 19, line: 1 },
+                end: { column: 20, line: 1 },
+              },
+            },
+          ],
+
+          range: [12, 21],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 21, line: 1 },
+          },
+        },
+
+        range: [0, 26],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 26, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 27],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..af00d0fb852
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/fixture.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/fixture.ts
new file mode 100644
index 00000000000..7994e752aa8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/fixture.ts
@@ -0,0 +1 @@
+function foo<T>() {}
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..b2caab0f05b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,81 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [18, 20],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "T",
+
+              range: [13, 14],
+              loc: {
+                start: { column: 13, line: 1 },
+                end: { column: 14, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [13, 14],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 14, line: 1 },
+            },
+          },
+        ],
+
+        range: [12, 15],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 15, line: 1 },
+        },
+      },
+
+      range: [0, 20],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 20, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 21],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..9227520d153
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..5083d4d25cb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,70 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    FunctionDeclaration {
+      type: "FunctionDeclaration",
+      async: false,
+      body: BlockStatement {
+        type: "BlockStatement",
+        body: Array [],
+
+        range: [18, 20],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "T",
+
+            range: [13, 14],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 14, line: 1 },
+            },
+          },
+        ],
+
+        range: [12, 15],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 15, line: 1 },
+        },
+      },
+
+      range: [0, 20],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 20, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 21],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..72cd1481fd3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-one Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..b997a40aca3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      FunctionDeclaration {
+        type: 'FunctionDeclaration',
+        async: false,
+        body: BlockStatement {
+          type: 'BlockStatement',
+          body: Array [],
+
+          range: [18, 20],
+          loc: {
+            start: { column: 18, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+        expression: false,
+        generator: false,
+        id: Identifier {
+          type: 'Identifier',
+          name: 'foo',
+
+          range: [9, 12],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 12, line: 1 },
+          },
+        },
+        params: Array [],
+        typeParameters: TSTypeParameterDeclaration {
+          type: 'TSTypeParameterDeclaration',
+          params: Array [
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'T',
+-
+-               range: [13, 14],
+-               loc: {
+-                 start: { column: 13, line: 1 },
+-                 end: { column: 14, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'T',
+
+              range: [13, 14],
+              loc: {
+                start: { column: 13, line: 1 },
+                end: { column: 14, line: 1 },
+              },
+            },
+          ],
+
+          range: [12, 15],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 15, line: 1 },
+          },
+        },
+
+        range: [0, 20],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 21],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..bf84a177ecc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration FunctionDeclaration type-param-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/FunctionDeclaration/spec.ts b/packages/ast-spec/src/declaration/FunctionDeclaration/spec.ts
index 59d7c4ffe39..4fe3d2dc693 100644
--- a/packages/ast-spec/src/declaration/FunctionDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/FunctionDeclaration/spec.ts
@@ -1,8 +1,25 @@
 import type { AST_NODE_TYPES } from '../../ast-node-types';
-import type { FunctionDeclarationBase } from '../../base/FunctionDeclarationBase';
+import type { FunctionBase } from '../../base/FunctionBase';
+import type { Identifier } from '../../expression/Identifier/spec';
 import type { BlockStatement } from '../../statement/BlockStatement/spec';
 
-export interface FunctionDeclaration extends FunctionDeclarationBase {
+interface FunctionDeclarationBase extends FunctionBase {
   type: AST_NODE_TYPES.FunctionDeclaration;
   body: BlockStatement;
+  // TODO(#5020) - make this always `false` if it is not `declare`d instead of `undefined`
+  declare?: false;
+  expression: false;
 }
+
+export interface FunctionDeclarationWithName extends FunctionDeclarationBase {
+  id: Identifier;
+}
+
+export interface FunctionDeclarationWithOptionalName
+  extends FunctionDeclarationBase {
+  id: Identifier | null;
+}
+
+export type FunctionDeclaration =
+  | FunctionDeclarationWithName
+  | FunctionDeclarationWithOptionalName;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/fixture.ts
new file mode 100644
index 00000000000..965d8a69653
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/fixture.ts
@@ -0,0 +1 @@
+import 1 from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..233c225dd50
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ default-non-identifier TSESTree - Error 1`] = `[TSError: Declaration or statement expected.]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..438c9cdf750
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ default-non-identifier Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:7)]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..2e0bcbec5a5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/default-non-identifier/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ default-non-identifier Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/fixture.ts
new file mode 100644
index 00000000000..f3cb6e658e2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/fixture.ts
@@ -0,0 +1 @@
+import { b }, * as a from 'a';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..d94d399517f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ named-and-namespace TSESTree - Error 1`] = `[TSError: 'from' expected.]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..9cf4c4b719a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ named-and-namespace Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "from" (1:12)]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..89fae3fa27c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-and-namespace/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ named-and-namespace Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/fixture.ts
new file mode 100644
index 00000000000..6a7fb92600d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/fixture.ts
@@ -0,0 +1 @@
+import { 1 } from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..2ca1651099b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ named-non-identifier TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..970528e3253
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ named-non-identifier Babel - Error 1`] = `[SyntaxError: Unexpected token (1:9)]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..fefbeef9c52
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/named-non-identifier/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ named-non-identifier Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/fixture.ts
new file mode 100644
index 00000000000..9f7ee22b7dd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/fixture.ts
@@ -0,0 +1 @@
+import * as b, a from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..9d2be22fe16
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-and-default TSESTree - Error 1`] = `[TSError: 'from' expected.]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..294d069aacc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-and-default Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "from" (1:13)]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..6e491db0e63
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-default/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-and-default Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/fixture.ts
new file mode 100644
index 00000000000..52bcac2fdbf
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/fixture.ts
@@ -0,0 +1 @@
+import * as a, { b } from 'a';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..a2271606e4b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-and-named TSESTree - Error 1`] = `[TSError: 'from' expected.]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..605940a8433
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-and-named Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "from" (1:13)]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..f1e891dbeca
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-named/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-and-named Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/fixture.ts
new file mode 100644
index 00000000000..6d678fc5983
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/fixture.ts
@@ -0,0 +1 @@
+import * as a, * as b from 'a';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..0a5d4ab3922
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-and-namespace TSESTree - Error 1`] = `[TSError: 'from' expected.]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..8efbfcaf519
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-and-namespace Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "from" (1:13)]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..e3c8c7a6288
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-and-namespace/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-and-namespace Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/fixture.ts
new file mode 100644
index 00000000000..539e09df8d0
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/fixture.ts
@@ -0,0 +1 @@
+import * as 1 from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..fa9ec459a92
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-non-identifier TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..a511cc6c94d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-non-identifier Babel - Error 1`] = `[SyntaxError: Unexpected token (1:12)]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..f0d97ae32bc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/namespace-non-identifier/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ namespace-non-identifier Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/fixture.ts
new file mode 100644
index 00000000000..a4a63604c81
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/fixture.ts
@@ -0,0 +1 @@
+import * as x from module;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..4cfff84fd98
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ non-string-source TSESTree - Error 1`] = `[TSError: Module specifier must be a string literal.]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..49abb836662
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ non-string-source Babel - Error 1`] = `[SyntaxError: Unexpected token (1:19)]`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..0d5964ffc24
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/_error_/non-string-source/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration _error_ non-string-source Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/fixture.ts
new file mode 100644
index 00000000000..3bd366a8d05
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/fixture.ts
@@ -0,0 +1 @@
+import * as a from 'mod' assert { type: 'json' };
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..877884e2c9a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,90 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration assertion TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [
+        ImportAttribute {
+          type: "ImportAttribute",
+          key: Identifier {
+            type: "Identifier",
+            name: "type",
+
+            range: [34, 38],
+            loc: {
+              start: { column: 34, line: 1 },
+              end: { column: 38, line: 1 },
+            },
+          },
+          value: Literal {
+            type: "Literal",
+            raw: "'json'",
+            value: "json",
+
+            range: [40, 46],
+            loc: {
+              start: { column: 40, line: 1 },
+              end: { column: 46, line: 1 },
+            },
+          },
+
+          range: [34, 46],
+          loc: {
+            start: { column: 34, line: 1 },
+            end: { column: 46, line: 1 },
+          },
+        },
+      ],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [19, 24],
+        loc: {
+          start: { column: 19, line: 1 },
+          end: { column: 24, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportNamespaceSpecifier {
+          type: "ImportNamespaceSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+
+          range: [7, 13],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 49],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 49, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 50],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..3b0706c7d31
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,136 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration assertion TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "*",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "as",
+
+    range: [9, 11],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [14, 18],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [19, 24],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "assert",
+
+    range: [25, 31],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 31, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [32, 33],
+    loc: {
+      start: { column: 32, line: 1 },
+      end: { column: 33, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [34, 38],
+    loc: {
+      start: { column: 34, line: 1 },
+      end: { column: 38, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ":",
+
+    range: [38, 39],
+    loc: {
+      start: { column: 38, line: 1 },
+      end: { column: 39, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'json'",
+
+    range: [40, 46],
+    loc: {
+      start: { column: 40, line: 1 },
+      end: { column: 46, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [47, 48],
+    loc: {
+      start: { column: 47, line: 1 },
+      end: { column: 48, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [48, 49],
+    loc: {
+      start: { column: 48, line: 1 },
+      end: { column: 49, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..54c2381228b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/3-Babel-AST.shot
@@ -0,0 +1,90 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration assertion Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [
+        ImportAttribute {
+          type: "ImportAttribute",
+          key: Identifier {
+            type: "Identifier",
+            name: "type",
+
+            range: [34, 38],
+            loc: {
+              start: { column: 34, line: 1 },
+              end: { column: 38, line: 1 },
+            },
+          },
+          value: Literal {
+            type: "Literal",
+            raw: "'json'",
+            value: "json",
+
+            range: [40, 46],
+            loc: {
+              start: { column: 40, line: 1 },
+              end: { column: 46, line: 1 },
+            },
+          },
+
+          range: [34, 46],
+          loc: {
+            start: { column: 34, line: 1 },
+            end: { column: 46, line: 1 },
+          },
+        },
+      ],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [19, 24],
+        loc: {
+          start: { column: 19, line: 1 },
+          end: { column: 24, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportNamespaceSpecifier {
+          type: "ImportNamespaceSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+
+          range: [7, 13],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 49],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 49, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 50],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..30c2bd49245
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,136 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration assertion Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "*",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "as",
+
+    range: [9, 11],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [14, 18],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [19, 24],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "assert",
+
+    range: [25, 31],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 31, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [32, 33],
+    loc: {
+      start: { column: 32, line: 1 },
+      end: { column: 33, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [34, 38],
+    loc: {
+      start: { column: 34, line: 1 },
+      end: { column: 38, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ":",
+
+    range: [38, 39],
+    loc: {
+      start: { column: 38, line: 1 },
+      end: { column: 39, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'json'",
+
+    range: [40, 46],
+    loc: {
+      start: { column: 40, line: 1 },
+      end: { column: 46, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [47, 48],
+    loc: {
+      start: { column: 47, line: 1 },
+      end: { column: 48, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [48, 49],
+    loc: {
+      start: { column: 48, line: 1 },
+      end: { column: 49, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..c7b85e439da
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration assertion AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..3189b2704ef
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/assertion/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration assertion AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/fixture.ts
new file mode 100644
index 00000000000..ac5f18056a3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/fixture.ts
@@ -0,0 +1 @@
+import a, { b, c, d } from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..3b5e6f5d956
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,149 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [27, 32],
+        loc: {
+          start: { column: 27, line: 1 },
+          end: { column: 32, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "c",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "c",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+
+          range: [15, 16],
+          loc: {
+            start: { column: 15, line: 1 },
+            end: { column: 16, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "d",
+
+            range: [18, 19],
+            loc: {
+              start: { column: 18, line: 1 },
+              end: { column: 19, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "d",
+
+            range: [18, 19],
+            loc: {
+              start: { column: 18, line: 1 },
+              end: { column: 19, line: 1 },
+            },
+          },
+
+          range: [18, 19],
+          loc: {
+            start: { column: 18, line: 1 },
+            end: { column: 19, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 33],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 33, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 34],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..1d4c57f89eb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,136 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-many TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "c",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "d",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [22, 26],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [27, 32],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 32, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [32, 33],
+    loc: {
+      start: { column: 32, line: 1 },
+      end: { column: 33, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..d1207f8c6cc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,149 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [27, 32],
+        loc: {
+          start: { column: 27, line: 1 },
+          end: { column: 32, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "c",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "c",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+
+          range: [15, 16],
+          loc: {
+            start: { column: 15, line: 1 },
+            end: { column: 16, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "d",
+
+            range: [18, 19],
+            loc: {
+              start: { column: 18, line: 1 },
+              end: { column: 19, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "d",
+
+            range: [18, 19],
+            loc: {
+              start: { column: 18, line: 1 },
+              end: { column: 19, line: 1 },
+            },
+          },
+
+          range: [18, 19],
+          loc: {
+            start: { column: 18, line: 1 },
+            end: { column: 19, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 33],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 33, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 34],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..3cfb21679c8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,136 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-many Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "c",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "d",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [22, 26],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [27, 32],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 32, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [32, 33],
+    loc: {
+      start: { column: 32, line: 1 },
+      end: { column: 33, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..5a7d0eb9f83
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..00895e19374
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/fixture.ts
new file mode 100644
index 00000000000..d808a750ce8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/fixture.ts
@@ -0,0 +1,2 @@
+// prettier-ignore
+import a, {} from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..0e94a0b6bb9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,59 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-none TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [37, 42],
+        loc: {
+          start: { column: 18, line: 2 },
+          end: { column: 23, line: 2 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [26, 27],
+            loc: {
+              start: { column: 7, line: 2 },
+              end: { column: 8, line: 2 },
+            },
+          },
+
+          range: [26, 27],
+          loc: {
+            start: { column: 7, line: 2 },
+            end: { column: 8, line: 2 },
+          },
+        },
+      ],
+
+      range: [19, 43],
+      loc: {
+        start: { column: 0, line: 2 },
+        end: { column: 24, line: 2 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [19, 44],
+  loc: {
+    start: { column: 0, line: 2 },
+    end: { column: 0, line: 3 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..99bb6d113e5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-none TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [19, 25],
+    loc: {
+      start: { column: 0, line: 2 },
+      end: { column: 6, line: 2 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [26, 27],
+    loc: {
+      start: { column: 7, line: 2 },
+      end: { column: 8, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 8, line: 2 },
+      end: { column: 9, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 10, line: 2 },
+      end: { column: 11, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [30, 31],
+    loc: {
+      start: { column: 11, line: 2 },
+      end: { column: 12, line: 2 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [32, 36],
+    loc: {
+      start: { column: 13, line: 2 },
+      end: { column: 17, line: 2 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [37, 42],
+    loc: {
+      start: { column: 18, line: 2 },
+      end: { column: 23, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [42, 43],
+    loc: {
+      start: { column: 23, line: 2 },
+      end: { column: 24, line: 2 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..ee34379e43e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/3-Babel-AST.shot
@@ -0,0 +1,59 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-none Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [37, 42],
+        loc: {
+          start: { column: 18, line: 2 },
+          end: { column: 23, line: 2 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [26, 27],
+            loc: {
+              start: { column: 7, line: 2 },
+              end: { column: 8, line: 2 },
+            },
+          },
+
+          range: [26, 27],
+          loc: {
+            start: { column: 7, line: 2 },
+            end: { column: 8, line: 2 },
+          },
+        },
+      ],
+
+      range: [19, 43],
+      loc: {
+        start: { column: 0, line: 2 },
+        end: { column: 24, line: 2 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [19, 44],
+  loc: {
+    start: { column: 0, line: 2 },
+    end: { column: 0, line: 3 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..56ab10c4f1c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-none Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [19, 25],
+    loc: {
+      start: { column: 0, line: 2 },
+      end: { column: 6, line: 2 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [26, 27],
+    loc: {
+      start: { column: 7, line: 2 },
+      end: { column: 8, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 8, line: 2 },
+      end: { column: 9, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 10, line: 2 },
+      end: { column: 11, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [30, 31],
+    loc: {
+      start: { column: 11, line: 2 },
+      end: { column: 12, line: 2 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [32, 36],
+    loc: {
+      start: { column: 13, line: 2 },
+      end: { column: 17, line: 2 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [37, 42],
+    loc: {
+      start: { column: 18, line: 2 },
+      end: { column: 23, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [42, 43],
+    loc: {
+      start: { column: 23, line: 2 },
+      end: { column: 24, line: 2 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..77b9d9ec72b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-none AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..db5dec353c2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-none/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-none AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/fixture.ts
new file mode 100644
index 00000000000..5e938031ed6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/fixture.ts
@@ -0,0 +1 @@
+import a, { b } from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..362d429e027
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,89 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [21, 26],
+        loc: {
+          start: { column: 21, line: 1 },
+          end: { column: 26, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 27],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 27, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 28],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..99806f28e2f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [16, 20],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [21, 26],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [26, 27],
+    loc: {
+      start: { column: 26, line: 1 },
+      end: { column: 27, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..45b6d3ec61e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,89 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [21, 26],
+        loc: {
+          start: { column: 21, line: 1 },
+          end: { column: 26, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 27],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 27, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 28],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..e11fa0be693
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-one Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [16, 20],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [21, 26],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [26, 27],
+    loc: {
+      start: { column: 26, line: 1 },
+      end: { column: 27, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..8661b6d43b2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..8f0c817495a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-named-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-named-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/fixture.ts
new file mode 100644
index 00000000000..e18354616a7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/fixture.ts
@@ -0,0 +1 @@
+import a, * as b from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..88c4eac8c15
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,78 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-namespace TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [22, 27],
+        loc: {
+          start: { column: 22, line: 1 },
+          end: { column: 27, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+        ImportNamespaceSpecifier {
+          type: "ImportNamespaceSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+
+          range: [10, 16],
+          loc: {
+            start: { column: 10, line: 1 },
+            end: { column: 16, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 28],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 28, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 29],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..f78a2e96178
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-namespace TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "*",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "as",
+
+    range: [12, 14],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [17, 21],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [22, 27],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 27, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..25d8c6db0a3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/3-Babel-AST.shot
@@ -0,0 +1,78 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-namespace Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [22, 27],
+        loc: {
+          start: { column: 22, line: 1 },
+          end: { column: 27, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+        ImportNamespaceSpecifier {
+          type: "ImportNamespaceSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+
+          range: [10, 16],
+          loc: {
+            start: { column: 10, line: 1 },
+            end: { column: 16, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 28],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 28, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 29],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..b6bc0f06e1d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-namespace Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "*",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "as",
+
+    range: [12, 14],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [17, 21],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [22, 27],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 27, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..c975ae69118
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-namespace AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..2ea3772b5fc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default-and-namespace/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default-and-namespace AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/fixture.ts
new file mode 100644
index 00000000000..b4fa44ea435
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/fixture.ts
@@ -0,0 +1 @@
+import a from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..8575ecc99e2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,59 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [14, 19],
+        loc: {
+          start: { column: 14, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 20],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 20, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 21],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..b2ac2cf753d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [9, 13],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [14, 19],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..bfb44b15fa6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/3-Babel-AST.shot
@@ -0,0 +1,59 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [14, 19],
+        loc: {
+          start: { column: 14, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportDefaultSpecifier {
+          type: "ImportDefaultSpecifier",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 20],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 20, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 21],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..e5c09dd423e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [9, 13],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [14, 19],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..2524045a807
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..75669766d63
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/default/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration default AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/fixture.ts
new file mode 100644
index 00000000000..4c8852af562
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/fixture.ts
@@ -0,0 +1 @@
+import { a, b, c } from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..a90f8ca955a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,130 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [24, 29],
+        loc: {
+          start: { column: 24, line: 1 },
+          end: { column: 29, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [9, 10],
+            loc: {
+              start: { column: 9, line: 1 },
+              end: { column: 10, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [9, 10],
+            loc: {
+              start: { column: 9, line: 1 },
+              end: { column: 10, line: 1 },
+            },
+          },
+
+          range: [9, 10],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 10, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "c",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "c",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+
+          range: [15, 16],
+          loc: {
+            start: { column: 15, line: 1 },
+            end: { column: 16, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 30],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 30, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 31],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..8eba9974a71
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,116 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-many TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "c",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [19, 23],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [24, 29],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 29, line: 1 },
+      end: { column: 30, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..89d89d705a6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,130 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [24, 29],
+        loc: {
+          start: { column: 24, line: 1 },
+          end: { column: 29, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [9, 10],
+            loc: {
+              start: { column: 9, line: 1 },
+              end: { column: 10, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [9, 10],
+            loc: {
+              start: { column: 9, line: 1 },
+              end: { column: 10, line: 1 },
+            },
+          },
+
+          range: [9, 10],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 10, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "b",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "c",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "c",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+
+          range: [15, 16],
+          loc: {
+            start: { column: 15, line: 1 },
+            end: { column: 16, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 30],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 30, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 31],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..123471f1513
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,116 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-many Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "c",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [19, 23],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [24, 29],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 29, line: 1 },
+      end: { column: 30, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..3f4b4b678e7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..254949c9452
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/fixture.ts
new file mode 100644
index 00000000000..421d8a81af3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/fixture.ts
@@ -0,0 +1 @@
+import {} from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..12f54a5140e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,39 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-none TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [15, 20],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      specifiers: Array [],
+
+      range: [0, 21],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 21, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 22],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..04c72987e07
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-none TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [10, 14],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [15, 20],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..cf425c46b79
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/3-Babel-AST.shot
@@ -0,0 +1,39 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-none Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [15, 20],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      specifiers: Array [],
+
+      range: [0, 21],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 21, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 22],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..ec45fb03592
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-none Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [10, 14],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [15, 20],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..aa52a0d98d1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-none AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..4f0ab4858e6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-none/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-none AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/fixture.ts
new file mode 100644
index 00000000000..7f1f6a4aa22
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/fixture.ts
@@ -0,0 +1 @@
+import { a } from 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..9030519529e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,70 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [18, 23],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [9, 10],
+            loc: {
+              start: { column: 9, line: 1 },
+              end: { column: 10, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [9, 10],
+            loc: {
+              start: { column: 9, line: 1 },
+              end: { column: 10, line: 1 },
+            },
+          },
+
+          range: [9, 10],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 10, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..b437ec118b9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [13, 17],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [18, 23],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..6bc6fe7a38b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,70 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [18, 23],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+      specifiers: Array [
+        ImportSpecifier {
+          type: "ImportSpecifier",
+          imported: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [9, 10],
+            loc: {
+              start: { column: 9, line: 1 },
+              end: { column: 10, line: 1 },
+            },
+          },
+          importKind: "value",
+          local: Identifier {
+            type: "Identifier",
+            name: "a",
+
+            range: [9, 10],
+            loc: {
+              start: { column: 9, line: 1 },
+              end: { column: 10, line: 1 },
+            },
+          },
+
+          range: [9, 10],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 10, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..fddf4bb21ef
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-one Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "from",
+
+    range: [13, 17],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [18, 23],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..a502907e8f6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..f1aacd2d411
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/named-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration named-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/fixture.ts b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/fixture.ts
new file mode 100644
index 00000000000..381cd70b72f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/fixture.ts
@@ -0,0 +1 @@
+import 'mod';
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..62da72509bd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,39 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration side-effect TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [7, 12],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      specifiers: Array [],
+
+      range: [0, 13],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 14],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..dd471c34db4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,36 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration side-effect TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [7, 12],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..ab134ebecf8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/3-Babel-AST.shot
@@ -0,0 +1,39 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration side-effect Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ImportDeclaration {
+      type: "ImportDeclaration",
+      assertions: Array [],
+      importKind: "value",
+      source: Literal {
+        type: "Literal",
+        raw: "'mod'",
+        value: "mod",
+
+        range: [7, 12],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      specifiers: Array [],
+
+      range: [0, 13],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 14],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..d8e354e5b03
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,36 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration side-effect Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [7, 12],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..2fa96b2dc1c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration side-effect AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..1d074a39903
--- /dev/null
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/fixtures/side-effect/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ImportDeclaration side-effect AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/ImportDeclaration/spec.ts b/packages/ast-spec/src/declaration/ImportDeclaration/spec.ts
index b9689fe2c09..389af77f87a 100644
--- a/packages/ast-spec/src/declaration/ImportDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/ImportDeclaration/spec.ts
@@ -7,8 +7,31 @@ import type { ImportKind } from '../ExportAndImportKind';
 
 export interface ImportDeclaration extends BaseNode {
   type: AST_NODE_TYPES.ImportDeclaration;
+  /**
+   * The assertions declared for the export.
+   * ```
+   * import * from 'mod' assert { type: 'json' };
+   * ```
+   */
+  assertions: ImportAttribute[];
+  /**
+   * The kind of the import.
+   */
+  importKind: ImportKind;
+  /**
+   * The source module being imported from.
+   */
   source: StringLiteral;
+  /**
+   * The specifiers being imported.
+   * If this is an empty array then either there are no specifiers:
+   * ```
+   * import {} from 'mod';
+   * ```
+   * Or it is a side-effect import:
+   * ```
+   * import 'mod';
+   * ```
+   */
   specifiers: ImportClause[];
-  importKind: ImportKind;
-  assertions: ImportAttribute[];
 }
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/fixture.ts
new file mode 100644
index 00000000000..204adf1135a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/fixture.ts
@@ -0,0 +1 @@
+declare async function foo();
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..d01382249a1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,40 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction async TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: true,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [23, 26],
+        loc: {
+          start: { column: 23, line: 1 },
+          end: { column: 26, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 29],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 29, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 30],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..79f1c74928b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ async TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..01db37879fb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ async Babel - Error 1`] = `[SyntaxError: Missing semicolon. (1:7)]`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..57b56f38b08
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction async TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "async",
+
+    range: [8, 13],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [14, 22],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [23, 26],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [26, 27],
+    loc: {
+      start: { column: 26, line: 1 },
+      end: { column: 27, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [28, 29],
+    loc: {
+      start: { column: 28, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..1f36cb0955f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/async/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ async Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/fixture.ts
new file mode 100644
index 00000000000..d99be022e46
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/fixture.ts
@@ -0,0 +1 @@
+declare function foo(): void {};
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..ca0dba2a0c3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ declare-with-body TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..e56bbb59892
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ declare-with-body Babel - Error 1`] = `[SyntaxError: An implementation cannot be declared in ambient contexts. (1:0)]`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..22b125b5643
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ declare-with-body Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/fixture.ts
new file mode 100644
index 00000000000..9b557f21605
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/fixture.ts
@@ -0,0 +1 @@
+declare function ();
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..53a142d37be
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ missing-id-and-not-exported TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..bb9716addfb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ missing-id-and-not-exported Babel - Error 1`] = `[SyntaxError: Unexpected token (1:17)]`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..7bd554c552a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-id-and-not-exported/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ missing-id-and-not-exported Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/fixture.ts
new file mode 100644
index 00000000000..a209e2670b2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/fixture.ts
@@ -0,0 +1 @@
+declare function foo<>(): void;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..217a78df58b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ missing-type-param TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..be819649c55
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ missing-type-param Babel - Error 1`] = `[SyntaxError: Type parameter list cannot be empty. (1:20)]`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..83fabb4dfc7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ missing-type-param Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/fixture.ts
new file mode 100644
index 00000000000..15adf45390c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/fixture.ts
@@ -0,0 +1 @@
+declare function 1();
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..86f0f5e5e10
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ non-identifier-name TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..12fadb8985a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ non-identifier-name Babel - Error 1`] = `[SyntaxError: Unexpected token (1:17)]`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..0587657ad4e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ non-identifier-name Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/fixture.ts
new file mode 100644
index 00000000000..0143e128d1f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/fixture.ts
@@ -0,0 +1 @@
+declare function f<1>(): void;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..4b033027f13
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ non-identifier-type-param TSESTree - Error 1`] = `[TSError: Type parameter declaration expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..82c36588558
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ non-identifier-type-param Babel - Error 1`] = `[SyntaxError: Unexpected token (1:19)]`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..0d57d7e26a4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction _error_ non-identifier-type-param Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/fixture.ts
new file mode 100644
index 00000000000..a55ca703c8e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/fixture.ts
@@ -0,0 +1 @@
+declare function foo();
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..59ea1f2fa4c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,40 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction empty TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..68ee13556c4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction empty TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..43be5f098ab
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/3-Babel-AST.shot
@@ -0,0 +1,40 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction empty Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..ec3fc4b9093
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction empty Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..89f8ab5e347
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction empty AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..e5a96e857c6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction empty AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/fixture.ts
new file mode 100644
index 00000000000..55243eab2f5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/fixture.ts
@@ -0,0 +1 @@
+declare function* foo();
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..ed8b5305792
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,40 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction generator TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [18, 21],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 21, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..a0152865940
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction generator TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "*",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [18, 21],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..3da973bf9f5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/3-Babel-AST.shot
@@ -0,0 +1,40 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction generator Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [18, 21],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 21, line: 1 },
+        },
+      },
+      params: Array [],
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..58082427903
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction generator Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "*",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [18, 21],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..e5478271a49
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction generator AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..0c5870a8a61
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/generator/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction generator AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/fixture.ts
new file mode 100644
index 00000000000..3f5ccd7a7bf
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/fixture.ts
@@ -0,0 +1 @@
+declare function foo(a, b, c);
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..a7f8479f43a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,71 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [
+        Identifier {
+          type: "Identifier",
+          name: "a",
+
+          range: [21, 22],
+          loc: {
+            start: { column: 21, line: 1 },
+            end: { column: 22, line: 1 },
+          },
+        },
+        Identifier {
+          type: "Identifier",
+          name: "b",
+
+          range: [24, 25],
+          loc: {
+            start: { column: 24, line: 1 },
+            end: { column: 25, line: 1 },
+          },
+        },
+        Identifier {
+          type: "Identifier",
+          name: "c",
+
+          range: [27, 28],
+          loc: {
+            start: { column: 27, line: 1 },
+            end: { column: 28, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 30],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 30, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 31],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..f6aa7066f1a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,116 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-many TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "c",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [28, 29],
+    loc: {
+      start: { column: 28, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 29, line: 1 },
+      end: { column: 30, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..d1e098a0e89
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,71 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [
+        Identifier {
+          type: "Identifier",
+          name: "a",
+
+          range: [21, 22],
+          loc: {
+            start: { column: 21, line: 1 },
+            end: { column: 22, line: 1 },
+          },
+        },
+        Identifier {
+          type: "Identifier",
+          name: "b",
+
+          range: [24, 25],
+          loc: {
+            start: { column: 24, line: 1 },
+            end: { column: 25, line: 1 },
+          },
+        },
+        Identifier {
+          type: "Identifier",
+          name: "c",
+
+          range: [27, 28],
+          loc: {
+            start: { column: 27, line: 1 },
+            end: { column: 28, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 30],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 30, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 31],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..c27b9fa0a5e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,116 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-many Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "b",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "c",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [28, 29],
+    loc: {
+      start: { column: 28, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 29, line: 1 },
+      end: { column: 30, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..cfed52f085e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..d41363d11c2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/fixture.ts
new file mode 100644
index 00000000000..1e929f63edd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/fixture.ts
@@ -0,0 +1 @@
+declare function foo(a);
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..1f21a6f71f8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,51 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [
+        Identifier {
+          type: "Identifier",
+          name: "a",
+
+          range: [21, 22],
+          loc: {
+            start: { column: 21, line: 1 },
+            end: { column: 22, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..d8412c94212
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-one TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..abf7337612c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,51 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [
+        Identifier {
+          type: "Identifier",
+          name: "a",
+
+          range: [21, 22],
+          loc: {
+            start: { column: 21, line: 1 },
+            end: { column: 22, line: 1 },
+          },
+        },
+      ],
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..9dba1e7717c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-one Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..81f8c45d656
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..ab3a33eb7f9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/param-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction param-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/fixture.ts
new file mode 100644
index 00000000000..7ab5bf14937
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/fixture.ts
@@ -0,0 +1 @@
+declare function foo(): void;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..45e65dbe80a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction returnType TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [],
+      returnType: TSTypeAnnotation {
+        type: "TSTypeAnnotation",
+        typeAnnotation: TSVoidKeyword {
+          type: "TSVoidKeyword",
+
+          range: [24, 28],
+          loc: {
+            start: { column: 24, line: 1 },
+            end: { column: 28, line: 1 },
+          },
+        },
+
+        range: [22, 28],
+        loc: {
+          start: { column: 22, line: 1 },
+          end: { column: 28, line: 1 },
+        },
+      },
+
+      range: [0, 29],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 29, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 30],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..f06fda6f01e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction returnType TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ":",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "void",
+
+    range: [24, 28],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [28, 29],
+    loc: {
+      start: { column: 28, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..1ccc35aaadb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/3-Babel-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction returnType Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [],
+      returnType: TSTypeAnnotation {
+        type: "TSTypeAnnotation",
+        typeAnnotation: TSVoidKeyword {
+          type: "TSVoidKeyword",
+
+          range: [24, 28],
+          loc: {
+            start: { column: 24, line: 1 },
+            end: { column: 28, line: 1 },
+          },
+        },
+
+        range: [22, 28],
+        loc: {
+          start: { column: 22, line: 1 },
+          end: { column: 28, line: 1 },
+        },
+      },
+
+      range: [0, 29],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 29, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 30],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..703e02000f5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction returnType Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ":",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "void",
+
+    range: [24, 28],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [28, 29],
+    loc: {
+      start: { column: 28, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..bddda38b36f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction returnType AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..994903ee609
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/returnType/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction returnType AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/fixture.ts
new file mode 100644
index 00000000000..4ab67258323
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/fixture.ts
@@ -0,0 +1 @@
+declare function foo<T, U, V>();
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..aefd6e905e2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,114 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [],
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "T",
+
+              range: [21, 22],
+              loc: {
+                start: { column: 21, line: 1 },
+                end: { column: 22, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [21, 22],
+            loc: {
+              start: { column: 21, line: 1 },
+              end: { column: 22, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "U",
+
+              range: [24, 25],
+              loc: {
+                start: { column: 24, line: 1 },
+                end: { column: 25, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [24, 25],
+            loc: {
+              start: { column: 24, line: 1 },
+              end: { column: 25, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "V",
+
+              range: [27, 28],
+              loc: {
+                start: { column: 27, line: 1 },
+                end: { column: 28, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [27, 28],
+            loc: {
+              start: { column: 27, line: 1 },
+              end: { column: 28, line: 1 },
+            },
+          },
+        ],
+
+        range: [20, 29],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 29, line: 1 },
+        },
+      },
+
+      range: [0, 32],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 32, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 33],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..92b21a76dcf
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,136 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-many TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "V",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [28, 29],
+    loc: {
+      start: { column: 28, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 29, line: 1 },
+      end: { column: 30, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [30, 31],
+    loc: {
+      start: { column: 30, line: 1 },
+      end: { column: 31, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [31, 32],
+    loc: {
+      start: { column: 31, line: 1 },
+      end: { column: 32, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..76dc2ebf1f5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,81 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [],
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "T",
+
+            range: [21, 22],
+            loc: {
+              start: { column: 21, line: 1 },
+              end: { column: 22, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "U",
+
+            range: [24, 25],
+            loc: {
+              start: { column: 24, line: 1 },
+              end: { column: 25, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "V",
+
+            range: [27, 28],
+            loc: {
+              start: { column: 27, line: 1 },
+              end: { column: 28, line: 1 },
+            },
+          },
+        ],
+
+        range: [20, 29],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 29, line: 1 },
+        },
+      },
+
+      range: [0, 32],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 32, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 33],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..6aaaa58051c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,136 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-many Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "V",
+
+    range: [27, 28],
+    loc: {
+      start: { column: 27, line: 1 },
+      end: { column: 28, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [28, 29],
+    loc: {
+      start: { column: 28, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 29, line: 1 },
+      end: { column: 30, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [30, 31],
+    loc: {
+      start: { column: 30, line: 1 },
+      end: { column: 31, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [31, 32],
+    loc: {
+      start: { column: 31, line: 1 },
+      end: { column: 32, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..5c07aedab59
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,121 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      TSDeclareFunction {
+        type: 'TSDeclareFunction',
+        async: false,
+        declare: true,
+        expression: false,
+        generator: false,
+        id: Identifier {
+          type: 'Identifier',
+          name: 'foo',
+
+          range: [17, 20],
+          loc: {
+            start: { column: 17, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+        params: Array [],
+        typeParameters: TSTypeParameterDeclaration {
+          type: 'TSTypeParameterDeclaration',
+          params: Array [
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'T',
+-
+-               range: [21, 22],
+-               loc: {
+-                 start: { column: 21, line: 1 },
+-                 end: { column: 22, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'T',
+
+              range: [21, 22],
+              loc: {
+                start: { column: 21, line: 1 },
+                end: { column: 22, line: 1 },
+              },
+            },
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'U',
+-
+-               range: [24, 25],
+-               loc: {
+-                 start: { column: 24, line: 1 },
+-                 end: { column: 25, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'U',
+
+              range: [24, 25],
+              loc: {
+                start: { column: 24, line: 1 },
+                end: { column: 25, line: 1 },
+              },
+            },
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'V',
+-
+-               range: [27, 28],
+-               loc: {
+-                 start: { column: 27, line: 1 },
+-                 end: { column: 28, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'V',
+
+              range: [27, 28],
+              loc: {
+                start: { column: 27, line: 1 },
+                end: { column: 28, line: 1 },
+              },
+            },
+          ],
+
+          range: [20, 29],
+          loc: {
+            start: { column: 20, line: 1 },
+            end: { column: 29, line: 1 },
+          },
+        },
+
+        range: [0, 32],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 32, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 33],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..cae8ddcdbee
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/fixture.ts
new file mode 100644
index 00000000000..3f66cd9c460
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/fixture.ts
@@ -0,0 +1 @@
+declare function foo<T>();
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..4767a93811c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,72 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [],
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "T",
+
+              range: [21, 22],
+              loc: {
+                start: { column: 21, line: 1 },
+                end: { column: 22, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [21, 22],
+            loc: {
+              start: { column: 21, line: 1 },
+              end: { column: 22, line: 1 },
+            },
+          },
+        ],
+
+        range: [20, 23],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+
+      range: [0, 26],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 26, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 27],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..cf3ce53768e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-one TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..745e9cba393
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,61 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      declare: true,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [17, 20],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+      params: Array [],
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "T",
+
+            range: [21, 22],
+            loc: {
+              start: { column: 21, line: 1 },
+              end: { column: 22, line: 1 },
+            },
+          },
+        ],
+
+        range: [20, 23],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+
+      range: [0, 26],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 26, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 27],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..8f4c003543d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-one Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [8, 16],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [17, 20],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..6763966b08f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,77 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      TSDeclareFunction {
+        type: 'TSDeclareFunction',
+        async: false,
+        declare: true,
+        expression: false,
+        generator: false,
+        id: Identifier {
+          type: 'Identifier',
+          name: 'foo',
+
+          range: [17, 20],
+          loc: {
+            start: { column: 17, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+        params: Array [],
+        typeParameters: TSTypeParameterDeclaration {
+          type: 'TSTypeParameterDeclaration',
+          params: Array [
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'T',
+-
+-               range: [21, 22],
+-               loc: {
+-                 start: { column: 21, line: 1 },
+-                 end: { column: 22, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'T',
+
+              range: [21, 22],
+              loc: {
+                start: { column: 21, line: 1 },
+                end: { column: 22, line: 1 },
+              },
+            },
+          ],
+
+          range: [20, 23],
+          loc: {
+            start: { column: 20, line: 1 },
+            end: { column: 23, line: 1 },
+          },
+        },
+
+        range: [0, 26],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 26, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 27],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..669ef13533f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction type-param-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/fixture.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/fixture.ts
new file mode 100644
index 00000000000..242942bf817
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/fixture.ts
@@ -0,0 +1 @@
+function foo(): void;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..5c46a6508af
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,57 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction without-declare TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+      returnType: TSTypeAnnotation {
+        type: "TSTypeAnnotation",
+        typeAnnotation: TSVoidKeyword {
+          type: "TSVoidKeyword",
+
+          range: [16, 20],
+          loc: {
+            start: { column: 16, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+
+        range: [14, 20],
+        loc: {
+          start: { column: 14, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+
+      range: [0, 21],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 21, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 22],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..67a00cfbc1a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction without-declare TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ":",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "void",
+
+    range: [16, 20],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..2e49a416b76
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/3-Babel-AST.shot
@@ -0,0 +1,57 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction without-declare Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSDeclareFunction {
+      type: "TSDeclareFunction",
+      async: false,
+      expression: false,
+      generator: false,
+      id: Identifier {
+        type: "Identifier",
+        name: "foo",
+
+        range: [9, 12],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+      params: Array [],
+      returnType: TSTypeAnnotation {
+        type: "TSTypeAnnotation",
+        typeAnnotation: TSVoidKeyword {
+          type: "TSVoidKeyword",
+
+          range: [16, 20],
+          loc: {
+            start: { column: 16, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+
+        range: [14, 20],
+        loc: {
+          start: { column: 14, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+
+      range: [0, 21],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 21, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 22],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..0c6751d92ce
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction without-declare Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "function",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "foo",
+
+    range: [9, 12],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ":",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "void",
+
+    range: [16, 20],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..7f5b5b1b141
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction without-declare AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..9995b1b0eb9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/fixtures/without-declare/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSDeclareFunction without-declare AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSDeclareFunction/spec.ts b/packages/ast-spec/src/declaration/TSDeclareFunction/spec.ts
index 88bd4aff2f2..ea37a1e874f 100644
--- a/packages/ast-spec/src/declaration/TSDeclareFunction/spec.ts
+++ b/packages/ast-spec/src/declaration/TSDeclareFunction/spec.ts
@@ -1,6 +1,13 @@
 import type { AST_NODE_TYPES } from '../../ast-node-types';
-import type { FunctionDeclarationBase } from '../../base/FunctionDeclarationBase';
+import type { FunctionBase } from '../../base/FunctionBase';
+import type { BlockStatement } from '../../statement/BlockStatement/spec';
 
-export interface TSDeclareFunction extends FunctionDeclarationBase {
+// TODO(#1852) - async + declare are semantically invalid together
+export interface TSDeclareFunction extends FunctionBase {
   type: AST_NODE_TYPES.TSDeclareFunction;
+  // TODO(#1852) - breaking change enforce this is always `null` like `TSEmptyBodyFunctionExpression`
+  body?: BlockStatement;
+  // TODO(#5020) - make this always `false` if it is not `declare`d instead of `undefined`
+  declare?: boolean;
+  expression: false;
 }
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/fixture.ts b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/fixture.ts
new file mode 100644
index 00000000000..eeaa8c95655
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/fixture.ts
@@ -0,0 +1 @@
+enum Foo;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..89896499476
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration _error_ missing-body TSESTree - Error 1`] = `[TSError: '{' expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..69fc4aef147
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration _error_ missing-body Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:8)]`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..4d1d30b58b6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-body/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration _error_ missing-body Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/fixture.ts b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/fixture.ts
new file mode 100644
index 00000000000..14404051ead
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/fixture.ts
@@ -0,0 +1 @@
+enum {}
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..0653a9025ef
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration _error_ missing-id TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..676c0503e37
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration _error_ missing-id Babel - Error 1`] = `[SyntaxError: Unexpected token (1:5)]`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..5fb97329274
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration _error_ missing-id Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/fixture.ts b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
new file mode 100644
index 00000000000..9089db7067d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
@@ -0,0 +1 @@
+enum 1 {}
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..15a27efccaf
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration _error_ non-identifier-name TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..1cf8f0ab899
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration _error_ non-identifier-name Babel - Error 1`] = `[SyntaxError: Unexpected token (1:5)]`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..dd5c6175008
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration _error_ non-identifier-name Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/fixture.ts b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/fixture.ts
new file mode 100644
index 00000000000..97b096b8754
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/fixture.ts
@@ -0,0 +1 @@
+const enum Foo {}
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..1d59f828b67
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,37 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration const TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSEnumDeclaration {
+      type: "TSEnumDeclaration",
+      const: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [11, 14],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+      members: Array [],
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..a25cddd52f6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration const TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "const",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "enum",
+
+    range: [6, 10],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [11, 14],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..5ee7fea32e6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/3-Babel-AST.shot
@@ -0,0 +1,37 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration const Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSEnumDeclaration {
+      type: "TSEnumDeclaration",
+      const: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [11, 14],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+      members: Array [],
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..4a4ccaf3ecc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration const Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "const",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "enum",
+
+    range: [6, 10],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [11, 14],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..95d4c8f6b4a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration const AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..2e994fa6ae9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/const/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,62 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration const AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+    Keyword {
+      type: 'Keyword',
+      value: 'const',
+
+      range: [0, 5],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 5, line: 1 },
+      },
+    },
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'enum',
+
+      range: [6, 10],
+      loc: {
+        start: { column: 6, line: 1 },
+        end: { column: 10, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'Foo',
+
+      range: [11, 14],
+      loc: {
+        start: { column: 11, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [15, 16],
+      loc: {
+        start: { column: 15, line: 1 },
+        end: { column: 16, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [16, 17],
+      loc: {
+        start: { column: 16, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/fixture.ts b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/fixture.ts
new file mode 100644
index 00000000000..6ec0c1cbf6a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/fixture.ts
@@ -0,0 +1 @@
+declare enum Foo {}
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..8b742184ed9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,37 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration declare TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSEnumDeclaration {
+      type: "TSEnumDeclaration",
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [13, 16],
+        loc: {
+          start: { column: 13, line: 1 },
+          end: { column: 16, line: 1 },
+        },
+      },
+      members: Array [],
+
+      range: [0, 19],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 20],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..b045362a4c5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration declare TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "enum",
+
+    range: [8, 12],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [13, 16],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..21a3e86cd15
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot
@@ -0,0 +1,37 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration declare Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSEnumDeclaration {
+      type: "TSEnumDeclaration",
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [13, 16],
+        loc: {
+          start: { column: 13, line: 1 },
+          end: { column: 16, line: 1 },
+        },
+      },
+      members: Array [],
+
+      range: [0, 19],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 20],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..ccf2a20885e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration declare Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "enum",
+
+    range: [8, 12],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [13, 16],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..5085b6b4609
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration declare AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..11a6693745f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,62 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration declare AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+    Identifier {
+      type: 'Identifier',
+      value: 'declare',
+
+      range: [0, 7],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 7, line: 1 },
+      },
+    },
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'enum',
+
+      range: [8, 12],
+      loc: {
+        start: { column: 8, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'Foo',
+
+      range: [13, 16],
+      loc: {
+        start: { column: 13, line: 1 },
+        end: { column: 16, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [17, 18],
+      loc: {
+        start: { column: 17, line: 1 },
+        end: { column: 18, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [18, 19],
+      loc: {
+        start: { column: 18, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/fixture.ts b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/fixture.ts
new file mode 100644
index 00000000000..f418fb66f4f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/fixture.ts
@@ -0,0 +1 @@
+enum Foo {}
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..85e4f093eb2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,36 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration empty TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSEnumDeclaration {
+      type: "TSEnumDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [5, 8],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      members: Array [],
+
+      range: [0, 11],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 12],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..c419adb8309
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration empty TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "enum",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [5, 8],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..79ad82443c7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/3-Babel-AST.shot
@@ -0,0 +1,36 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration empty Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSEnumDeclaration {
+      type: "TSEnumDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [5, 8],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      members: Array [],
+
+      range: [0, 11],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 12],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..688f75fe0f2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration empty Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "enum",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [5, 8],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..2ce5c714db1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration empty AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..5c9479e0ff8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,52 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration empty AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'enum',
+
+      range: [0, 4],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 4, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'Foo',
+
+      range: [5, 8],
+      loc: {
+        start: { column: 5, line: 1 },
+        end: { column: 8, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [9, 10],
+      loc: {
+        start: { column: 9, line: 1 },
+        end: { column: 10, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [10, 11],
+      loc: {
+        start: { column: 10, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/fixture.ts b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/fixture.ts
new file mode 100644
index 00000000000..a639ff46e1b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/fixture.ts
@@ -0,0 +1,3 @@
+enum Foo {
+  A,
+}
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..dc9b0027eed
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration with-member-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSEnumDeclaration {
+      type: "TSEnumDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [5, 8],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      members: Array [
+        TSEnumMember {
+          type: "TSEnumMember",
+          id: Identifier {
+            type: "Identifier",
+            name: "A",
+
+            range: [13, 14],
+            loc: {
+              start: { column: 2, line: 2 },
+              end: { column: 3, line: 2 },
+            },
+          },
+
+          range: [13, 14],
+          loc: {
+            start: { column: 2, line: 2 },
+            end: { column: 3, line: 2 },
+          },
+        },
+      ],
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 1, line: 3 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 4 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..e0ddd7d58be
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration with-member-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "enum",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [5, 8],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 2, line: 2 },
+      end: { column: 3, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 3, line: 2 },
+      end: { column: 4, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 0, line: 3 },
+      end: { column: 1, line: 3 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..47761319694
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration with-member-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSEnumDeclaration {
+      type: "TSEnumDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [5, 8],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      members: Array [
+        TSEnumMember {
+          type: "TSEnumMember",
+          id: Identifier {
+            type: "Identifier",
+            name: "A",
+
+            range: [13, 14],
+            loc: {
+              start: { column: 2, line: 2 },
+              end: { column: 3, line: 2 },
+            },
+          },
+
+          range: [13, 14],
+          loc: {
+            start: { column: 2, line: 2 },
+            end: { column: 3, line: 2 },
+          },
+        },
+      ],
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 1, line: 3 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 4 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..08d14feb8c4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration with-member-one Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "enum",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [5, 8],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 2, line: 2 },
+      end: { column: 3, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 3, line: 2 },
+      end: { column: 4, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 0, line: 3 },
+      end: { column: 1, line: 3 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..b707fc5d46b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration with-member-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..cf146a98eac
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/fixtures/with-member-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,72 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSEnumDeclaration with-member-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'enum',
+
+      range: [0, 4],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 4, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'Foo',
+
+      range: [5, 8],
+      loc: {
+        start: { column: 5, line: 1 },
+        end: { column: 8, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [9, 10],
+      loc: {
+        start: { column: 9, line: 1 },
+        end: { column: 10, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'A',
+
+      range: [13, 14],
+      loc: {
+        start: { column: 2, line: 2 },
+        end: { column: 3, line: 2 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ',',
+
+      range: [14, 15],
+      loc: {
+        start: { column: 3, line: 2 },
+        end: { column: 4, line: 2 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [16, 17],
+      loc: {
+        start: { column: 0, line: 3 },
+        end: { column: 1, line: 3 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSEnumDeclaration/spec.ts b/packages/ast-spec/src/declaration/TSEnumDeclaration/spec.ts
index 1c1530d501f..9a0df845c5d 100644
--- a/packages/ast-spec/src/declaration/TSEnumDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/TSEnumDeclaration/spec.ts
@@ -6,9 +6,30 @@ import type { Modifier } from '../../unions/Modifier';
 
 export interface TSEnumDeclaration extends BaseNode {
   type: AST_NODE_TYPES.TSEnumDeclaration;
-  id: Identifier;
-  members: TSEnumMember[];
+  /**
+   * Whether this is a `const` enum.
+   * ```
+   * const enum Foo {...}
+   * ```
+   */
+  // TODO(#5020) - make this `false` if it is not `const`
   const?: boolean;
+  /**
+   * Whether this is a `declare`d enum.
+   * ```
+   * declare enum Foo {...}
+   * ```
+   */
+  // TODO(#5020) - make this `false` if it is not `declare`d
   declare?: boolean;
+  /**
+   * The enum name.
+   */
+  id: Identifier;
+  /**
+   * The enum members.
+   */
+  members: TSEnumMember[];
+  // TODO(#4759) - breaking change remove this
   modifiers?: Modifier[];
 }
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/fixture.ts b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/fixture.ts
new file mode 100644
index 00000000000..7fe439305a4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/fixture.ts
@@ -0,0 +1 @@
+import F = 1;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..3593291fdb2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ entity-name-invalid TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..d5cc0b77735
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ entity-name-invalid Babel - Error 1`] = `[SyntaxError: Unexpected token (1:11)]`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..463142c713f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/entity-name-invalid/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ entity-name-invalid Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/fixture.ts b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/fixture.ts
new file mode 100644
index 00000000000..b67ea934e8c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/fixture.ts
@@ -0,0 +1 @@
+import F = require(1);
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..51aedf5fa31
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ external-module-ref-non-string TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..b19940abe31
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ external-module-ref-non-string Babel - Error 1`] = `[SyntaxError: Unexpected token (1:19)]`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..cda96c9ac3d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ external-module-ref-non-string Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/fixture.ts b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/fixture.ts
new file mode 100644
index 00000000000..769999c5f68
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/fixture.ts
@@ -0,0 +1,2 @@
+type T = 1;
+import type F = T;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..387be14ced2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ import-kind TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..b8f9e5be4e4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ import-kind Babel - Error 1`] = `[SyntaxError: An import alias can not use 'import type'. (2:16)]`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..d9472dcc7b6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ import-kind Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/fixture.ts b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/fixture.ts
new file mode 100644
index 00000000000..2b0ead218dd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/fixture.ts
@@ -0,0 +1 @@
+import = A.B;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..b5dc03a804c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ missing-id TSESTree - Error 1`] = `[TSError: Declaration or statement expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..3c24250cf63
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ missing-id Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:7)]`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..3f9e697fc06
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ missing-id Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/fixture.ts b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/fixture.ts
new file mode 100644
index 00000000000..3ce78a91241
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/fixture.ts
@@ -0,0 +1 @@
+import F;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..cb33fd8279b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ missing-reference TSESTree - Error 1`] = `[TSError: '=' expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..6dcc0a59954
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ missing-reference Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "from" (1:8)]`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..7a3b4167a3b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/_error_/missing-reference/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration _error_ missing-reference Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/fixture.ts b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/fixture.ts
new file mode 100644
index 00000000000..fdcbe7ffe41
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/fixture.ts
@@ -0,0 +1 @@
+import F = A.B.C;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..6d438a8c596
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,85 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSImportEqualsDeclaration {
+      type: "TSImportEqualsDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      importKind: "value",
+      isExport: false,
+      moduleReference: TSQualifiedName {
+        type: "TSQualifiedName",
+        left: TSQualifiedName {
+          type: "TSQualifiedName",
+          left: Identifier {
+            type: "Identifier",
+            name: "A",
+
+            range: [11, 12],
+            loc: {
+              start: { column: 11, line: 1 },
+              end: { column: 12, line: 1 },
+            },
+          },
+          right: Identifier {
+            type: "Identifier",
+            name: "B",
+
+            range: [13, 14],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 14, line: 1 },
+            },
+          },
+
+          range: [11, 14],
+          loc: {
+            start: { column: 11, line: 1 },
+            end: { column: 14, line: 1 },
+          },
+        },
+        right: Identifier {
+          type: "Identifier",
+          name: "C",
+
+          range: [15, 16],
+          loc: {
+            start: { column: 15, line: 1 },
+            end: { column: 16, line: 1 },
+          },
+        },
+
+        range: [11, 16],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 16, line: 1 },
+        },
+      },
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..7d0291e8b8b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-many TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "B",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "C",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..e4d68bb9f75
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,85 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSImportEqualsDeclaration {
+      type: "TSImportEqualsDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      importKind: "value",
+      isExport: false,
+      moduleReference: TSQualifiedName {
+        type: "TSQualifiedName",
+        left: TSQualifiedName {
+          type: "TSQualifiedName",
+          left: Identifier {
+            type: "Identifier",
+            name: "A",
+
+            range: [11, 12],
+            loc: {
+              start: { column: 11, line: 1 },
+              end: { column: 12, line: 1 },
+            },
+          },
+          right: Identifier {
+            type: "Identifier",
+            name: "B",
+
+            range: [13, 14],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 14, line: 1 },
+            },
+          },
+
+          range: [11, 14],
+          loc: {
+            start: { column: 11, line: 1 },
+            end: { column: 14, line: 1 },
+          },
+        },
+        right: Identifier {
+          type: "Identifier",
+          name: "C",
+
+          range: [15, 16],
+          loc: {
+            start: { column: 15, line: 1 },
+            end: { column: 16, line: 1 },
+          },
+        },
+
+        range: [11, 16],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 16, line: 1 },
+        },
+      },
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..08ed3e892d5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-many Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "B",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "C",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..88ec007b237
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..b006c4e07d2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/fixture.ts b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/fixture.ts
new file mode 100644
index 00000000000..ac623ee9e28
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/fixture.ts
@@ -0,0 +1 @@
+import F = A;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..aa18656723b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,47 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSImportEqualsDeclaration {
+      type: "TSImportEqualsDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      importKind: "value",
+      isExport: false,
+      moduleReference: Identifier {
+        type: "Identifier",
+        name: "A",
+
+        range: [11, 12],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+
+      range: [0, 13],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 14],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..1e7f3ae9a45
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..d6e2ea9ed20
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,47 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSImportEqualsDeclaration {
+      type: "TSImportEqualsDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      importKind: "value",
+      isExport: false,
+      moduleReference: Identifier {
+        type: "Identifier",
+        name: "A",
+
+        range: [11, 12],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 12, line: 1 },
+        },
+      },
+
+      range: [0, 13],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 14],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..85b199a73a4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-one Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..0cb17969d4f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..28d07eeb473
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/entity-name-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration entity-name-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/fixture.ts b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/fixture.ts
new file mode 100644
index 00000000000..2c8ef7abf25
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/fixture.ts
@@ -0,0 +1 @@
+import F = require('mod');
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..aca9d9ab5f3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,57 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration external-module-ref-string TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSImportEqualsDeclaration {
+      type: "TSImportEqualsDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      importKind: "value",
+      isExport: false,
+      moduleReference: TSExternalModuleReference {
+        type: "TSExternalModuleReference",
+        expression: Literal {
+          type: "Literal",
+          raw: "'mod'",
+          value: "mod",
+
+          range: [19, 24],
+          loc: {
+            start: { column: 19, line: 1 },
+            end: { column: 24, line: 1 },
+          },
+        },
+
+        range: [11, 25],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 25, line: 1 },
+        },
+      },
+
+      range: [0, 26],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 26, line: 1 },
+      },
+    },
+  ],
+  sourceType: "module",
+
+  range: [0, 27],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..023028ef7d9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration external-module-ref-string TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "require",
+
+    range: [11, 18],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [19, 24],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..f904ff1dbcf
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/3-Babel-AST.shot
@@ -0,0 +1,57 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration external-module-ref-string Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSImportEqualsDeclaration {
+      type: "TSImportEqualsDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+      importKind: "value",
+      isExport: false,
+      moduleReference: TSExternalModuleReference {
+        type: "TSExternalModuleReference",
+        expression: Literal {
+          type: "Literal",
+          raw: "'mod'",
+          value: "mod",
+
+          range: [19, 24],
+          loc: {
+            start: { column: 19, line: 1 },
+            end: { column: 24, line: 1 },
+          },
+        },
+
+        range: [11, 25],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 25, line: 1 },
+        },
+      },
+
+      range: [0, 26],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 26, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 27],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..91b65568fbe
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration external-module-ref-string Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "import",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "require",
+
+    range: [11, 18],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "(",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'mod'",
+
+    range: [19, 24],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ")",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [25, 26],
+    loc: {
+      start: { column: 25, line: 1 },
+      end: { column: 26, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..a0b231ec7a1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,62 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration external-module-ref-string AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      TSImportEqualsDeclaration {
+        type: 'TSImportEqualsDeclaration',
+        id: Identifier {
+          type: 'Identifier',
+          name: 'F',
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+        importKind: 'value',
+        isExport: false,
+        moduleReference: TSExternalModuleReference {
+          type: 'TSExternalModuleReference',
+          expression: Literal {
+            type: 'Literal',
+            raw: '\\\\'mod\\\\'',
+            value: 'mod',
+
+            range: [19, 24],
+            loc: {
+              start: { column: 19, line: 1 },
+              end: { column: 24, line: 1 },
+            },
+          },
+
+          range: [11, 25],
+          loc: {
+            start: { column: 11, line: 1 },
+            end: { column: 25, line: 1 },
+          },
+        },
+
+        range: [0, 26],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 26, line: 1 },
+        },
+      },
+    ],
+-   sourceType: 'module',
++   sourceType: 'script',
+
+    range: [0, 27],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..ce5e5680101
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSImportEqualsDeclaration external-module-ref-string AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/spec.ts b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/spec.ts
index 5ccd9b6fc4f..d4db9a64168 100644
--- a/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/TSImportEqualsDeclaration/spec.ts
@@ -7,8 +7,27 @@ import type { ImportKind } from '../ExportAndImportKind';
 
 export interface TSImportEqualsDeclaration extends BaseNode {
   type: AST_NODE_TYPES.TSImportEqualsDeclaration;
+  /**
+   * The locally imported name
+   */
   id: Identifier;
+  /**
+   * The value being aliased.
+   * ```
+   * import F1 = A;
+   * import F2 = A.B.C;
+   * import F3 = require('mod');
+   * ```
+   */
   moduleReference: EntityName | TSExternalModuleReference;
+  // TODO(#1852) - breaking change remove this as it is invalid
   importKind: ImportKind;
+  /**
+   * Whether this is immediately exported
+   * ```
+   * export import F = A;
+   * ```
+   */
+  // TODO(#4130) - this should be represented in the AST
   isExport: boolean;
 }
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/fixture.ts
new file mode 100644
index 00000000000..b3123630664
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/fixture.ts
@@ -0,0 +1 @@
+interface F;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..128274dff58
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-body TSESTree - Error 1`] = `[TSError: '{' expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..12baf6e0738
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-body Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:11)]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..6caba1ae72c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-body/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-body Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/fixture.ts
new file mode 100644
index 00000000000..74fde08aea1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/fixture.ts
@@ -0,0 +1 @@
+interface F extends {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..a33eb58a06d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-extends TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..add92930a37
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-extends Babel - Error 1`] = `[SyntaxError: 'extends' list cannot be empty. (1:20)]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..6eb1bf9104f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-extends Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/fixture.ts
new file mode 100644
index 00000000000..6b562c272fc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/fixture.ts
@@ -0,0 +1 @@
+interface {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..d640ad78d53
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-id TSESTree - Error 1`] = `[TSError: Interface must be given a name.]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..e06bfcc1a1c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-id Babel - Error 1`] = `[SyntaxError: 'interface' declarations must be followed by an identifier. (1:10)]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..bbce8c51c4d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-id Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/fixture.ts
new file mode 100644
index 00000000000..f03a31c78c2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/fixture.ts
@@ -0,0 +1 @@
+interface F<> {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..9d0be0712d4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-type-param TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..936edbec8c8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-type-param Babel - Error 1`] = `[SyntaxError: Type parameter list cannot be empty. (1:11)]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..5846179dd56
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ missing-type-param Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/fixture.ts
new file mode 100644
index 00000000000..c649bd49662
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/fixture.ts
@@ -0,0 +1 @@
+interface F extends 1 {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..e8e8c0e5fdb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ non-identifier-extends TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..e7b584a9cd2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ non-identifier-extends Babel - Error 1`] = `[SyntaxError: Unexpected token (1:20)]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..c429168c288
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ non-identifier-extends Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
new file mode 100644
index 00000000000..7b8c5e961ee
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
@@ -0,0 +1 @@
+interface 1 {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..7b6a2f0a666
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ non-identifier-name TSESTree - Error 1`] = `[TSError: Interface name cannot be '1'.]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..64f544addb3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ non-identifier-name Babel - Error 1`] = `[SyntaxError: 'interface' declarations must be followed by an identifier. (1:10)]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..5470a1ec04e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ non-identifier-name Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/fixture.ts
new file mode 100644
index 00000000000..2809a08b8cf
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/fixture.ts
@@ -0,0 +1 @@
+interface F<1> {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..e48629574cf
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ non-identifier-type-param TSESTree - Error 1`] = `[TSError: Type parameter declaration expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..69166a9fa11
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ non-identifier-type-param Babel - Error 1`] = `[SyntaxError: Unexpected token (1:12)]`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..5f1be010c62
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-type-param/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration _error_ non-identifier-type-param Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/fixture.ts
new file mode 100644
index 00000000000..0e8aa5a3479
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/fixture.ts
@@ -0,0 +1 @@
+declare interface F {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..501d609a46c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration declare TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [20, 22],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 22, line: 1 },
+        },
+      },
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [18, 19],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+
+      range: [0, 22],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 22, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 23],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..8899a66c8a3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration declare TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "interface",
+
+    range: [8, 17],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..4642a30ee6d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration declare Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [20, 22],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 22, line: 1 },
+        },
+      },
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [18, 19],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+
+      range: [0, 22],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 22, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 23],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..b75639c632d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration declare Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "interface",
+
+    range: [8, 17],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..c5bfaba693b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration declare AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..057cff33527
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,62 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration declare AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+    Identifier {
+      type: 'Identifier',
+      value: 'declare',
+
+      range: [0, 7],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 7, line: 1 },
+      },
+    },
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'interface',
+
+      range: [8, 17],
+      loc: {
+        start: { column: 8, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'F',
+
+      range: [18, 19],
+      loc: {
+        start: { column: 18, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [20, 21],
+      loc: {
+        start: { column: 20, line: 1 },
+        end: { column: 21, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [21, 22],
+      loc: {
+        start: { column: 21, line: 1 },
+        end: { column: 22, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/fixture.ts
new file mode 100644
index 00000000000..296dc32043f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/fixture.ts
@@ -0,0 +1 @@
+interface F {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..aa7db317692
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,45 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration empty TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [12, 14],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 14],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 15],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..b46401c8187
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration empty TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..e6048d6bde4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/3-Babel-AST.shot
@@ -0,0 +1,45 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration empty Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [12, 14],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 14],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 15],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..01311e4df0c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration empty Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..42bc3c4eb68
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration empty AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..68a5be8dd4f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/empty/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,52 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration empty AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'interface',
+
+      range: [0, 9],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 9, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'F',
+
+      range: [10, 11],
+      loc: {
+        start: { column: 10, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [12, 13],
+      loc: {
+        start: { column: 12, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [13, 14],
+      loc: {
+        start: { column: 13, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/fixture.ts
new file mode 100644
index 00000000000..a0c396132b5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/fixture.ts
@@ -0,0 +1 @@
+interface F extends A, B, C {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..2e08532845c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,104 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [28, 30],
+        loc: {
+          start: { column: 28, line: 1 },
+          end: { column: 30, line: 1 },
+        },
+      },
+      extends: Array [
+        TSInterfaceHeritage {
+          type: "TSInterfaceHeritage",
+          expression: Identifier {
+            type: "Identifier",
+            name: "A",
+
+            range: [20, 21],
+            loc: {
+              start: { column: 20, line: 1 },
+              end: { column: 21, line: 1 },
+            },
+          },
+
+          range: [20, 21],
+          loc: {
+            start: { column: 20, line: 1 },
+            end: { column: 21, line: 1 },
+          },
+        },
+        TSInterfaceHeritage {
+          type: "TSInterfaceHeritage",
+          expression: Identifier {
+            type: "Identifier",
+            name: "B",
+
+            range: [23, 24],
+            loc: {
+              start: { column: 23, line: 1 },
+              end: { column: 24, line: 1 },
+            },
+          },
+
+          range: [23, 24],
+          loc: {
+            start: { column: 23, line: 1 },
+            end: { column: 24, line: 1 },
+          },
+        },
+        TSInterfaceHeritage {
+          type: "TSInterfaceHeritage",
+          expression: Identifier {
+            type: "Identifier",
+            name: "C",
+
+            range: [26, 27],
+            loc: {
+              start: { column: 26, line: 1 },
+              end: { column: 27, line: 1 },
+            },
+          },
+
+          range: [26, 27],
+          loc: {
+            start: { column: 26, line: 1 },
+            end: { column: 27, line: 1 },
+          },
+        },
+      ],
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 30],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 30, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 31],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..b5418859abc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,106 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-many TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "extends",
+
+    range: [12, 19],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "B",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "C",
+
+    range: [26, 27],
+    loc: {
+      start: { column: 26, line: 1 },
+      end: { column: 27, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [28, 29],
+    loc: {
+      start: { column: 28, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 29, line: 1 },
+      end: { column: 30, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..18e1c620074
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,104 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [28, 30],
+        loc: {
+          start: { column: 28, line: 1 },
+          end: { column: 30, line: 1 },
+        },
+      },
+      extends: Array [
+        TSExpressionWithTypeArguments {
+          type: "TSExpressionWithTypeArguments",
+          expression: Identifier {
+            type: "Identifier",
+            name: "A",
+
+            range: [20, 21],
+            loc: {
+              start: { column: 20, line: 1 },
+              end: { column: 21, line: 1 },
+            },
+          },
+
+          range: [20, 21],
+          loc: {
+            start: { column: 20, line: 1 },
+            end: { column: 21, line: 1 },
+          },
+        },
+        TSExpressionWithTypeArguments {
+          type: "TSExpressionWithTypeArguments",
+          expression: Identifier {
+            type: "Identifier",
+            name: "B",
+
+            range: [23, 24],
+            loc: {
+              start: { column: 23, line: 1 },
+              end: { column: 24, line: 1 },
+            },
+          },
+
+          range: [23, 24],
+          loc: {
+            start: { column: 23, line: 1 },
+            end: { column: 24, line: 1 },
+          },
+        },
+        TSExpressionWithTypeArguments {
+          type: "TSExpressionWithTypeArguments",
+          expression: Identifier {
+            type: "Identifier",
+            name: "C",
+
+            range: [26, 27],
+            loc: {
+              start: { column: 26, line: 1 },
+              end: { column: 27, line: 1 },
+            },
+          },
+
+          range: [26, 27],
+          loc: {
+            start: { column: 26, line: 1 },
+            end: { column: 27, line: 1 },
+          },
+        },
+      ],
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 30],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 30, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 31],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..c6f5129d13f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,106 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-many Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "extends",
+
+    range: [12, 19],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "B",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [24, 25],
+    loc: {
+      start: { column: 24, line: 1 },
+      end: { column: 25, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "C",
+
+    range: [26, 27],
+    loc: {
+      start: { column: 26, line: 1 },
+      end: { column: 27, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [28, 29],
+    loc: {
+      start: { column: 28, line: 1 },
+      end: { column: 29, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [29, 30],
+    loc: {
+      start: { column: 29, line: 1 },
+      end: { column: 30, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..793c00b7e98
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,114 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      TSInterfaceDeclaration {
+        type: 'TSInterfaceDeclaration',
+        body: TSInterfaceBody {
+          type: 'TSInterfaceBody',
+          body: Array [],
+
+          range: [28, 30],
+          loc: {
+            start: { column: 28, line: 1 },
+            end: { column: 30, line: 1 },
+          },
+        },
+        extends: Array [
+-         TSInterfaceHeritage {
+-           type: 'TSInterfaceHeritage',
++         TSExpressionWithTypeArguments {
++           type: 'TSExpressionWithTypeArguments',
+            expression: Identifier {
+              type: 'Identifier',
+              name: 'A',
+
+              range: [20, 21],
+              loc: {
+                start: { column: 20, line: 1 },
+                end: { column: 21, line: 1 },
+              },
+            },
+
+            range: [20, 21],
+            loc: {
+              start: { column: 20, line: 1 },
+              end: { column: 21, line: 1 },
+            },
+          },
+-         TSInterfaceHeritage {
+-           type: 'TSInterfaceHeritage',
++         TSExpressionWithTypeArguments {
++           type: 'TSExpressionWithTypeArguments',
+            expression: Identifier {
+              type: 'Identifier',
+              name: 'B',
+
+              range: [23, 24],
+              loc: {
+                start: { column: 23, line: 1 },
+                end: { column: 24, line: 1 },
+              },
+            },
+
+            range: [23, 24],
+            loc: {
+              start: { column: 23, line: 1 },
+              end: { column: 24, line: 1 },
+            },
+          },
+-         TSInterfaceHeritage {
+-           type: 'TSInterfaceHeritage',
++         TSExpressionWithTypeArguments {
++           type: 'TSExpressionWithTypeArguments',
+            expression: Identifier {
+              type: 'Identifier',
+              name: 'C',
+
+              range: [26, 27],
+              loc: {
+                start: { column: 26, line: 1 },
+                end: { column: 27, line: 1 },
+              },
+            },
+
+            range: [26, 27],
+            loc: {
+              start: { column: 26, line: 1 },
+              end: { column: 27, line: 1 },
+            },
+          },
+        ],
+        id: Identifier {
+          type: 'Identifier',
+          name: 'F',
+
+          range: [10, 11],
+          loc: {
+            start: { column: 10, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+
+        range: [0, 30],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 30, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 31],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..c6ea1aca49b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,112 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'interface',
+
+      range: [0, 9],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 9, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'F',
+
+      range: [10, 11],
+      loc: {
+        start: { column: 10, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+    Keyword {
+      type: 'Keyword',
+      value: 'extends',
+
+      range: [12, 19],
+      loc: {
+        start: { column: 12, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'A',
+
+      range: [20, 21],
+      loc: {
+        start: { column: 20, line: 1 },
+        end: { column: 21, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ',',
+
+      range: [21, 22],
+      loc: {
+        start: { column: 21, line: 1 },
+        end: { column: 22, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'B',
+
+      range: [23, 24],
+      loc: {
+        start: { column: 23, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ',',
+
+      range: [24, 25],
+      loc: {
+        start: { column: 24, line: 1 },
+        end: { column: 25, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'C',
+
+      range: [26, 27],
+      loc: {
+        start: { column: 26, line: 1 },
+        end: { column: 27, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [28, 29],
+      loc: {
+        start: { column: 28, line: 1 },
+        end: { column: 29, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [29, 30],
+      loc: {
+        start: { column: 29, line: 1 },
+        end: { column: 30, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/fixture.ts
new file mode 100644
index 00000000000..cd5394400b5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/fixture.ts
@@ -0,0 +1 @@
+interface F extends A {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..795dc661bbe
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [22, 24],
+        loc: {
+          start: { column: 22, line: 1 },
+          end: { column: 24, line: 1 },
+        },
+      },
+      extends: Array [
+        TSInterfaceHeritage {
+          type: "TSInterfaceHeritage",
+          expression: Identifier {
+            type: "Identifier",
+            name: "A",
+
+            range: [20, 21],
+            loc: {
+              start: { column: 20, line: 1 },
+              end: { column: 21, line: 1 },
+            },
+          },
+
+          range: [20, 21],
+          loc: {
+            start: { column: 20, line: 1 },
+            end: { column: 21, line: 1 },
+          },
+        },
+      ],
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..b9e3f8a240d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "extends",
+
+    range: [12, 19],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..87260af0dd5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [22, 24],
+        loc: {
+          start: { column: 22, line: 1 },
+          end: { column: 24, line: 1 },
+        },
+      },
+      extends: Array [
+        TSExpressionWithTypeArguments {
+          type: "TSExpressionWithTypeArguments",
+          expression: Identifier {
+            type: "Identifier",
+            name: "A",
+
+            range: [20, 21],
+            loc: {
+              start: { column: 20, line: 1 },
+              end: { column: 21, line: 1 },
+            },
+          },
+
+          range: [20, 21],
+          loc: {
+            start: { column: 20, line: 1 },
+            end: { column: 21, line: 1 },
+          },
+        },
+      ],
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 24],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 25],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..26da7a11f7c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-one Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "extends",
+
+    range: [12, 19],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [23, 24],
+    loc: {
+      start: { column: 23, line: 1 },
+      end: { column: 24, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..fe6cf12f1a5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,72 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      TSInterfaceDeclaration {
+        type: 'TSInterfaceDeclaration',
+        body: TSInterfaceBody {
+          type: 'TSInterfaceBody',
+          body: Array [],
+
+          range: [22, 24],
+          loc: {
+            start: { column: 22, line: 1 },
+            end: { column: 24, line: 1 },
+          },
+        },
+        extends: Array [
+-         TSInterfaceHeritage {
+-           type: 'TSInterfaceHeritage',
++         TSExpressionWithTypeArguments {
++           type: 'TSExpressionWithTypeArguments',
+            expression: Identifier {
+              type: 'Identifier',
+              name: 'A',
+
+              range: [20, 21],
+              loc: {
+                start: { column: 20, line: 1 },
+                end: { column: 21, line: 1 },
+              },
+            },
+
+            range: [20, 21],
+            loc: {
+              start: { column: 20, line: 1 },
+              end: { column: 21, line: 1 },
+            },
+          },
+        ],
+        id: Identifier {
+          type: 'Identifier',
+          name: 'F',
+
+          range: [10, 11],
+          loc: {
+            start: { column: 10, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+
+        range: [0, 24],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 24, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 25],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..f12bb69db9b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/extends-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,72 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration extends-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'interface',
+
+      range: [0, 9],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 9, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'F',
+
+      range: [10, 11],
+      loc: {
+        start: { column: 10, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+    Keyword {
+      type: 'Keyword',
+      value: 'extends',
+
+      range: [12, 19],
+      loc: {
+        start: { column: 12, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'A',
+
+      range: [20, 21],
+      loc: {
+        start: { column: 20, line: 1 },
+        end: { column: 21, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [22, 23],
+      loc: {
+        start: { column: 22, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [23, 24],
+      loc: {
+        start: { column: 23, line: 1 },
+        end: { column: 24, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/fixture.ts
new file mode 100644
index 00000000000..82042ece0e3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/fixture.ts
@@ -0,0 +1 @@
+interface F<T, U, V> {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..6aea3322462
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,119 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [21, 23],
+        loc: {
+          start: { column: 21, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "T",
+
+              range: [12, 13],
+              loc: {
+                start: { column: 12, line: 1 },
+                end: { column: 13, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "U",
+
+              range: [15, 16],
+              loc: {
+                start: { column: 15, line: 1 },
+                end: { column: 16, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "V",
+
+              range: [18, 19],
+              loc: {
+                start: { column: 18, line: 1 },
+                end: { column: 19, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [18, 19],
+            loc: {
+              start: { column: 18, line: 1 },
+              end: { column: 19, line: 1 },
+            },
+          },
+        ],
+
+        range: [11, 20],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..d96cb3d9489
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,116 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-many TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "V",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..579e9191d10
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [21, 23],
+        loc: {
+          start: { column: 21, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "T",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "U",
+
+            range: [15, 16],
+            loc: {
+              start: { column: 15, line: 1 },
+              end: { column: 16, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "V",
+
+            range: [18, 19],
+            loc: {
+              start: { column: 18, line: 1 },
+              end: { column: 19, line: 1 },
+            },
+          },
+        ],
+
+        range: [11, 20],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..174304a412f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,116 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-many Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "V",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 22, line: 1 },
+      end: { column: 23, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..56e43bd6632
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,126 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      TSInterfaceDeclaration {
+        type: 'TSInterfaceDeclaration',
+        body: TSInterfaceBody {
+          type: 'TSInterfaceBody',
+          body: Array [],
+
+          range: [21, 23],
+          loc: {
+            start: { column: 21, line: 1 },
+            end: { column: 23, line: 1 },
+          },
+        },
+        id: Identifier {
+          type: 'Identifier',
+          name: 'F',
+
+          range: [10, 11],
+          loc: {
+            start: { column: 10, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+        typeParameters: TSTypeParameterDeclaration {
+          type: 'TSTypeParameterDeclaration',
+          params: Array [
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'T',
+-
+-               range: [12, 13],
+-               loc: {
+-                 start: { column: 12, line: 1 },
+-                 end: { column: 13, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'T',
+
+              range: [12, 13],
+              loc: {
+                start: { column: 12, line: 1 },
+                end: { column: 13, line: 1 },
+              },
+            },
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'U',
+-
+-               range: [15, 16],
+-               loc: {
+-                 start: { column: 15, line: 1 },
+-                 end: { column: 16, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'U',
+
+              range: [15, 16],
+              loc: {
+                start: { column: 15, line: 1 },
+                end: { column: 16, line: 1 },
+              },
+            },
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'V',
+-
+-               range: [18, 19],
+-               loc: {
+-                 start: { column: 18, line: 1 },
+-                 end: { column: 19, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'V',
+
+              range: [18, 19],
+              loc: {
+                start: { column: 18, line: 1 },
+                end: { column: 19, line: 1 },
+              },
+            },
+          ],
+
+          range: [11, 20],
+          loc: {
+            start: { column: 11, line: 1 },
+            end: { column: 20, line: 1 },
+          },
+        },
+
+        range: [0, 23],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 23, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 24],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..889b7b8eba0
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,122 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'interface',
+
+      range: [0, 9],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 9, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'F',
+
+      range: [10, 11],
+      loc: {
+        start: { column: 10, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '<',
+
+      range: [11, 12],
+      loc: {
+        start: { column: 11, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'T',
+
+      range: [12, 13],
+      loc: {
+        start: { column: 12, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ',',
+
+      range: [13, 14],
+      loc: {
+        start: { column: 13, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'U',
+
+      range: [15, 16],
+      loc: {
+        start: { column: 15, line: 1 },
+        end: { column: 16, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ',',
+
+      range: [16, 17],
+      loc: {
+        start: { column: 16, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'V',
+
+      range: [18, 19],
+      loc: {
+        start: { column: 18, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '>',
+
+      range: [19, 20],
+      loc: {
+        start: { column: 19, line: 1 },
+        end: { column: 20, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [21, 22],
+      loc: {
+        start: { column: 21, line: 1 },
+        end: { column: 22, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [22, 23],
+      loc: {
+        start: { column: 22, line: 1 },
+        end: { column: 23, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/fixture.ts
new file mode 100644
index 00000000000..abd3720f1a6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/fixture.ts
@@ -0,0 +1 @@
+interface F<T> {}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..15f67448566
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,77 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [15, 17],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 17, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "T",
+
+              range: [12, 13],
+              loc: {
+                start: { column: 12, line: 1 },
+                end: { column: 13, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+        ],
+
+        range: [11, 14],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..d88a78ec400
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..dc81d623ecc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [],
+
+        range: [15, 17],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 17, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "T",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+        ],
+
+        range: [11, 14],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..a41373677b1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-one Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..d6859d52b51
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,82 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      TSInterfaceDeclaration {
+        type: 'TSInterfaceDeclaration',
+        body: TSInterfaceBody {
+          type: 'TSInterfaceBody',
+          body: Array [],
+
+          range: [15, 17],
+          loc: {
+            start: { column: 15, line: 1 },
+            end: { column: 17, line: 1 },
+          },
+        },
+        id: Identifier {
+          type: 'Identifier',
+          name: 'F',
+
+          range: [10, 11],
+          loc: {
+            start: { column: 10, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+        typeParameters: TSTypeParameterDeclaration {
+          type: 'TSTypeParameterDeclaration',
+          params: Array [
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'T',
+-
+-               range: [12, 13],
+-               loc: {
+-                 start: { column: 12, line: 1 },
+-                 end: { column: 13, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'T',
+
+              range: [12, 13],
+              loc: {
+                start: { column: 12, line: 1 },
+                end: { column: 13, line: 1 },
+              },
+            },
+          ],
+
+          range: [11, 14],
+          loc: {
+            start: { column: 11, line: 1 },
+            end: { column: 14, line: 1 },
+          },
+        },
+
+        range: [0, 17],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 17, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 18],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..fc20247a46e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,82 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration type-param-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'interface',
+
+      range: [0, 9],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 9, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'F',
+
+      range: [10, 11],
+      loc: {
+        start: { column: 10, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '<',
+
+      range: [11, 12],
+      loc: {
+        start: { column: 11, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'T',
+
+      range: [12, 13],
+      loc: {
+        start: { column: 12, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '>',
+
+      range: [13, 14],
+      loc: {
+        start: { column: 13, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [15, 16],
+      loc: {
+        start: { column: 15, line: 1 },
+        end: { column: 16, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [16, 17],
+      loc: {
+        start: { column: 16, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/fixture.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/fixture.ts
new file mode 100644
index 00000000000..2f47465c4e0
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/fixture.ts
@@ -0,0 +1,3 @@
+interface F {
+  prop;
+}
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..424cf585b19
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration with-member-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [
+          TSPropertySignature {
+            type: "TSPropertySignature",
+            computed: false,
+            key: Identifier {
+              type: "Identifier",
+              name: "prop",
+
+              range: [16, 20],
+              loc: {
+                start: { column: 2, line: 2 },
+                end: { column: 6, line: 2 },
+              },
+            },
+
+            range: [16, 21],
+            loc: {
+              start: { column: 2, line: 2 },
+              end: { column: 7, line: 2 },
+            },
+          },
+        ],
+
+        range: [12, 23],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 1, line: 3 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 1, line: 3 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 4 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..c57ff756e66
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration with-member-one TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "prop",
+
+    range: [16, 20],
+    loc: {
+      start: { column: 2, line: 2 },
+      end: { column: 6, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 6, line: 2 },
+      end: { column: 7, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 0, line: 3 },
+      end: { column: 1, line: 3 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..94437c371ec
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration with-member-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSInterfaceDeclaration {
+      type: "TSInterfaceDeclaration",
+      body: TSInterfaceBody {
+        type: "TSInterfaceBody",
+        body: Array [
+          TSPropertySignature {
+            type: "TSPropertySignature",
+            computed: false,
+            key: Identifier {
+              type: "Identifier",
+              name: "prop",
+
+              range: [16, 20],
+              loc: {
+                start: { column: 2, line: 2 },
+                end: { column: 6, line: 2 },
+              },
+            },
+
+            range: [16, 21],
+            loc: {
+              start: { column: 2, line: 2 },
+              end: { column: 7, line: 2 },
+            },
+          },
+        ],
+
+        range: [12, 23],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 1, line: 3 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 23],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 1, line: 3 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 24],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 4 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..af379bd7026
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration with-member-one Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "interface",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "prop",
+
+    range: [16, 20],
+    loc: {
+      start: { column: 2, line: 2 },
+      end: { column: 6, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 6, line: 2 },
+      end: { column: 7, line: 2 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [22, 23],
+    loc: {
+      start: { column: 0, line: 3 },
+      end: { column: 1, line: 3 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..8e0b58b2efe
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration with-member-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..32b0173342d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/fixtures/with-member-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,72 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSInterfaceDeclaration with-member-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'interface',
+
+      range: [0, 9],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 9, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'F',
+
+      range: [10, 11],
+      loc: {
+        start: { column: 10, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '{',
+
+      range: [12, 13],
+      loc: {
+        start: { column: 12, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'prop',
+
+      range: [16, 20],
+      loc: {
+        start: { column: 2, line: 2 },
+        end: { column: 6, line: 2 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ';',
+
+      range: [20, 21],
+      loc: {
+        start: { column: 6, line: 2 },
+        end: { column: 7, line: 2 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '}',
+
+      range: [22, 23],
+      loc: {
+        start: { column: 0, line: 3 },
+        end: { column: 1, line: 3 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/spec.ts b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/spec.ts
index 1e95380c3cb..a75c769daf9 100644
--- a/packages/ast-spec/src/declaration/TSInterfaceDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/TSInterfaceDeclaration/spec.ts
@@ -7,11 +7,30 @@ import type { TSTypeParameterDeclaration } from '../../special/TSTypeParameterDe
 
 export interface TSInterfaceDeclaration extends BaseNode {
   type: AST_NODE_TYPES.TSInterfaceDeclaration;
+  // TODO(#4759) - breaking change remove this
+  abstract?: boolean;
+  /**
+   * The body of the interface
+   */
   body: TSInterfaceBody;
-  id: Identifier;
-  typeParameters?: TSTypeParameterDeclaration;
+  /**
+   * Whether the interface was `declare`d, `undefined` otherwise
+   */
+  // TODO(#5020) - make this `false` if it is not `declare`d
+  declare?: boolean;
+  /**
+   * The types this interface `extends`
+   */
   extends?: TSInterfaceHeritage[];
+  /**
+   * The name of this interface
+   */
+  id: Identifier;
+  // TODO(#4759) - breaking change remove this
   implements?: TSInterfaceHeritage[];
-  abstract?: boolean;
-  declare?: boolean;
+  /**
+   * The generic type parameters declared for the interface.
+   * This is `undefined` if there are no generic type parameters declared.
+   */
+  typeParameters?: TSTypeParameterDeclaration;
 }
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/fixture.ts
new file mode 100644
index 00000000000..95cad257504
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/fixture.ts
@@ -0,0 +1 @@
+module 1 {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..082a7d854c2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ module-invalid-id TSESTree - Error 1`] = `[TSError: Namespace name cannot be '1'.]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..9848b6e55cd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ module-invalid-id Babel - Error 1`] = `[SyntaxError: Missing semicolon. (1:6)]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..1ed7cf1aba5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-invalid-id/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ module-invalid-id Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/fixture.ts
new file mode 100644
index 00000000000..7d0dcd8add3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/fixture.ts
@@ -0,0 +1 @@
+module F;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..0a8a833a27a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ module-missing-body TSESTree - Error 1`] = `[TSError: '{' expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..c7c0b7ca1d4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ module-missing-body Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:8)]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..f8381f6dde3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/module-missing-body/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ module-missing-body Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/fixture.ts
new file mode 100644
index 00000000000..fe124427907
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/fixture.ts
@@ -0,0 +1 @@
+declare namespace F;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..6a1c0b8eebf
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-declare-no-body TSESTree - Error 1`] = `[TSError: '{' expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..0cc4df30bc5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-declare-no-body Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:19)]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..62ff96dfe97
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-declare-no-body/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-declare-no-body Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/fixture.ts
new file mode 100644
index 00000000000..173024ac6a3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/fixture.ts
@@ -0,0 +1 @@
+namespace 'a' {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..bdb99cfb914
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-id-literal TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..3dc7480d32a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-id-literal Babel - Error 1`] = `[SyntaxError: Missing semicolon. (1:9)]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..354b7482759
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-id-literal/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-id-literal Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/fixture.ts
new file mode 100644
index 00000000000..32cdae5da4b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/fixture.ts
@@ -0,0 +1 @@
+namespace 1 {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..3fbcf961cfa
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-invalid-id TSESTree - Error 1`] = `[TSError: Namespace name cannot be '1'.]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..be52f2461a2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-invalid-id Babel - Error 1`] = `[SyntaxError: Missing semicolon. (1:9)]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..1a3abc42ed7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-invalid-id/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-invalid-id Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/fixture.ts
new file mode 100644
index 00000000000..d0caf4acec4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/fixture.ts
@@ -0,0 +1 @@
+namespace F;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..33a26d312ca
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-no-body TSESTree - Error 1`] = `[TSError: '{' expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..4e9e941de86
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-no-body Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:11)]`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..2c9165727c1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/_error_/namespace-no-body/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration _error_ namespace-no-body Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/fixture.ts
new file mode 100644
index 00000000000..3f1ee73dee1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/fixture.ts
@@ -0,0 +1 @@
+declare global {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..424909a0e10
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,47 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration global TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [15, 17],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 17, line: 1 },
+        },
+      },
+      declare: true,
+      global: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "global",
+
+        range: [8, 14],
+        loc: {
+          start: { column: 8, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..910131ba7b8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration global TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "global",
+
+    range: [8, 14],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..4e1a238040b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/3-Babel-AST.shot
@@ -0,0 +1,47 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration global Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [15, 17],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 17, line: 1 },
+        },
+      },
+      declare: true,
+      global: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "global",
+
+        range: [8, 14],
+        loc: {
+          start: { column: 8, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+
+      range: [0, 17],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 17, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 18],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..393012dfc4b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration global Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "global",
+
+    range: [8, 14],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..bdf25926153
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration global AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..b92eb152c95
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/global/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration global AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/fixture.ts
new file mode 100644
index 00000000000..2758941f3c3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/fixture.ts
@@ -0,0 +1 @@
+declare module 'a';
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..a0ad297f73c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,37 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare-no-body TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      declare: true,
+      id: Literal {
+        type: "Literal",
+        raw: "'a'",
+        value: "a",
+
+        range: [15, 18],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+
+      range: [0, 19],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 20],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..0c2959419e2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare-no-body TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [8, 14],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'a'",
+
+    range: [15, 18],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..d90a0fdea6a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/3-Babel-AST.shot
@@ -0,0 +1,37 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare-no-body Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      declare: true,
+      id: Literal {
+        type: "Literal",
+        raw: "'a'",
+        value: "a",
+
+        range: [15, 18],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+
+      range: [0, 19],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 20],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..d6f2b8430a1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare-no-body Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [8, 14],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'a'",
+
+    range: [15, 18],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..29dc0c7a776
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare-no-body AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..6341815959d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare-no-body/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare-no-body AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/fixture.ts
new file mode 100644
index 00000000000..2cbec48309b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/fixture.ts
@@ -0,0 +1 @@
+declare module F {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..74a329eeb58
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [17, 19],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [15, 16],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 16, line: 1 },
+        },
+      },
+
+      range: [0, 19],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 20],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..487f26037f8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [8, 14],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..dd00b5173a1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/3-Babel-AST.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [17, 19],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [15, 16],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 16, line: 1 },
+        },
+      },
+
+      range: [0, 19],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 20],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..e2dfc2330dc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [8, 14],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..d70930f793c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..bae19f0bd14
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-declare/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-declare AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/fixture.ts
new file mode 100644
index 00000000000..499f1194467
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/fixture.ts
@@ -0,0 +1 @@
+module F {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..3559c1ce1a1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,45 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-identifier TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [9, 11],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+
+      range: [0, 11],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 12],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..e8658090b43
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-identifier TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..7acb1bcd871
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/3-Babel-AST.shot
@@ -0,0 +1,45 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-identifier Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [9, 11],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+
+      range: [0, 11],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 12],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..f8093f686fb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-identifier Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..829de93e3df
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-identifier AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..2d09487a662
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-identifier/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-identifier AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/fixture.ts
new file mode 100644
index 00000000000..6e2ddacd253
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/fixture.ts
@@ -0,0 +1 @@
+module 'a' {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..da4f7cdc9af
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-literal TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [11, 13],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 13, line: 1 },
+        },
+      },
+      id: Literal {
+        type: "Literal",
+        raw: "'a'",
+        value: "a",
+
+        range: [7, 10],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 10, line: 1 },
+        },
+      },
+
+      range: [0, 13],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 14],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..35a1efd6dc9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-literal TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'a'",
+
+    range: [7, 10],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..fafc835ec47
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/3-Babel-AST.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-literal Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [11, 13],
+        loc: {
+          start: { column: 11, line: 1 },
+          end: { column: 13, line: 1 },
+        },
+      },
+      id: Literal {
+        type: "Literal",
+        raw: "'a'",
+        value: "a",
+
+        range: [7, 10],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 10, line: 1 },
+        },
+      },
+
+      range: [0, 13],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 14],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..a463f80b9e5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-literal Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  String {
+    type: "String",
+    value: "'a'",
+
+    range: [7, 10],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..f13f22dfe7d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-literal AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..1e1bc9d73c3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-literal/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-literal AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/fixture.ts
new file mode 100644
index 00000000000..56162d5e58b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/fixture.ts
@@ -0,0 +1 @@
+module A.B.C {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..3dfc069dda7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,83 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-qualified-name TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleDeclaration {
+        type: "TSModuleDeclaration",
+        body: TSModuleDeclaration {
+          type: "TSModuleDeclaration",
+          body: TSModuleBlock {
+            type: "TSModuleBlock",
+            body: Array [],
+
+            range: [13, 15],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 15, line: 1 },
+            },
+          },
+          id: Identifier {
+            type: "Identifier",
+            name: "C",
+
+            range: [11, 12],
+            loc: {
+              start: { column: 11, line: 1 },
+              end: { column: 12, line: 1 },
+            },
+          },
+
+          range: [11, 15],
+          loc: {
+            start: { column: 11, line: 1 },
+            end: { column: 15, line: 1 },
+          },
+        },
+        id: Identifier {
+          type: "Identifier",
+          name: "B",
+
+          range: [9, 10],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 10, line: 1 },
+          },
+        },
+
+        range: [9, 15],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 15, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "A",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+
+      range: [0, 15],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 15, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 16],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..70d7cd911e1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-qualified-name TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "B",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "C",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..c6af56a9883
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/3-Babel-AST.shot
@@ -0,0 +1,83 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-qualified-name Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleDeclaration {
+        type: "TSModuleDeclaration",
+        body: TSModuleDeclaration {
+          type: "TSModuleDeclaration",
+          body: TSModuleBlock {
+            type: "TSModuleBlock",
+            body: Array [],
+
+            range: [13, 15],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 15, line: 1 },
+            },
+          },
+          id: Identifier {
+            type: "Identifier",
+            name: "C",
+
+            range: [11, 12],
+            loc: {
+              start: { column: 11, line: 1 },
+              end: { column: 12, line: 1 },
+            },
+          },
+
+          range: [11, 15],
+          loc: {
+            start: { column: 11, line: 1 },
+            end: { column: 15, line: 1 },
+          },
+        },
+        id: Identifier {
+          type: "Identifier",
+          name: "B",
+
+          range: [9, 10],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 10, line: 1 },
+          },
+        },
+
+        range: [9, 15],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 15, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "A",
+
+        range: [7, 8],
+        loc: {
+          start: { column: 7, line: 1 },
+          end: { column: 8, line: 1 },
+        },
+      },
+
+      range: [0, 15],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 15, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 16],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..b03c2f7b5a8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-qualified-name Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "module",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "B",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "C",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..d442f261db2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-qualified-name AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..68241771f7c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/module-id-qualified-name/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration module-id-qualified-name AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/fixture.ts
new file mode 100644
index 00000000000..ebc35823e75
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/fixture.ts
@@ -0,0 +1 @@
+declare namespace F {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..c373a655222
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-declare TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [20, 22],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 22, line: 1 },
+        },
+      },
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [18, 19],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+
+      range: [0, 22],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 22, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 23],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..18d298125dd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-declare TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "namespace",
+
+    range: [8, 17],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..26936650860
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/3-Babel-AST.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-declare Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [20, 22],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 22, line: 1 },
+        },
+      },
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [18, 19],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+
+      range: [0, 22],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 22, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 23],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..374070330ed
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-declare Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "namespace",
+
+    range: [8, 17],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..614b9695a3c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-declare AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..1e9fda98a78
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-declare/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-declare AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/fixture.ts
new file mode 100644
index 00000000000..fb1741b05b2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/fixture.ts
@@ -0,0 +1 @@
+namespace F {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..e6303e2d3ed
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,45 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-identifier TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [12, 14],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 14],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 15],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..15cd21e3ad5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-identifier TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "namespace",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..2e47480e044
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/3-Babel-AST.shot
@@ -0,0 +1,45 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-identifier Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleBlock {
+        type: "TSModuleBlock",
+        body: Array [],
+
+        range: [12, 14],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "F",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 14],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 15],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..1fb07e00228
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-identifier Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "namespace",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "F",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..a0aa056256b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-identifier AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..112e01d377c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-identifier/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-identifier AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/fixture.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/fixture.ts
new file mode 100644
index 00000000000..c7c1b751f8d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/fixture.ts
@@ -0,0 +1 @@
+namespace A.B.C {}
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..98cd5bbe817
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,83 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-qualified-name TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleDeclaration {
+        type: "TSModuleDeclaration",
+        body: TSModuleDeclaration {
+          type: "TSModuleDeclaration",
+          body: TSModuleBlock {
+            type: "TSModuleBlock",
+            body: Array [],
+
+            range: [16, 18],
+            loc: {
+              start: { column: 16, line: 1 },
+              end: { column: 18, line: 1 },
+            },
+          },
+          id: Identifier {
+            type: "Identifier",
+            name: "C",
+
+            range: [14, 15],
+            loc: {
+              start: { column: 14, line: 1 },
+              end: { column: 15, line: 1 },
+            },
+          },
+
+          range: [14, 18],
+          loc: {
+            start: { column: 14, line: 1 },
+            end: { column: 18, line: 1 },
+          },
+        },
+        id: Identifier {
+          type: "Identifier",
+          name: "B",
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+
+        range: [12, 18],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "A",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 18],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 18, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 19],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..fcd5df00be8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-qualified-name TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "namespace",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "B",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "C",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..569b49fb327
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/3-Babel-AST.shot
@@ -0,0 +1,83 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-qualified-name Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSModuleDeclaration {
+      type: "TSModuleDeclaration",
+      body: TSModuleDeclaration {
+        type: "TSModuleDeclaration",
+        body: TSModuleDeclaration {
+          type: "TSModuleDeclaration",
+          body: TSModuleBlock {
+            type: "TSModuleBlock",
+            body: Array [],
+
+            range: [16, 18],
+            loc: {
+              start: { column: 16, line: 1 },
+              end: { column: 18, line: 1 },
+            },
+          },
+          id: Identifier {
+            type: "Identifier",
+            name: "C",
+
+            range: [14, 15],
+            loc: {
+              start: { column: 14, line: 1 },
+              end: { column: 15, line: 1 },
+            },
+          },
+
+          range: [14, 18],
+          loc: {
+            start: { column: 14, line: 1 },
+            end: { column: 18, line: 1 },
+          },
+        },
+        id: Identifier {
+          type: "Identifier",
+          name: "B",
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+
+        range: [12, 18],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "A",
+
+        range: [10, 11],
+        loc: {
+          start: { column: 10, line: 1 },
+          end: { column: 11, line: 1 },
+        },
+      },
+
+      range: [0, 18],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 18, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 19],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..8f3b974a3ab
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-qualified-name Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "namespace",
+
+    range: [0, 9],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "A",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "B",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ".",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "C",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..a7a16eee58a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-qualified-name AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..1e60c8843aa
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/fixtures/namespace-id-qualified-name/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSModuleDeclaration namespace-id-qualified-name AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSModuleDeclaration/spec.ts b/packages/ast-spec/src/declaration/TSModuleDeclaration/spec.ts
index ac63e52a593..e077d1648e1 100644
--- a/packages/ast-spec/src/declaration/TSModuleDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/TSModuleDeclaration/spec.ts
@@ -7,11 +7,24 @@ import type { Modifier } from '../../unions/Modifier';
 
 export interface TSModuleDeclaration extends BaseNode {
   type: AST_NODE_TYPES.TSModuleDeclaration;
+  /**
+   * The name of the module
+   * ```
+   * namespace A {}
+   * namespace A.B.C {}
+   * module 'a' {}
+   * ```
+   */
   id: Identifier | Literal;
+  /**
+   * The body of the module.
+   * This can only be `undefined` for the code `declare module 'mod';`
+   * This will be a `TSModuleDeclaration` if the name is "nested" (`Foo.Bar`).
+   */
   body?:
     | TSModuleBlock
     /*
-    TODO - we currently emit this due to bad parser handling of nested modules
+    TODO(#4966) - we currently emit this due to bad parser handling of nested modules
     namespace Foo.Bar {}
     ^^^^^^^^^^^^^^^^^^^^ TSModuleDeclaration
                   ^^^^^^ TSModuleDeclaration
@@ -20,7 +33,22 @@ export interface TSModuleDeclaration extends BaseNode {
     This should instead emit a TSQualifiedName for the `id` and not emit an inner TSModuleDeclaration
     */
     | TSModuleDeclaration;
+  /**
+   * Whether this is a global declaration
+   * ```
+   * declare global {}
+   * ```
+   */
+  // TODO(#5020) - make this `false` if not `global`
   global?: boolean;
+  /**
+   * Whether the module is `declare`d
+   * ```
+   * declare namespace F {}
+   * ```
+   */
+  // TODO(#5020) - make this `false` if it is not `declare`d
   declare?: boolean;
+  // TODO(#4759) - breaking change remove this
   modifiers?: Modifier[];
 }
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/fixture.ts b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/fixture.ts
new file mode 100644
index 00000000000..bbcfe5795de
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/fixture.ts
@@ -0,0 +1 @@
+export as namespace;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..e47c9aa7c25
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration _error_ missing-id TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..300850581d6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration _error_ missing-id Babel - Error 1`] = `[SyntaxError: Unexpected token (1:19)]`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..0b5d774603f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/missing-id/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration _error_ missing-id Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/fixture.ts b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
new file mode 100644
index 00000000000..a8878e61afe
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
@@ -0,0 +1 @@
+export as namespace 1;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..3e11b470029
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration _error_ non-identifier-name TSESTree - Error 1`] = `[TSError: Identifier expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..f2641cc64de
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration _error_ non-identifier-name Babel - Error 1`] = `[SyntaxError: Unexpected token (1:20)]`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..defe8a17bba
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration _error_ non-identifier-name Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/fixture.ts b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/fixture.ts
new file mode 100644
index 00000000000..ff8bbadf397
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/fixture.ts
@@ -0,0 +1 @@
+export as namespace a;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..914df1fad85
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,35 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration valid TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSNamespaceExportDeclaration {
+      type: "TSNamespaceExportDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "a",
+
+        range: [20, 21],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 21, line: 1 },
+        },
+      },
+
+      range: [0, 22],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 22, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 23],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..8399bbd3d1d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration valid TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "export",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "as",
+
+    range: [7, 9],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "namespace",
+
+    range: [10, 19],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..c3861bcab7b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/3-Babel-AST.shot
@@ -0,0 +1,35 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration valid Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSNamespaceExportDeclaration {
+      type: "TSNamespaceExportDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "a",
+
+        range: [20, 21],
+        loc: {
+          start: { column: 20, line: 1 },
+          end: { column: 21, line: 1 },
+        },
+      },
+
+      range: [0, 22],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 22, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 23],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..dfe3eae2d2a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration valid Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "export",
+
+    range: [0, 6],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "as",
+
+    range: [7, 9],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "namespace",
+
+    range: [10, 19],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "a",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [21, 22],
+    loc: {
+      start: { column: 21, line: 1 },
+      end: { column: 22, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..6cd11e1f4b3
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration valid AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..c7d4f1d7315
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/fixtures/valid/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSNamespaceExportDeclaration valid AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/spec.ts b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/spec.ts
index 6853d4a2854..da63cca2ac6 100644
--- a/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/TSNamespaceExportDeclaration/spec.ts
@@ -4,5 +4,8 @@ import type { Identifier } from '../../expression/Identifier/spec';
 
 export interface TSNamespaceExportDeclaration extends BaseNode {
   type: AST_NODE_TYPES.TSNamespaceExportDeclaration;
+  /**
+   * The name the global variable being exported to
+   */
   id: Identifier;
 }
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/fixture.ts b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/fixture.ts
new file mode 100644
index 00000000000..3bd6bc6c605
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/fixture.ts
@@ -0,0 +1 @@
+type T<> = 1;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..9902528eb41
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration _error_ missing-type-parameter TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..b18ec532458
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration _error_ missing-type-parameter Babel - Error 1`] = `[SyntaxError: Type parameter list cannot be empty. (1:6)]`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..99587163b89
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration _error_ missing-type-parameter Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/fixture.ts b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
new file mode 100644
index 00000000000..533f0b183cf
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/fixture.ts
@@ -0,0 +1 @@
+type 1 = 2;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..7eaf3f0bba4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration _error_ non-identifier-name TSESTree - Error 1`] = `[TSError: Type alias name cannot be '1'.]`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..f7c419205f7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration _error_ non-identifier-name Babel - Error 1`] = `[SyntaxError: Missing semicolon. (1:4)]`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..7ccef6da61f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration _error_ non-identifier-name Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/fixture.ts b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/fixture.ts
new file mode 100644
index 00000000000..059c8eaf43d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/fixture.ts
@@ -0,0 +1 @@
+type T<1> = 2;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..b11bc95c96d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration _error_ non-identifier-type-parameter TSESTree - Error 1`] = `[TSError: Type parameter declaration expected.]`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..bb7b44f3afe
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration _error_ non-identifier-type-parameter Babel - Error 1`] = `[SyntaxError: Unexpected token (1:7)]`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..ad412071cc1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/_error_/non-identifier-type-parameter/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration _error_ non-identifier-type-parameter Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/fixture.ts b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/fixture.ts
new file mode 100644
index 00000000000..87882321e28
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/fixture.ts
@@ -0,0 +1 @@
+declare type T = 1;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..63becdaa218
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration declare TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSTypeAliasDeclaration {
+      type: "TSTypeAliasDeclaration",
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "T",
+
+        range: [13, 14],
+        loc: {
+          start: { column: 13, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+      typeAnnotation: TSLiteralType {
+        type: "TSLiteralType",
+        literal: Literal {
+          type: "Literal",
+          raw: "1",
+          value: 1,
+
+          range: [17, 18],
+          loc: {
+            start: { column: 17, line: 1 },
+            end: { column: 18, line: 1 },
+          },
+        },
+
+        range: [17, 18],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+
+      range: [0, 19],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 20],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..8599ab30609
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration declare TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [8, 12],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..36939724fc4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration declare Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSTypeAliasDeclaration {
+      type: "TSTypeAliasDeclaration",
+      declare: true,
+      id: Identifier {
+        type: "Identifier",
+        name: "T",
+
+        range: [13, 14],
+        loc: {
+          start: { column: 13, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+      typeAnnotation: TSLiteralType {
+        type: "TSLiteralType",
+        literal: Literal {
+          type: "Literal",
+          raw: "1",
+          value: 1,
+
+          range: [17, 18],
+          loc: {
+            start: { column: 17, line: 1 },
+            end: { column: 18, line: 1 },
+          },
+        },
+
+        range: [17, 18],
+        loc: {
+          start: { column: 17, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+
+      range: [0, 19],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 19, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 20],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..48da9f1cfb8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,66 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration declare Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [8, 12],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [15, 16],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 16, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [17, 18],
+    loc: {
+      start: { column: 17, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..890509a8dcb
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration declare AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..6d9b60683b6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration declare AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/fixture.ts b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/fixture.ts
new file mode 100644
index 00000000000..98fb2f852da
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/fixture.ts
@@ -0,0 +1 @@
+type T<U> = 1;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..af8a41ed478
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,87 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-many TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSTypeAliasDeclaration {
+      type: "TSTypeAliasDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "T",
+
+        range: [5, 6],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 6, line: 1 },
+        },
+      },
+      typeAnnotation: TSLiteralType {
+        type: "TSLiteralType",
+        literal: Literal {
+          type: "Literal",
+          raw: "1",
+          value: 1,
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+
+        range: [12, 13],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 13, line: 1 },
+        },
+      },
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "U",
+
+              range: [7, 8],
+              loc: {
+                start: { column: 7, line: 1 },
+                end: { column: 8, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+        ],
+
+        range: [6, 9],
+        loc: {
+          start: { column: 6, line: 1 },
+          end: { column: 9, line: 1 },
+        },
+      },
+
+      range: [0, 14],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 15],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..a84e1cc058d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-many TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..db6209388e7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/3-Babel-AST.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-many Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSTypeAliasDeclaration {
+      type: "TSTypeAliasDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "T",
+
+        range: [5, 6],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 6, line: 1 },
+        },
+      },
+      typeAnnotation: TSLiteralType {
+        type: "TSLiteralType",
+        literal: Literal {
+          type: "Literal",
+          raw: "1",
+          value: 1,
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+
+        range: [12, 13],
+        loc: {
+          start: { column: 12, line: 1 },
+          end: { column: 13, line: 1 },
+        },
+      },
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "U",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+        ],
+
+        range: [6, 9],
+        loc: {
+          start: { column: 6, line: 1 },
+          end: { column: 9, line: 1 },
+        },
+      },
+
+      range: [0, 14],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 15],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..92442f10c0d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,86 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-many Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..a80b5aa0a11
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,92 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-many AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      TSTypeAliasDeclaration {
+        type: 'TSTypeAliasDeclaration',
+        id: Identifier {
+          type: 'Identifier',
+          name: 'T',
+
+          range: [5, 6],
+          loc: {
+            start: { column: 5, line: 1 },
+            end: { column: 6, line: 1 },
+          },
+        },
+        typeAnnotation: TSLiteralType {
+          type: 'TSLiteralType',
+          literal: Literal {
+            type: 'Literal',
+            raw: '1',
+            value: 1,
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+        typeParameters: TSTypeParameterDeclaration {
+          type: 'TSTypeParameterDeclaration',
+          params: Array [
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'U',
+-
+-               range: [7, 8],
+-               loc: {
+-                 start: { column: 7, line: 1 },
+-                 end: { column: 8, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'U',
+
+              range: [7, 8],
+              loc: {
+                start: { column: 7, line: 1 },
+                end: { column: 8, line: 1 },
+              },
+            },
+          ],
+
+          range: [6, 9],
+          loc: {
+            start: { column: 6, line: 1 },
+            end: { column: 9, line: 1 },
+          },
+        },
+
+        range: [0, 14],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 14, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 15],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..b693d3c055d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-many/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-many AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/fixture.ts b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/fixture.ts
new file mode 100644
index 00000000000..8ca0a977313
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/fixture.ts
@@ -0,0 +1 @@
+type T<U, V, W> = 1;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..6bf2120e61b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,129 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-one TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSTypeAliasDeclaration {
+      type: "TSTypeAliasDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "T",
+
+        range: [5, 6],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 6, line: 1 },
+        },
+      },
+      typeAnnotation: TSLiteralType {
+        type: "TSLiteralType",
+        literal: Literal {
+          type: "Literal",
+          raw: "1",
+          value: 1,
+
+          range: [18, 19],
+          loc: {
+            start: { column: 18, line: 1 },
+            end: { column: 19, line: 1 },
+          },
+        },
+
+        range: [18, 19],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "U",
+
+              range: [7, 8],
+              loc: {
+                start: { column: 7, line: 1 },
+                end: { column: 8, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "V",
+
+              range: [10, 11],
+              loc: {
+                start: { column: 10, line: 1 },
+                end: { column: 11, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [10, 11],
+            loc: {
+              start: { column: 10, line: 1 },
+              end: { column: 11, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            in: false,
+            name: Identifier {
+              type: "Identifier",
+              name: "W",
+
+              range: [13, 14],
+              loc: {
+                start: { column: 13, line: 1 },
+                end: { column: 14, line: 1 },
+              },
+            },
+            out: false,
+
+            range: [13, 14],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 14, line: 1 },
+            },
+          },
+        ],
+
+        range: [6, 15],
+        loc: {
+          start: { column: 6, line: 1 },
+          end: { column: 15, line: 1 },
+        },
+      },
+
+      range: [0, 20],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 20, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 21],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..c23889fa8fd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,126 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-one TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "V",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "W",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..60c8977e60f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/3-Babel-AST.shot
@@ -0,0 +1,96 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-one Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSTypeAliasDeclaration {
+      type: "TSTypeAliasDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "T",
+
+        range: [5, 6],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 6, line: 1 },
+        },
+      },
+      typeAnnotation: TSLiteralType {
+        type: "TSLiteralType",
+        literal: Literal {
+          type: "Literal",
+          raw: "1",
+          value: 1,
+
+          range: [18, 19],
+          loc: {
+            start: { column: 18, line: 1 },
+            end: { column: 19, line: 1 },
+          },
+        },
+
+        range: [18, 19],
+        loc: {
+          start: { column: 18, line: 1 },
+          end: { column: 19, line: 1 },
+        },
+      },
+      typeParameters: TSTypeParameterDeclaration {
+        type: "TSTypeParameterDeclaration",
+        params: Array [
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "U",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "V",
+
+            range: [10, 11],
+            loc: {
+              start: { column: 10, line: 1 },
+              end: { column: 11, line: 1 },
+            },
+          },
+          TSTypeParameter {
+            type: "TSTypeParameter",
+            name: "W",
+
+            range: [13, 14],
+            loc: {
+              start: { column: 13, line: 1 },
+              end: { column: 14, line: 1 },
+            },
+          },
+        ],
+
+        range: [6, 15],
+        loc: {
+          start: { column: 6, line: 1 },
+          end: { column: 15, line: 1 },
+        },
+      },
+
+      range: [0, 20],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 20, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 21],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..f6e56c2aa5f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,126 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-one Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "<",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "U",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "V",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "W",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ">",
+
+    range: [14, 15],
+    loc: {
+      start: { column: 14, line: 1 },
+      end: { column: 15, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [16, 17],
+    loc: {
+      start: { column: 16, line: 1 },
+      end: { column: 17, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [18, 19],
+    loc: {
+      start: { column: 18, line: 1 },
+      end: { column: 19, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..d754f2bf397
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,136 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-one AST Alignment - AST 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Program {
+    type: 'Program',
+    body: Array [
+      TSTypeAliasDeclaration {
+        type: 'TSTypeAliasDeclaration',
+        id: Identifier {
+          type: 'Identifier',
+          name: 'T',
+
+          range: [5, 6],
+          loc: {
+            start: { column: 5, line: 1 },
+            end: { column: 6, line: 1 },
+          },
+        },
+        typeAnnotation: TSLiteralType {
+          type: 'TSLiteralType',
+          literal: Literal {
+            type: 'Literal',
+            raw: '1',
+            value: 1,
+
+            range: [18, 19],
+            loc: {
+              start: { column: 18, line: 1 },
+              end: { column: 19, line: 1 },
+            },
+          },
+
+          range: [18, 19],
+          loc: {
+            start: { column: 18, line: 1 },
+            end: { column: 19, line: 1 },
+          },
+        },
+        typeParameters: TSTypeParameterDeclaration {
+          type: 'TSTypeParameterDeclaration',
+          params: Array [
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'U',
+-
+-               range: [7, 8],
+-               loc: {
+-                 start: { column: 7, line: 1 },
+-                 end: { column: 8, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'U',
+
+              range: [7, 8],
+              loc: {
+                start: { column: 7, line: 1 },
+                end: { column: 8, line: 1 },
+              },
+            },
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'V',
+-
+-               range: [10, 11],
+-               loc: {
+-                 start: { column: 10, line: 1 },
+-                 end: { column: 11, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'V',
+
+              range: [10, 11],
+              loc: {
+                start: { column: 10, line: 1 },
+                end: { column: 11, line: 1 },
+              },
+            },
+            TSTypeParameter {
+              type: 'TSTypeParameter',
+-             in: false,
+-             name: Identifier {
+-               type: 'Identifier',
+-               name: 'W',
+-
+-               range: [13, 14],
+-               loc: {
+-                 start: { column: 13, line: 1 },
+-                 end: { column: 14, line: 1 },
+-               },
+-             },
+-             out: false,
++             name: 'W',
+
+              range: [13, 14],
+              loc: {
+                start: { column: 13, line: 1 },
+                end: { column: 14, line: 1 },
+              },
+            },
+          ],
+
+          range: [6, 15],
+          loc: {
+            start: { column: 6, line: 1 },
+            end: { column: 15, line: 1 },
+          },
+        },
+
+        range: [0, 20],
+        loc: {
+          start: { column: 0, line: 1 },
+          end: { column: 20, line: 1 },
+        },
+      },
+    ],
+    sourceType: 'script',
+
+    range: [0, 21],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 0, line: 2 },
+    },
+  }"
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..bc7fa2d6aac
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/type-param-one/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration type-param-one AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/fixture.ts b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/fixture.ts
new file mode 100644
index 00000000000..0d6d62642cc
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/fixture.ts
@@ -0,0 +1 @@
+type T = 1;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..424ed29eb52
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,55 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration valid TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSTypeAliasDeclaration {
+      type: "TSTypeAliasDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "T",
+
+        range: [5, 6],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 6, line: 1 },
+        },
+      },
+      typeAnnotation: TSLiteralType {
+        type: "TSLiteralType",
+        literal: Literal {
+          type: "Literal",
+          raw: "1",
+          value: 1,
+
+          range: [9, 10],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 10, line: 1 },
+          },
+        },
+
+        range: [9, 10],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 10, line: 1 },
+        },
+      },
+
+      range: [0, 11],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 12],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..e3b35e444aa
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration valid TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..7fad93c1cab
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/3-Babel-AST.shot
@@ -0,0 +1,55 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration valid Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    TSTypeAliasDeclaration {
+      type: "TSTypeAliasDeclaration",
+      id: Identifier {
+        type: "Identifier",
+        name: "T",
+
+        range: [5, 6],
+        loc: {
+          start: { column: 5, line: 1 },
+          end: { column: 6, line: 1 },
+        },
+      },
+      typeAnnotation: TSLiteralType {
+        type: "TSLiteralType",
+        literal: Literal {
+          type: "Literal",
+          raw: "1",
+          value: 1,
+
+          range: [9, 10],
+          loc: {
+            start: { column: 9, line: 1 },
+            end: { column: 10, line: 1 },
+          },
+        },
+
+        range: [9, 10],
+        loc: {
+          start: { column: 9, line: 1 },
+          end: { column: 10, line: 1 },
+        },
+      },
+
+      range: [0, 11],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 12],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..12901c93f94
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration valid Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "type",
+
+    range: [0, 4],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 4, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "T",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..9cc16a451ec
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration valid AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..4de04778d63
--- /dev/null
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/fixtures/valid/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration TSTypeAliasDeclaration valid AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/spec.ts b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/spec.ts
index 61ce986c2a2..15ab0a40c13 100644
--- a/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/TSTypeAliasDeclaration/spec.ts
@@ -6,8 +6,25 @@ import type { TypeNode } from '../../unions/TypeNode';
 
 export interface TSTypeAliasDeclaration extends BaseNode {
   type: AST_NODE_TYPES.TSTypeAliasDeclaration;
+  /**
+   * Whether the type was `declare`d.
+   * ```
+   * declare type T = 1;
+   * ```
+   */
+  // TODO(#5020) - make this `false` if it is not `declare`d
+  declare?: boolean;
+  /**
+   * The name of the type.
+   */
   id: Identifier;
+  /**
+   * The "value" (type) of the declaration
+   */
   typeAnnotation: TypeNode;
-  declare?: boolean;
+  /**
+   * The generic type parameters declared for the type.
+   * This is `undefined` if there are no generic type parameters declared.
+   */
   typeParameters?: TSTypeParameterDeclaration;
 }
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/fixture.ts
new file mode 100644
index 00000000000..21a6e1beba9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/fixture.ts
@@ -0,0 +1 @@
+const = 1;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..3f61a7ec4bd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration _error_ missing-id-with-value TSESTree - Error 1`] = `[TSError: Variable declaration expected.]`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..5e6f7bc3288
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration _error_ missing-id-with-value Babel - Error 1`] = `[SyntaxError: Unexpected token (1:6)]`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..830f2f4e93c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-with-value/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration _error_ missing-id-with-value Error Alignment 1`] = `"Both errored"`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/fixture.ts
new file mode 100644
index 00000000000..c53e6c27952
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/fixture.ts
@@ -0,0 +1 @@
+const;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/snapshots/1-TSESTree-Error.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/snapshots/1-TSESTree-Error.shot
new file mode 100644
index 00000000000..6537d529262
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/snapshots/1-TSESTree-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration _error_ missing-id-without-value TSESTree - Error 1`] = `"NO ERROR"`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/snapshots/2-Babel-Error.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/snapshots/2-Babel-Error.shot
new file mode 100644
index 00000000000..7a42d0e079b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/snapshots/2-Babel-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration _error_ missing-id-without-value Babel - Error 1`] = `[SyntaxError: Unexpected token (1:5)]`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/snapshots/3-Alignment-Error.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/snapshots/3-Alignment-Error.shot
new file mode 100644
index 00000000000..cd2401b6862
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/snapshots/3-Alignment-Error.shot
@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration _error_ missing-id-without-value Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/fixture.ts
new file mode 100644
index 00000000000..943c458c79e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/fixture.ts
@@ -0,0 +1 @@
+const x = 1;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..d7290bd926d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-with-value TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [6, 7],
+            loc: {
+              start: { column: 6, line: 1 },
+              end: { column: 7, line: 1 },
+            },
+          },
+          init: Literal {
+            type: "Literal",
+            raw: "1",
+            value: 1,
+
+            range: [10, 11],
+            loc: {
+              start: { column: 10, line: 1 },
+              end: { column: 11, line: 1 },
+            },
+          },
+
+          range: [6, 11],
+          loc: {
+            start: { column: 6, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+      ],
+      kind: "const",
+
+      range: [0, 12],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 13],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..df6fc4d3998
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-with-value TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "const",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..2cd36dbb467
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/3-Babel-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-with-value Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [6, 7],
+            loc: {
+              start: { column: 6, line: 1 },
+              end: { column: 7, line: 1 },
+            },
+          },
+          init: Literal {
+            type: "Literal",
+            raw: "1",
+            value: 1,
+
+            range: [10, 11],
+            loc: {
+              start: { column: 10, line: 1 },
+              end: { column: 11, line: 1 },
+            },
+          },
+
+          range: [6, 11],
+          loc: {
+            start: { column: 6, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+      ],
+      kind: "const",
+
+      range: [0, 12],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 13],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..5a5ce6855a2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-with-value Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "const",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..65c9ece0d43
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-with-value AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..abc02d7344b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-with-value/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-with-value AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/fixture.ts
new file mode 100644
index 00000000000..943c458c79e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/fixture.ts
@@ -0,0 +1 @@
+const x = 1;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..ac4cd6b70d8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-without-value TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [6, 7],
+            loc: {
+              start: { column: 6, line: 1 },
+              end: { column: 7, line: 1 },
+            },
+          },
+          init: Literal {
+            type: "Literal",
+            raw: "1",
+            value: 1,
+
+            range: [10, 11],
+            loc: {
+              start: { column: 10, line: 1 },
+              end: { column: 11, line: 1 },
+            },
+          },
+
+          range: [6, 11],
+          loc: {
+            start: { column: 6, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+      ],
+      kind: "const",
+
+      range: [0, 12],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 13],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..ee275ed63d9
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-without-value TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "const",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..c41b8219393
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/3-Babel-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-without-value Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [6, 7],
+            loc: {
+              start: { column: 6, line: 1 },
+              end: { column: 7, line: 1 },
+            },
+          },
+          init: Literal {
+            type: "Literal",
+            raw: "1",
+            value: 1,
+
+            range: [10, 11],
+            loc: {
+              start: { column: 10, line: 1 },
+              end: { column: 11, line: 1 },
+            },
+          },
+
+          range: [6, 11],
+          loc: {
+            start: { column: 6, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+      ],
+      kind: "const",
+
+      range: [0, 12],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 13],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..62b0896e9fd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-without-value Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "const",
+
+    range: [0, 5],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..56007597c38
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-without-value AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..cc37accf3c5
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/const-without-value/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration const-without-value AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/fixture.ts
new file mode 100644
index 00000000000..3dc63502e9c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/fixture.ts
@@ -0,0 +1 @@
+declare let x;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..19c59fcc338
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,49 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration declare TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+      ],
+      declare: true,
+      kind: "let",
+
+      range: [0, 14],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 15],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..5e3638b00d8
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration declare TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "let",
+
+    range: [8, 11],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..9cd49f740e4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/3-Babel-AST.shot
@@ -0,0 +1,49 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration declare Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [12, 13],
+            loc: {
+              start: { column: 12, line: 1 },
+              end: { column: 13, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [12, 13],
+          loc: {
+            start: { column: 12, line: 1 },
+            end: { column: 13, line: 1 },
+          },
+        },
+      ],
+      declare: true,
+      kind: "let",
+
+      range: [0, 14],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 15],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..5b7e380551c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,46 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration declare Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "declare",
+
+    range: [0, 7],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "let",
+
+    range: [8, 11],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [12, 13],
+    loc: {
+      start: { column: 12, line: 1 },
+      end: { column: 13, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [13, 14],
+    loc: {
+      start: { column: 13, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..005dc078e1d
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration declare AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..6d4eee5276a
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/declare/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,52 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration declare AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+    Identifier {
+      type: 'Identifier',
+      value: 'declare',
+
+      range: [0, 7],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 7, line: 1 },
+      },
+    },
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'let',
+
+      range: [8, 11],
+      loc: {
+        start: { column: 8, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'x',
+
+      range: [12, 13],
+      loc: {
+        start: { column: 12, line: 1 },
+        end: { column: 13, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ';',
+
+      range: [13, 14],
+      loc: {
+        start: { column: 13, line: 1 },
+        end: { column: 14, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/fixture.ts
new file mode 100644
index 00000000000..db913399448
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/fixture.ts
@@ -0,0 +1 @@
+let x = 1;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..a1c7625b457
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-with-value TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: Literal {
+            type: "Literal",
+            raw: "1",
+            value: 1,
+
+            range: [8, 9],
+            loc: {
+              start: { column: 8, line: 1 },
+              end: { column: 9, line: 1 },
+            },
+          },
+
+          range: [4, 9],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 9, line: 1 },
+          },
+        },
+      ],
+      kind: "let",
+
+      range: [0, 10],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 10, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 11],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..fa835fcdd32
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-with-value TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "let",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..5c5236d0482
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/3-Babel-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-with-value Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: Literal {
+            type: "Literal",
+            raw: "1",
+            value: 1,
+
+            range: [8, 9],
+            loc: {
+              start: { column: 8, line: 1 },
+              end: { column: 9, line: 1 },
+            },
+          },
+
+          range: [4, 9],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 9, line: 1 },
+          },
+        },
+      ],
+      kind: "let",
+
+      range: [0, 10],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 10, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 11],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..6f4bc74a6bd
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-with-value Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "let",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..2697799a415
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-with-value AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..e8e2c1727b2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-with-value/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,62 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-with-value AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'let',
+
+      range: [0, 3],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 3, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'x',
+
+      range: [4, 5],
+      loc: {
+        start: { column: 4, line: 1 },
+        end: { column: 5, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: '=',
+
+      range: [6, 7],
+      loc: {
+        start: { column: 6, line: 1 },
+        end: { column: 7, line: 1 },
+      },
+    },
+    Numeric {
+      type: 'Numeric',
+      value: '1',
+
+      range: [8, 9],
+      loc: {
+        start: { column: 8, line: 1 },
+        end: { column: 9, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ';',
+
+      range: [9, 10],
+      loc: {
+        start: { column: 9, line: 1 },
+        end: { column: 10, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/fixture.ts
new file mode 100644
index 00000000000..2756c24c457
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/fixture.ts
@@ -0,0 +1 @@
+let x;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..86d5e5fb9d1
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,48 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-without-value TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [4, 5],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 5, line: 1 },
+          },
+        },
+      ],
+      kind: "let",
+
+      range: [0, 6],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 6, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 7],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..66e4c76e567
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,36 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-without-value TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "let",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..78ac80c4cf4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/3-Babel-AST.shot
@@ -0,0 +1,48 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-without-value Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [4, 5],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 5, line: 1 },
+          },
+        },
+      ],
+      kind: "let",
+
+      range: [0, 6],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 6, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 7],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..78f58826ca6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,36 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-without-value Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "let",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..8082a31f808
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-without-value AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..949c66669c7
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/let-without-value/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,42 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration let-without-value AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'let',
+
+      range: [0, 3],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 3, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'x',
+
+      range: [4, 5],
+      loc: {
+        start: { column: 4, line: 1 },
+        end: { column: 5, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ';',
+
+      range: [5, 6],
+      loc: {
+        start: { column: 5, line: 1 },
+        end: { column: 6, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/fixture.ts
new file mode 100644
index 00000000000..6736426d70f
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/fixture.ts
@@ -0,0 +1 @@
+let x, y, z;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..f34767c5d50
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,88 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration multiple-declarations TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [4, 5],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 5, line: 1 },
+          },
+        },
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "y",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "z",
+
+            range: [10, 11],
+            loc: {
+              start: { column: 10, line: 1 },
+              end: { column: 11, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [10, 11],
+          loc: {
+            start: { column: 10, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+      ],
+      kind: "let",
+
+      range: [0, 12],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 13],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..b47b272ca68
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration multiple-declarations TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "let",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "y",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "z",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..b52ef758247
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/3-Babel-AST.shot
@@ -0,0 +1,88 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration multiple-declarations Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [4, 5],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 5, line: 1 },
+          },
+        },
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "y",
+
+            range: [7, 8],
+            loc: {
+              start: { column: 7, line: 1 },
+              end: { column: 8, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [7, 8],
+          loc: {
+            start: { column: 7, line: 1 },
+            end: { column: 8, line: 1 },
+          },
+        },
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "z",
+
+            range: [10, 11],
+            loc: {
+              start: { column: 10, line: 1 },
+              end: { column: 11, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [10, 11],
+          loc: {
+            start: { column: 10, line: 1 },
+            end: { column: 11, line: 1 },
+          },
+        },
+      ],
+      kind: "let",
+
+      range: [0, 12],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 13],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..2e324512abe
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,76 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration multiple-declarations Babel - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "let",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "y",
+
+    range: [7, 8],
+    loc: {
+      start: { column: 7, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ",",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "z",
+
+    range: [10, 11],
+    loc: {
+      start: { column: 10, line: 1 },
+      end: { column: 11, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [11, 12],
+    loc: {
+      start: { column: 11, line: 1 },
+      end: { column: 12, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..10b9167907c
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration multiple-declarations AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..d1e4b8c9a7b
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/multiple-declarations/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,82 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration multiple-declarations AST Alignment - Token 1`] = `
+"Snapshot Diff:
+- TSESTree
++ Babel
+
+  Array [
+-   Keyword {
+-     type: 'Keyword',
++   Identifier {
++     type: 'Identifier',
+      value: 'let',
+
+      range: [0, 3],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 3, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'x',
+
+      range: [4, 5],
+      loc: {
+        start: { column: 4, line: 1 },
+        end: { column: 5, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ',',
+
+      range: [5, 6],
+      loc: {
+        start: { column: 5, line: 1 },
+        end: { column: 6, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'y',
+
+      range: [7, 8],
+      loc: {
+        start: { column: 7, line: 1 },
+        end: { column: 8, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ',',
+
+      range: [8, 9],
+      loc: {
+        start: { column: 8, line: 1 },
+        end: { column: 9, line: 1 },
+      },
+    },
+    Identifier {
+      type: 'Identifier',
+      value: 'z',
+
+      range: [10, 11],
+      loc: {
+        start: { column: 10, line: 1 },
+        end: { column: 11, line: 1 },
+      },
+    },
+    Punctuator {
+      type: 'Punctuator',
+      value: ';',
+
+      range: [11, 12],
+      loc: {
+        start: { column: 11, line: 1 },
+        end: { column: 12, line: 1 },
+      },
+    },
+  ]"
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/fixture.ts
new file mode 100644
index 00000000000..b506100a909
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/fixture.ts
@@ -0,0 +1 @@
+var x = 1;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..d0b455dc1a2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-with-value TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: Literal {
+            type: "Literal",
+            raw: "1",
+            value: 1,
+
+            range: [8, 9],
+            loc: {
+              start: { column: 8, line: 1 },
+              end: { column: 9, line: 1 },
+            },
+          },
+
+          range: [4, 9],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 9, line: 1 },
+          },
+        },
+      ],
+      kind: "var",
+
+      range: [0, 10],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 10, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 11],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..2f9b9d78704
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-with-value TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "var",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..1420d42a8ca
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/3-Babel-AST.shot
@@ -0,0 +1,58 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-with-value Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: Literal {
+            type: "Literal",
+            raw: "1",
+            value: 1,
+
+            range: [8, 9],
+            loc: {
+              start: { column: 8, line: 1 },
+              end: { column: 9, line: 1 },
+            },
+          },
+
+          range: [4, 9],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 9, line: 1 },
+          },
+        },
+      ],
+      kind: "var",
+
+      range: [0, 10],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 10, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 11],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..bbab28532c6
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-with-value Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "var",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "=",
+
+    range: [6, 7],
+    loc: {
+      start: { column: 6, line: 1 },
+      end: { column: 7, line: 1 },
+    },
+  },
+  Numeric {
+    type: "Numeric",
+    value: "1",
+
+    range: [8, 9],
+    loc: {
+      start: { column: 8, line: 1 },
+      end: { column: 9, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [9, 10],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 10, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..b107c9499d4
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-with-value AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..1eb3bcd0b98
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-with-value/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-with-value AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/fixture.ts b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/fixture.ts
new file mode 100644
index 00000000000..96f6d3a3f15
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/fixture.ts
@@ -0,0 +1 @@
+var x;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/1-TSESTree-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/1-TSESTree-AST.shot
new file mode 100644
index 00000000000..9af840c2c53
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/1-TSESTree-AST.shot
@@ -0,0 +1,48 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-without-value TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [4, 5],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 5, line: 1 },
+          },
+        },
+      ],
+      kind: "var",
+
+      range: [0, 6],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 6, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 7],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/2-TSESTree-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/2-TSESTree-Tokens.shot
new file mode 100644
index 00000000000..ba7245b545e
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/2-TSESTree-Tokens.shot
@@ -0,0 +1,36 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-without-value TSESTree - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "var",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/3-Babel-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/3-Babel-AST.shot
new file mode 100644
index 00000000000..a3bb2551bf2
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/3-Babel-AST.shot
@@ -0,0 +1,48 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-without-value Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    VariableDeclaration {
+      type: "VariableDeclaration",
+      declarations: Array [
+        VariableDeclarator {
+          type: "VariableDeclarator",
+          id: Identifier {
+            type: "Identifier",
+            name: "x",
+
+            range: [4, 5],
+            loc: {
+              start: { column: 4, line: 1 },
+              end: { column: 5, line: 1 },
+            },
+          },
+          init: null,
+
+          range: [4, 5],
+          loc: {
+            start: { column: 4, line: 1 },
+            end: { column: 5, line: 1 },
+          },
+        },
+      ],
+      kind: "var",
+
+      range: [0, 6],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 6, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 7],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/4-Babel-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/4-Babel-Tokens.shot
new file mode 100644
index 00000000000..289daee1ace
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/4-Babel-Tokens.shot
@@ -0,0 +1,36 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-without-value Babel - Tokens 1`] = `
+Array [
+  Keyword {
+    type: "Keyword",
+    value: "var",
+
+    range: [0, 3],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 3, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "x",
+
+    range: [4, 5],
+    loc: {
+      start: { column: 4, line: 1 },
+      end: { column: 5, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: ";",
+
+    range: [5, 6],
+    loc: {
+      start: { column: 5, line: 1 },
+      end: { column: 6, line: 1 },
+    },
+  },
+]
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/5-AST-Alignment-AST.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/5-AST-Alignment-AST.shot
new file mode 100644
index 00000000000..b8594239a06
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/5-AST-Alignment-AST.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-without-value AST Alignment - AST 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/6-AST-Alignment-Tokens.shot b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/6-AST-Alignment-Tokens.shot
new file mode 100644
index 00000000000..3d401ca8c69
--- /dev/null
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/fixtures/var-without-value/snapshots/6-AST-Alignment-Tokens.shot
@@ -0,0 +1,6 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration VariableDeclaration var-without-value AST Alignment - Token 1`] = `
+"Snapshot Diff:
+Compared values have no visual difference."
+`;
diff --git a/packages/ast-spec/src/declaration/VariableDeclaration/spec.ts b/packages/ast-spec/src/declaration/VariableDeclaration/spec.ts
index 418a51eb735..4bc9b0f4854 100644
--- a/packages/ast-spec/src/declaration/VariableDeclaration/spec.ts
+++ b/packages/ast-spec/src/declaration/VariableDeclaration/spec.ts
@@ -4,8 +4,31 @@ import type { VariableDeclarator } from '../../special/VariableDeclarator/spec';
 
 export interface VariableDeclaration extends BaseNode {
   type: AST_NODE_TYPES.VariableDeclaration;
-  // NOTE - this is not guaranteed to have any elements in it. i.e. `const;`
+  /**
+   * The variables declared by this declaration.
+   * Note that there may be 0 declarations (i.e. `const;`).
+   * ```
+   * let x;
+   * let y, z;
+   * ```
+   */
+  // TODO(#1852) - this should be guaranteed to have at least 1 element in it.
   declarations: VariableDeclarator[];
-  kind: 'const' | 'let' | 'var';
+  /**
+   * Whether the declaration is `declare`d
+   * ```
+   * declare const x = 1;
+   * ```
+   */
+  // TODO(#5020) - make this `false` if it is not `declare`d
   declare?: boolean;
+  /**
+   * The keyword used to declare the variable(s)
+   * ```
+   * const x = 1;
+   * let y = 2;
+   * var z = 3;
+   * ```
+   */
+  kind: 'const' | 'let' | 'var';
 }
diff --git a/packages/ast-spec/src/expression/ClassExpression/spec.ts b/packages/ast-spec/src/expression/ClassExpression/spec.ts
index 15215c31f1b..dfe6c0d1b41 100644
--- a/packages/ast-spec/src/expression/ClassExpression/spec.ts
+++ b/packages/ast-spec/src/expression/ClassExpression/spec.ts
@@ -1,6 +1,9 @@
 import type { AST_NODE_TYPES } from '../../ast-node-types';
-import type { ClassDeclarationBase } from '../../base/ClassDeclarationBase';
+import type { ClassBase } from '../../base/ClassBase';
 
-export interface ClassExpression extends ClassDeclarationBase {
+export interface ClassExpression extends ClassBase {
   type: AST_NODE_TYPES.ClassExpression;
+  abstract?: undefined;
+  declare?: undefined;
+  decorators?: undefined;
 }
diff --git a/packages/ast-spec/src/expression/FunctionExpression/spec.ts b/packages/ast-spec/src/expression/FunctionExpression/spec.ts
index 111be168b02..41f592a972f 100644
--- a/packages/ast-spec/src/expression/FunctionExpression/spec.ts
+++ b/packages/ast-spec/src/expression/FunctionExpression/spec.ts
@@ -1,8 +1,9 @@
 import type { AST_NODE_TYPES } from '../../ast-node-types';
-import type { FunctionDeclarationBase } from '../../base/FunctionDeclarationBase';
+import type { FunctionBase } from '../../base/FunctionBase';
 import type { BlockStatement } from '../../statement/BlockStatement/spec';
 
-export interface FunctionExpression extends FunctionDeclarationBase {
+export interface FunctionExpression extends FunctionBase {
   type: AST_NODE_TYPES.FunctionExpression;
   body: BlockStatement;
+  expression: false;
 }
diff --git a/packages/ast-spec/src/expression/TSEmptyBodyFunctionExpression/spec.ts b/packages/ast-spec/src/expression/TSEmptyBodyFunctionExpression/spec.ts
index 2cc413c0109..77c8779c7d1 100644
--- a/packages/ast-spec/src/expression/TSEmptyBodyFunctionExpression/spec.ts
+++ b/packages/ast-spec/src/expression/TSEmptyBodyFunctionExpression/spec.ts
@@ -1,7 +1,8 @@
 import type { AST_NODE_TYPES } from '../../ast-node-types';
-import type { FunctionDeclarationBase } from '../../base/FunctionDeclarationBase';
+import type { FunctionBase } from '../../base/FunctionBase';
 
-export interface TSEmptyBodyFunctionExpression extends FunctionDeclarationBase {
+export interface TSEmptyBodyFunctionExpression extends FunctionBase {
   type: AST_NODE_TYPES.TSEmptyBodyFunctionExpression;
   body: null;
+  id: null;
 }
diff --git a/packages/ast-spec/src/special/TSExternalModuleReference/spec.ts b/packages/ast-spec/src/special/TSExternalModuleReference/spec.ts
index e634d4d0d6e..1efd283fd8c 100644
--- a/packages/ast-spec/src/special/TSExternalModuleReference/spec.ts
+++ b/packages/ast-spec/src/special/TSExternalModuleReference/spec.ts
@@ -4,5 +4,6 @@ import type { Expression } from '../../unions/Expression';
 
 export interface TSExternalModuleReference extends BaseNode {
   type: AST_NODE_TYPES.TSExternalModuleReference;
+  // TODO(#1852) - this must be a string
   expression: Expression;
 }
diff --git a/packages/ast-spec/src/unions/ExportDeclaration.ts b/packages/ast-spec/src/unions/ExportDeclaration.ts
index 1ae9d9ddb9f..b78996d1405 100644
--- a/packages/ast-spec/src/unions/ExportDeclaration.ts
+++ b/packages/ast-spec/src/unions/ExportDeclaration.ts
@@ -1,20 +1,48 @@
-import type { ClassDeclaration } from '../declaration/ClassDeclaration/spec';
-import type { FunctionDeclaration } from '../declaration/FunctionDeclaration/spec';
+import type {
+  ClassDeclarationWithName,
+  ClassDeclarationWithOptionalName,
+} from '../declaration/ClassDeclaration/spec';
+import type {
+  FunctionDeclarationWithName,
+  FunctionDeclarationWithOptionalName,
+} from '../declaration/FunctionDeclaration/spec';
 import type { TSDeclareFunction } from '../declaration/TSDeclareFunction/spec';
 import type { TSEnumDeclaration } from '../declaration/TSEnumDeclaration/spec';
 import type { TSInterfaceDeclaration } from '../declaration/TSInterfaceDeclaration/spec';
 import type { TSModuleDeclaration } from '../declaration/TSModuleDeclaration/spec';
 import type { TSTypeAliasDeclaration } from '../declaration/TSTypeAliasDeclaration/spec';
 import type { VariableDeclaration } from '../declaration/VariableDeclaration/spec';
-import type { ClassExpression } from '../expression/ClassExpression/spec';
+import type { Expression } from './Expression';
 
-export type ExportDeclaration =
-  | ClassDeclaration
-  | ClassExpression
-  | FunctionDeclaration
+// TODO(#1852) - the following are disallowed syntactically, but allowed by TS error recovery:
+// TSEnumDeclaration, TSModuleDeclaration, TSTypeAliasDeclaration, VariableDeclaration
+export type DefaultExportDeclarations =
+  | ClassDeclarationWithOptionalName
+  | Expression
+  | FunctionDeclarationWithName
+  | FunctionDeclarationWithOptionalName
+  | TSDeclareFunction
+  | TSEnumDeclaration
+  | TSInterfaceDeclaration
+  | TSModuleDeclaration
+  | TSTypeAliasDeclaration
+  | VariableDeclaration;
+
+// TODO(#1852) - the following are disallowed syntactically, but allowed by TS error recovery:
+// ClassDeclarationWithOptionalName, FunctionDeclarationWithOptionalName
+export type NamedExportDeclarations =
+  | ClassDeclarationWithName
+  | ClassDeclarationWithOptionalName
+  | FunctionDeclarationWithName
+  | FunctionDeclarationWithOptionalName
   | TSDeclareFunction
   | TSEnumDeclaration
   | TSInterfaceDeclaration
   | TSModuleDeclaration
   | TSTypeAliasDeclaration
   | VariableDeclaration;
+
+// TODO - breaking change remove this in the next major
+export type ExportDeclaration =
+  | DefaultExportDeclarations
+  | NamedExportDeclarations;
diff --git a/packages/ast-spec/src/unions/Statement.ts b/packages/ast-spec/src/unions/Statement.ts
index e1af96b7fe5..56a4cfaf1ae 100644
--- a/packages/ast-spec/src/unions/Statement.ts
+++ b/packages/ast-spec/src/unions/Statement.ts
@@ -1,8 +1,8 @@
-import type { ClassDeclaration } from '../declaration/ClassDeclaration/spec';
+import type { ClassDeclarationWithName } from '../declaration/ClassDeclaration/spec';
 import type { ExportAllDeclaration } from '../declaration/ExportAllDeclaration/spec';
 import type { ExportDefaultDeclaration } from '../declaration/ExportDefaultDeclaration/spec';
 import type { ExportNamedDeclaration } from '../declaration/ExportNamedDeclaration/spec';
-import type { FunctionDeclaration } from '../declaration/FunctionDeclaration/spec';
+import type { FunctionDeclarationWithName } from '../declaration/FunctionDeclaration/spec';
 import type { ImportDeclaration } from '../declaration/ImportDeclaration/spec';
 import type { TSDeclareFunction } from '../declaration/TSDeclareFunction/spec';
 import type { TSEnumDeclaration } from '../declaration/TSEnumDeclaration/spec';
@@ -34,7 +34,7 @@ import type { WithStatement } from '../statement/WithStatement/spec';
 export type Statement =
   | BlockStatement
   | BreakStatement
-  | ClassDeclaration
+  | ClassDeclarationWithName
   | ContinueStatement
   | DebuggerStatement
   | DoWhileStatement
@@ -45,7 +45,7 @@ export type Statement =
   | ForInStatement
   | ForOfStatement
   | ForStatement
-  | FunctionDeclaration
+  | FunctionDeclarationWithName
   | IfStatement
   | ImportDeclaration
   | LabeledStatement
@@ -75,4 +75,4 @@ export type ProgramStatement =
   | TSImportEqualsDeclaration
   | TSNamespaceExportDeclaration;
 
-// TODO - once we have syntax errors, the types in ProgramStatement should not be in Statement
+// TODO(#1852) - the types in ProgramStatement should not be in Statement
diff --git a/packages/ast-spec/tests/fixtures-with-differences-ast.shot b/packages/ast-spec/tests/fixtures-with-differences-ast.shot
index 2a37d6b6582..9d3e5d88ccc 100644
--- a/packages/ast-spec/tests/fixtures-with-differences-ast.shot
+++ b/packages/ast-spec/tests/fixtures-with-differences-ast.shot
@@ -4,13 +4,25 @@ exports[`AST Fixtures List fixtures with AST differences 1`] = `
 Set {
   "declaration/ClassDeclaration/fixtures/implements-many/fixture.ts",
   "declaration/ClassDeclaration/fixtures/implements-one/fixture.ts",
-  "declaration/ClassDeclaration/fixtures/type-parameters-extends-type-parameters/fixture.ts",
-  "declaration/ClassDeclaration/fixtures/type-parameters/fixture.ts",
+  "declaration/ClassDeclaration/fixtures/type-param/fixture.ts",
+  "declaration/ClassDeclaration/fixtures/type-parameters-extends-type-param/fixture.ts",
+  "declaration/ClassDeclaration/fixtures/with-member-one/fixture.ts",
   "declaration/ExportNamedDeclaration/fixtures/aliased/fixture.ts",
   "declaration/ExportNamedDeclaration/fixtures/declare-function/fixture.ts",
   "declaration/ExportNamedDeclaration/fixtures/identifier-braced/fixture.ts",
   "declaration/ExportNamedDeclaration/fixtures/identifier-many/fixture.ts",
   "declaration/ExportNamedDeclaration/fixtures/interface/fixture.ts",
   "declaration/ExportNamedDeclaration/fixtures/type-alias/fixture.ts",
+  "declaration/FunctionDeclaration/fixtures/type-param-many/fixture.ts",
+  "declaration/FunctionDeclaration/fixtures/type-param-one/fixture.ts",
+  "declaration/TSDeclareFunction/fixtures/type-param-many/fixture.ts",
+  "declaration/TSDeclareFunction/fixtures/type-param-one/fixture.ts",
+  "declaration/TSImportEqualsDeclaration/fixtures/external-module-ref-string/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/extends-many/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/extends-one/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/type-param-many/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/type-param-one/fixture.ts",
+  "declaration/TSTypeAliasDeclaration/fixtures/type-param-many/fixture.ts",
+  "declaration/TSTypeAliasDeclaration/fixtures/type-param-one/fixture.ts",
 }
 `;
diff --git a/packages/ast-spec/tests/fixtures-with-differences-errors.shot b/packages/ast-spec/tests/fixtures-with-differences-errors.shot
index 59b5c479a75..f9c7ef6147d 100644
--- a/packages/ast-spec/tests/fixtures-with-differences-errors.shot
+++ b/packages/ast-spec/tests/fixtures-with-differences-errors.shot
@@ -4,8 +4,22 @@ exports[`AST Fixtures List fixtures with Error differences 1`] = `
 Object {
   "Babel errored but TSESTree didn't": Set {
     "declaration/ClassDeclaration/fixtures/_error_/implements-non-identifier/fixture.ts",
+    "declaration/ClassDeclaration/fixtures/_error_/missing-extends-type-param/fixture.ts",
+    "declaration/ClassDeclaration/fixtures/_error_/missing-type-param/fixture.ts",
+    "declaration/ExportAllDeclaration/fixtures/_error_/kind-type/fixture.ts",
     "declaration/ExportAllDeclaration/fixtures/_error_/type-kind/fixture.ts",
     "declaration/ExportNamedDeclaration/fixtures/_error_/anonymous-class/fixture.ts",
+    "declaration/FunctionDeclaration/fixtures/_error_/missing-type-param/fixture.ts",
+    "declaration/TSDeclareFunction/fixtures/_error_/async/fixture.ts",
+    "declaration/TSDeclareFunction/fixtures/_error_/declare-with-body/fixture.ts",
+    "declaration/TSDeclareFunction/fixtures/_error_/missing-type-param/fixture.ts",
+    "declaration/TSImportEqualsDeclaration/fixtures/_error_/external-module-ref-non-string/fixture.ts",
+    "declaration/TSImportEqualsDeclaration/fixtures/_error_/import-kind/fixture.ts",
+    "declaration/TSInterfaceDeclaration/fixtures/_error_/missing-extends/fixture.ts",
+    "declaration/TSInterfaceDeclaration/fixtures/_error_/missing-type-param/fixture.ts",
+    "declaration/TSInterfaceDeclaration/fixtures/_error_/non-identifier-extends/fixture.ts",
+    "declaration/TSTypeAliasDeclaration/fixtures/_error_/missing-type-parameter/fixture.ts",
+    "declaration/VariableDeclaration/fixtures/_error_/missing-id-without-value/fixture.ts",
   },
   "TSESTree errored but Babel didn't": Set {
     "declaration/ExportAllDeclaration/fixtures/_error_/named-non-identifier/fixture.ts",
diff --git a/packages/ast-spec/tests/fixtures-with-differences-tokens.shot b/packages/ast-spec/tests/fixtures-with-differences-tokens.shot
index 6c8d721a41a..ee92fc9b050 100644
--- a/packages/ast-spec/tests/fixtures-with-differences-tokens.shot
+++ b/packages/ast-spec/tests/fixtures-with-differences-tokens.shot
@@ -7,5 +7,20 @@ Set {
   "declaration/ExportDefaultDeclaration/fixtures/interface/fixture.ts",
   "declaration/ExportNamedDeclaration/fixtures/enum/fixture.ts",
   "declaration/ExportNamedDeclaration/fixtures/interface/fixture.ts",
+  "declaration/TSEnumDeclaration/fixtures/const/fixture.ts",
+  "declaration/TSEnumDeclaration/fixtures/declare/fixture.ts",
+  "declaration/TSEnumDeclaration/fixtures/empty/fixture.ts",
+  "declaration/TSEnumDeclaration/fixtures/with-member-one/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/declare/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/empty/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/extends-many/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/extends-one/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/type-param-many/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/type-param-one/fixture.ts",
+  "declaration/TSInterfaceDeclaration/fixtures/with-member-one/fixture.ts",
+  "declaration/VariableDeclaration/fixtures/declare/fixture.ts",
+  "declaration/VariableDeclaration/fixtures/let-with-value/fixture.ts",
+  "declaration/VariableDeclaration/fixtures/let-without-value/fixture.ts",
+  "declaration/VariableDeclaration/fixtures/multiple-declarations/fixture.ts",
 }
 `;
diff --git a/packages/typescript-estree/src/convert.ts b/packages/typescript-estree/src/convert.ts
index af75c6ce428..9e576429690 100644
--- a/packages/typescript-estree/src/convert.ts
+++ b/packages/typescript-estree/src/convert.ts
@@ -142,7 +142,11 @@ export class Converter {
    * @param result result
    * @returns the ESTreeNode with fixed exports
    */
-  private fixExports<T extends TSESTree.ExportDeclaration>(
+  private fixExports<
+    T extends
+      | TSESTree.DefaultExportDeclarations
+      | TSESTree.NamedExportDeclarations,
+  >(
     node:
       | ts.FunctionDeclaration
       | ts.VariableStatement
@@ -184,9 +188,10 @@ export class Converter {
         const isType =
           result.type === AST_NODE_TYPES.TSInterfaceDeclaration ||
           result.type === AST_NODE_TYPES.TSTypeAliasDeclaration;
-        const isDeclare = result.declare === true;
+        const isDeclare = 'declare' in result && result.declare === true;
         return this.createNode<TSESTree.ExportNamedDeclaration>(node, {
           type: AST_NODE_TYPES.ExportNamedDeclaration,
+          // @ts-expect-error - TODO, narrow the types here
           declaration: result,
           specifiers: [],
           source: null,
@@ -745,10 +750,19 @@ export class Converter {
 
   private assertModuleSpecifier(
     node: ts.ExportDeclaration | ts.ImportDeclaration,
+    allowNull: boolean,
   ): void {
+    if (!allowNull && node.moduleSpecifier == null) {
+      throw createError(
+        this.ast,
+        node.pos,
+        'Module specifier must be a string literal.',
+      );
+    }
+
     if (
       node.moduleSpecifier &&
-      node.moduleSpecifier.kind !== SyntaxKind.StringLiteral
+      node.moduleSpecifier?.kind !== SyntaxKind.StringLiteral
     ) {
       throw createError(
         this.ast,
@@ -964,10 +978,6 @@ export class Converter {
           result.returnType = this.convertTypeAnnotation(node.type, node);
         }
 
-        if (isDeclare) {
-          result.declare = true;
-        }
-
         // Process typeParameters
         if (node.typeParameters) {
           result.typeParameters =
@@ -976,6 +986,10 @@ export class Converter {
             );
         }
 
+        if (isDeclare) {
+          result.declare = true;
+        }
+
         // check for exports
         return this.fixExports(node, result);
       }
@@ -1737,7 +1751,7 @@ export class Converter {
         });
 
       case SyntaxKind.ImportDeclaration: {
-        this.assertModuleSpecifier(node);
+        this.assertModuleSpecifier(node, false);
 
         const result = this.createNode<TSESTree.ImportDeclaration>(node, {
           type: AST_NODE_TYPES.ImportDeclaration,
@@ -1804,8 +1818,8 @@ export class Converter {
       }
 
       case SyntaxKind.ExportDeclaration: {
-        this.assertModuleSpecifier(node);
         if (node.exportClause?.kind === SyntaxKind.NamedExports) {
+          this.assertModuleSpecifier(node, true);
           return this.createNode<TSESTree.ExportNamedDeclaration>(node, {
             type: AST_NODE_TYPES.ExportNamedDeclaration,
             source: this.convertChild(node.moduleSpecifier),
@@ -1817,6 +1831,7 @@ export class Converter {
             assertions: this.convertAssertClasue(node.assertClause),
           });
         } else {
+          this.assertModuleSpecifier(node, false);
           return this.createNode<TSESTree.ExportAllDeclaration>(node, {
             type: AST_NODE_TYPES.ExportAllDeclaration,
             source: this.convertChild(node.moduleSpecifier),