From c87b672bbdcbd961daa129600aabec565ef803d9 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Thu, 15 Oct 2020 12:19:16 +0900
Subject: [PATCH 01/25] Install babel/parser 7.12

---
 package.json | 2 +-
 yarn.lock    | 7 ++++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index 9b2276dcb25d..dc27a4ab89ed 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
   "dependencies": {
     "@angular/compiler": "10.1.5",
     "@babel/code-frame": "7.10.4",
-    "@babel/parser": "7.11.5",
+    "@babel/parser": "7.12.0",
     "@glimmer/syntax": "0.62.1",
     "@iarna/toml": "2.2.5",
     "@typescript-eslint/typescript-estree": "3.10.1",
diff --git a/yarn.lock b/yarn.lock
index 15636396a725..5d910f306db6 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -279,7 +279,12 @@
     chalk "^2.0.0"
     js-tokens "^4.0.0"
 
-"@babel/parser@7.11.5", "@babel/parser@^7.1.0", "@babel/parser@^7.10.4", "@babel/parser@^7.11.5", "@babel/parser@^7.7.0":
+"@babel/parser@7.12.0":
+  version "7.12.0"
+  resolved "https://registry.yarnpkg.com/@babel/parser/-/parser-7.12.0.tgz#2ad388f3960045b22f9b7d4bf85e80b15a1c9e3a"
+  integrity sha512-dYmySMYnlus2jwl7JnnajAj11obRStZoW9cG04wh4ZuhozDn11tDUrhHcUZ9iuNHqALAhh60XqNaYXpvuuE/Gg==
+
+"@babel/parser@^7.1.0", "@babel/parser@^7.10.4", "@babel/parser@^7.11.5", "@babel/parser@^7.7.0":
   version "7.11.5"
   resolved "https://registry.yarnpkg.com/@babel/parser/-/parser-7.11.5.tgz#c7ff6303df71080ec7a4f5b8c003c58f1cf51037"
   integrity sha512-X9rD8qqm695vgmeaQ4fvz/o3+Wk4ZzQvSHkDBgpYKxpD4qTAUm88ZKtHkVqIOsYFFbIQ6wQYhC6q7pjqVK0E0Q==

From b5308bd7e6df0fb94a76f684e4979171cc5e72ce Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Thu, 15 Oct 2020 16:37:36 +0900
Subject: [PATCH 02/25] Add tests for babel/babel#12161

---
 src/language-js/printer-estree.js                         | 3 ++-
 .../misc/errors/babel-ts/__snapshots__/jsfmt.spec.js.snap | 8 ++++----
 tests/misc/errors/babel-ts/issue-8041.ts                  | 1 -
 tests/misc/errors/babel-ts/type-annotation.ts             | 1 +
 4 files changed, 7 insertions(+), 6 deletions(-)
 delete mode 100644 tests/misc/errors/babel-ts/issue-8041.ts
 create mode 100644 tests/misc/errors/babel-ts/type-annotation.ts

diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index e303d3cf2bd8..c17df7b7ecfd 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -2886,7 +2886,8 @@ function printPathNoParens(path, options, print, args) {
 
       return group(concat(parts));
     }
-    case "TypeCastExpression": {
+    case "TypeCastExpression":
+    case "TSTypeCastExpression": {
       return concat([
         "(",
         path.call(print, "expression"),
diff --git a/tests/misc/errors/babel-ts/__snapshots__/jsfmt.spec.js.snap b/tests/misc/errors/babel-ts/__snapshots__/jsfmt.spec.js.snap
index f7efaedf67d4..6d96116982a4 100644
--- a/tests/misc/errors/babel-ts/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/misc/errors/babel-ts/__snapshots__/jsfmt.spec.js.snap
@@ -1,8 +1,8 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`issue-8041.ts error test 1`] = `
-"Did not expect a type annotation here. (1:2)
-> 1 | (a:b)
-    |  ^
+exports[`type-annotation.ts error test 1`] = `
+"Did not expect a type annotation here. (1:9)
+> 1 | func<T>(a: T);
+    |         ^
   2 | "
 `;
diff --git a/tests/misc/errors/babel-ts/issue-8041.ts b/tests/misc/errors/babel-ts/issue-8041.ts
deleted file mode 100644
index 4163d9c50531..000000000000
--- a/tests/misc/errors/babel-ts/issue-8041.ts
+++ /dev/null
@@ -1 +0,0 @@
-(a:b)
diff --git a/tests/misc/errors/babel-ts/type-annotation.ts b/tests/misc/errors/babel-ts/type-annotation.ts
new file mode 100644
index 000000000000..837f402397e7
--- /dev/null
+++ b/tests/misc/errors/babel-ts/type-annotation.ts
@@ -0,0 +1 @@
+func<T>(a: T);

From 7979066a85168804ce63cf59c8f0c73a4e58c9d5 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Thu, 15 Oct 2020 23:29:41 +0900
Subject: [PATCH 03/25] Add test for babel/babel#12076

---
 tests/js/objects/__snapshots__/jsfmt.spec.js.snap | 14 ++++++++++++++
 tests/js/objects/invalid-setter.js                |  1 +
 tests/js/objects/jsfmt.spec.js                    |  8 +++++++-
 3 files changed, 22 insertions(+), 1 deletion(-)
 create mode 100644 tests/js/objects/invalid-setter.js

diff --git a/tests/js/objects/__snapshots__/jsfmt.spec.js.snap b/tests/js/objects/__snapshots__/jsfmt.spec.js.snap
index fe84e6fa3470..e47156c4dc6d 100644
--- a/tests/js/objects/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/js/objects/__snapshots__/jsfmt.spec.js.snap
@@ -143,6 +143,20 @@ printWidth: 80
 ================================================================================
 `;
 
+exports[`invalid-setter.js format 1`] = `
+====================================options=====================================
+parsers: ["babel"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+({ set x(){} });
+
+=====================================output=====================================
+({ set x() {} });
+
+================================================================================
+`;
+
 exports[`method.js format 1`] = `
 ====================================options=====================================
 parsers: ["babel"]
diff --git a/tests/js/objects/invalid-setter.js b/tests/js/objects/invalid-setter.js
new file mode 100644
index 000000000000..0dcad3093338
--- /dev/null
+++ b/tests/js/objects/invalid-setter.js
@@ -0,0 +1 @@
+({ set x(){} });
diff --git a/tests/js/objects/jsfmt.spec.js b/tests/js/objects/jsfmt.spec.js
index b113fb8352d0..5ac39ca0386f 100644
--- a/tests/js/objects/jsfmt.spec.js
+++ b/tests/js/objects/jsfmt.spec.js
@@ -1,3 +1,9 @@
 run_spec(__dirname, ["babel"], {
-  errors: { espree: ["expression.js", "invalid-accessor-generator.js"] },
+  errors: {
+    espree: [
+      "expression.js",
+      "invalid-accessor-generator.js",
+      "invalid-setter.js",
+    ]
+  },
 });

From b19743ffc6c28a98553ed3751ac85f1e0fdc4cd3 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Thu, 15 Oct 2020 23:35:35 +0900
Subject: [PATCH 04/25] Add test for babel/babel#12085

---
 tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap | 4 ++++
 tests/typescript/declare/declare_function.ts              | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap b/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
index 82d434d08950..fba2ff4d264e 100644
--- a/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
@@ -50,6 +50,8 @@ declare namespace A {
     function y(): void;
 }
 
+declare function f([]?)
+
 =====================================output=====================================
 declare function x();
 declare function y(): void;
@@ -59,6 +61,8 @@ declare namespace A {
   function y(): void;
 }
 
+declare function f([]?);
+
 ================================================================================
 `;
 
diff --git a/tests/typescript/declare/declare_function.ts b/tests/typescript/declare/declare_function.ts
index 67710eb24f78..d6b56a0c2c05 100644
--- a/tests/typescript/declare/declare_function.ts
+++ b/tests/typescript/declare/declare_function.ts
@@ -5,3 +5,5 @@ declare namespace A {
     function x();
     function y(): void;
 }
+
+declare function f([]?)

From d599e726a3515a8fd6f45ec330d91376574ffc5c Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Thu, 15 Oct 2020 23:47:31 +0900
Subject: [PATCH 05/25] Add test for babel/babel#12108

---
 .../declare/__snapshots__/jsfmt.spec.js.snap  | 50 +++++++++++++++++++
 .../declare/declare_class_fields.ts           |  3 ++
 tests/typescript/declare/declare_module.ts    |  5 ++
 tests/typescript/declare/declare_namespace.ts |  5 ++
 4 files changed, 63 insertions(+)
 create mode 100644 tests/typescript/declare/declare_module.ts
 create mode 100644 tests/typescript/declare/declare_namespace.ts

diff --git a/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap b/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
index fba2ff4d264e..1fcc04e83438 100644
--- a/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
@@ -8,6 +8,9 @@ printWidth: 80
 =====================================input======================================
 class B {p: number;}
 class C extends B {declare p: 256 | 1000;}
+declare class D {
+  field = "field";
+}
 
 =====================================output=====================================
 class B {
@@ -16,6 +19,9 @@ class B {
 class C extends B {
   declare p: 256 | 1000;
 }
+declare class D {
+  field = "field";
+}
 
 ================================================================================
 `;
@@ -84,6 +90,50 @@ declare interface Dictionary<T> {
 ================================================================================
 `;
 
+exports[`declare_module.ts format 1`] = `
+====================================options=====================================
+parsers: ["typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+declare module m {
+  class C {
+    field = "field";
+  }
+}
+
+=====================================output=====================================
+declare module m {
+  class C {
+    field = "field";
+  }
+}
+
+================================================================================
+`;
+
+exports[`declare_namespace.ts format 1`] = `
+====================================options=====================================
+parsers: ["typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+declare namespace m {
+  class C {
+    field = "field";
+  }
+}
+
+=====================================output=====================================
+declare namespace m {
+  class C {
+    field = "field";
+  }
+}
+
+================================================================================
+`;
+
 exports[`declare_var.ts format 1`] = `
 ====================================options=====================================
 parsers: ["typescript"]
diff --git a/tests/typescript/declare/declare_class_fields.ts b/tests/typescript/declare/declare_class_fields.ts
index 447d7a37ef53..aaa8193f812e 100644
--- a/tests/typescript/declare/declare_class_fields.ts
+++ b/tests/typescript/declare/declare_class_fields.ts
@@ -1,2 +1,5 @@
 class B {p: number;}
 class C extends B {declare p: 256 | 1000;}
+declare class D {
+  field = "field";
+}
diff --git a/tests/typescript/declare/declare_module.ts b/tests/typescript/declare/declare_module.ts
new file mode 100644
index 000000000000..3e9ccd1749f7
--- /dev/null
+++ b/tests/typescript/declare/declare_module.ts
@@ -0,0 +1,5 @@
+declare module m {
+  class C {
+    field = "field";
+  }
+}
diff --git a/tests/typescript/declare/declare_namespace.ts b/tests/typescript/declare/declare_namespace.ts
new file mode 100644
index 000000000000..9d74551c7292
--- /dev/null
+++ b/tests/typescript/declare/declare_namespace.ts
@@ -0,0 +1,5 @@
+declare namespace m {
+  class C {
+    field = "field";
+  }
+}

From 7417d90a16b549fe9eeb0409efbee1229ba0a7a1 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Fri, 16 Oct 2020 00:08:25 +0900
Subject: [PATCH 06/25] Add test for babel/babel#12120

---
 tests/js/objects/jsfmt.spec.js                     |  2 +-
 .../__snapshots__/jsfmt.spec.js.snap               | 14 ++++++++++++++
 tests/js/variable_declarator/invalid-const.js      |  1 +
 tests/js/variable_declarator/jsfmt.spec.js         |  7 ++++++-
 4 files changed, 22 insertions(+), 2 deletions(-)
 create mode 100644 tests/js/variable_declarator/invalid-const.js

diff --git a/tests/js/objects/jsfmt.spec.js b/tests/js/objects/jsfmt.spec.js
index 5ac39ca0386f..74867c290696 100644
--- a/tests/js/objects/jsfmt.spec.js
+++ b/tests/js/objects/jsfmt.spec.js
@@ -4,6 +4,6 @@ run_spec(__dirname, ["babel"], {
       "expression.js",
       "invalid-accessor-generator.js",
       "invalid-setter.js",
-    ]
+    ],
   },
 });
diff --git a/tests/js/variable_declarator/__snapshots__/jsfmt.spec.js.snap b/tests/js/variable_declarator/__snapshots__/jsfmt.spec.js.snap
index 8176ccad8608..a89b178417dc 100644
--- a/tests/js/variable_declarator/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/js/variable_declarator/__snapshots__/jsfmt.spec.js.snap
@@ -1,5 +1,19 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`invalid-const.js format 1`] = `
+====================================options=====================================
+parsers: ["babel", "flow", "typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+const foo;
+
+=====================================output=====================================
+const foo;
+
+================================================================================
+`;
+
 exports[`multiple.js format 1`] = `
 ====================================options=====================================
 parsers: ["babel", "flow", "typescript"]
diff --git a/tests/js/variable_declarator/invalid-const.js b/tests/js/variable_declarator/invalid-const.js
new file mode 100644
index 000000000000..f15614ea39c3
--- /dev/null
+++ b/tests/js/variable_declarator/invalid-const.js
@@ -0,0 +1 @@
+const foo;
diff --git a/tests/js/variable_declarator/jsfmt.spec.js b/tests/js/variable_declarator/jsfmt.spec.js
index eb85eda6bd02..7ad187763274 100644
--- a/tests/js/variable_declarator/jsfmt.spec.js
+++ b/tests/js/variable_declarator/jsfmt.spec.js
@@ -1 +1,6 @@
-run_spec(__dirname, ["babel", "flow", "typescript"]);
+run_spec(__dirname, ["babel", "flow", "typescript"], {
+  errors: {
+    espree: ["invalid-const.js"],
+    flow: ["invalid-const.js"],
+  },
+});

From cf0ed635d42c0519561cae4340ab5aaec1150679 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Fri, 16 Oct 2020 00:27:58 +0900
Subject: [PATCH 07/25] Add test for babel/babel#12054

---
 src/language-js/printer-estree.js             |  3 ++-
 .../declare/__snapshots__/jsfmt.spec.js.snap  | 22 +++++++++++++++++++
 .../declare/declare_function_with_body.ts     |  5 +++++
 3 files changed, 29 insertions(+), 1 deletion(-)
 create mode 100644 tests/typescript/declare/declare_function_with_body.ts

diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index c17df7b7ecfd..ab57ee5b3c48 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -913,7 +913,8 @@ function printPathNoParens(path, options, print, args) {
           parent.type === "DoWhileStatement" ||
           parent.type === "DoExpression" ||
           (parent.type === "CatchClause" && !parentParent.finalizer) ||
-          parent.type === "TSModuleDeclaration")
+          parent.type === "TSModuleDeclaration" ||
+          parent.type === "TSDeclareFunction")
       ) {
         return "{}";
       }
diff --git a/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap b/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
index 1fcc04e83438..cf4b00955da3 100644
--- a/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
@@ -72,6 +72,28 @@ declare function f([]?);
 ================================================================================
 `;
 
+exports[`declare_function_with_body.ts format 1`] = `
+====================================options=====================================
+parsers: ["typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+// Invalid, but recoverable
+declare function foo() {}
+declare function bar() {
+  // comment
+}
+
+=====================================output=====================================
+// Invalid, but recoverable
+declare function foo() {};
+declare function bar() {
+  // comment
+};
+
+================================================================================
+`;
+
 exports[`declare_interface.ts format 1`] = `
 ====================================options=====================================
 parsers: ["typescript"]
diff --git a/tests/typescript/declare/declare_function_with_body.ts b/tests/typescript/declare/declare_function_with_body.ts
new file mode 100644
index 000000000000..34c28e8fc893
--- /dev/null
+++ b/tests/typescript/declare/declare_function_with_body.ts
@@ -0,0 +1,5 @@
+// Invalid, but recoverable
+declare function foo() {}
+declare function bar() {
+  // comment
+}

From 2e42f06480232eec17f887adc39aaac740133caf Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Fri, 16 Oct 2020 00:40:25 +0900
Subject: [PATCH 08/25] Add test for babel/babel#12061

---
 .../types/parameterProperty/__snapshots__/jsfmt.spec.js.snap   | 3 +++
 .../conformance/types/parameterProperty/parameterProperty.ts   | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/tests/typescript/conformance/types/parameterProperty/__snapshots__/jsfmt.spec.js.snap b/tests/typescript/conformance/types/parameterProperty/__snapshots__/jsfmt.spec.js.snap
index 46af62801656..1fc8509a406f 100644
--- a/tests/typescript/conformance/types/parameterProperty/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/typescript/conformance/types/parameterProperty/__snapshots__/jsfmt.spec.js.snap
@@ -10,6 +10,8 @@ class c3 {
   constructor(public arg: number = 10) {
     // fails because of comment
   }
+  not_constructor(public arg: number = 10) {
+  }
 }
 
 =====================================output=====================================
@@ -17,6 +19,7 @@ class c3 {
   constructor(public arg: number = 10) {
     // fails because of comment
   }
+  not_constructor(public arg: number = 10) {}
 }
 
 ================================================================================
diff --git a/tests/typescript/conformance/types/parameterProperty/parameterProperty.ts b/tests/typescript/conformance/types/parameterProperty/parameterProperty.ts
index 7928eb4ca428..56527665c176 100644
--- a/tests/typescript/conformance/types/parameterProperty/parameterProperty.ts
+++ b/tests/typescript/conformance/types/parameterProperty/parameterProperty.ts
@@ -2,4 +2,6 @@ class c3 {
   constructor(public arg: number = 10) {
     // fails because of comment
   }
+  not_constructor(public arg: number = 10) {
+  }
 }

From 6c20b0dc7c2d76fbd0804f1e015c05eb28e4d04a Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Fri, 16 Oct 2020 01:06:39 +0900
Subject: [PATCH 09/25] Add test babel/babel#12093

---
 tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap | 6 ++++++
 tests/typescript/declare/declare_class_fields.ts          | 3 +++
 2 files changed, 9 insertions(+)

diff --git a/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap b/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
index cf4b00955da3..9f673f0da2f3 100644
--- a/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/typescript/declare/__snapshots__/jsfmt.spec.js.snap
@@ -8,6 +8,9 @@ printWidth: 80
 =====================================input======================================
 class B {p: number;}
 class C extends B {declare p: 256 | 1000;}
+class D {
+  declare field = "field";
+}
 declare class D {
   field = "field";
 }
@@ -19,6 +22,9 @@ class B {
 class C extends B {
   declare p: 256 | 1000;
 }
+class D {
+  declare field = "field";
+}
 declare class D {
   field = "field";
 }
diff --git a/tests/typescript/declare/declare_class_fields.ts b/tests/typescript/declare/declare_class_fields.ts
index aaa8193f812e..d805d9997f0a 100644
--- a/tests/typescript/declare/declare_class_fields.ts
+++ b/tests/typescript/declare/declare_class_fields.ts
@@ -1,5 +1,8 @@
 class B {p: number;}
 class C extends B {declare p: 256 | 1000;}
+class D {
+  declare field = "field";
+}
 declare class D {
   field = "field";
 }

From 58cbf8b1aef93279fe65a19930f8e4b575939b71 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Fri, 16 Oct 2020 01:23:46 +0900
Subject: [PATCH 10/25] Add test for babel/babel#12065

---
 tests/typescript/class/__snapshots__/jsfmt.spec.js.snap | 8 ++++++++
 tests/typescript/class/constructor.ts                   | 4 ++++
 2 files changed, 12 insertions(+)

diff --git a/tests/typescript/class/__snapshots__/jsfmt.spec.js.snap b/tests/typescript/class/__snapshots__/jsfmt.spec.js.snap
index 1928de49ef7b..c8f5488ae1a5 100644
--- a/tests/typescript/class/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/typescript/class/__snapshots__/jsfmt.spec.js.snap
@@ -21,6 +21,10 @@ class A {
     }
 }
 
+class B {
+  constructor<>() {}
+}
+
 =====================================output=====================================
 class foo {
   constructor(static a: number) {}
@@ -37,6 +41,10 @@ class A {
   }
 }
 
+class B {
+  constructor<>() {}
+}
+
 ================================================================================
 `;
 
diff --git a/tests/typescript/class/constructor.ts b/tests/typescript/class/constructor.ts
index 86297c73acfd..9934c471ab5a 100644
--- a/tests/typescript/class/constructor.ts
+++ b/tests/typescript/class/constructor.ts
@@ -12,3 +12,7 @@ class A {
         return new A()
     }
 }
+
+class B {
+  constructor<>() {}
+}

From cab1ee70ad49999dde4691284bf0ba728bd9e2b2 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Sat, 17 Oct 2020 00:32:08 +0900
Subject: [PATCH 11/25] Add test for babel/babel#12111

---
 src/language-js/printer-estree.js             |  1 +
 .../__snapshots__/jsfmt.spec.js.snap          | 20 +++++++++++++++++++
 .../declare-index-signature.ts                |  4 ++++
 3 files changed, 25 insertions(+)
 create mode 100644 tests/misc/typescript-babel-only/declare-index-signature.ts

diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index ab57ee5b3c48..6d0d8c8b356b 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -3118,6 +3118,7 @@ function printPathNoParens(path, options, print, args) {
         n.accessibility ? concat([n.accessibility, " "]) : "",
         n.static ? "static " : "",
         n.readonly ? "readonly " : "",
+        n.declare ? "declare " : "",
         "[",
         n.parameters ? parametersGroup : "",
         n.typeAnnotation ? "]: " : "]",
diff --git a/tests/misc/typescript-babel-only/__snapshots__/jsfmt.spec.js.snap b/tests/misc/typescript-babel-only/__snapshots__/jsfmt.spec.js.snap
index 42500d9ead56..2d7dba38a3f5 100644
--- a/tests/misc/typescript-babel-only/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/misc/typescript-babel-only/__snapshots__/jsfmt.spec.js.snap
@@ -1,5 +1,25 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`declare-index-signature.ts format 1`] = `
+====================================options=====================================
+parsers: ["babel-ts"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+// Invalid, but recoverable
+class C {
+  declare [key: string]: string;
+}
+
+=====================================output=====================================
+// Invalid, but recoverable
+class C {
+  declare [key: string]: string;
+}
+
+================================================================================
+`;
+
 exports[`tuple-labeled-ts.ts format 1`] = `
 ====================================options=====================================
 parsers: ["babel-ts"]
diff --git a/tests/misc/typescript-babel-only/declare-index-signature.ts b/tests/misc/typescript-babel-only/declare-index-signature.ts
new file mode 100644
index 000000000000..2ba1b7e1c876
--- /dev/null
+++ b/tests/misc/typescript-babel-only/declare-index-signature.ts
@@ -0,0 +1,4 @@
+// Invalid, but recoverable
+class C {
+  declare [key: string]: string;
+}

From e41828240d390fc845119fbead2d94856e2c4672 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Sat, 17 Oct 2020 00:59:01 +0900
Subject: [PATCH 12/25] Add test for babel/babel#12072

---
 tests/js/literal/__snapshots__/jsfmt.spec.js.snap | 14 ++++++++++++++
 tests/js/literal/invalid-exponent.js              |  1 +
 tests/js/literal/jsfmt.spec.js                    |  4 +++-
 3 files changed, 18 insertions(+), 1 deletion(-)
 create mode 100644 tests/js/literal/invalid-exponent.js

diff --git a/tests/js/literal/__snapshots__/jsfmt.spec.js.snap b/tests/js/literal/__snapshots__/jsfmt.spec.js.snap
index 272a89dc91bb..0f5a81730ae3 100644
--- a/tests/js/literal/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/js/literal/__snapshots__/jsfmt.spec.js.snap
@@ -1,5 +1,19 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`invalid-exponent.js format 1`] = `
+====================================options=====================================
+parsers: ["babel", "typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+12.3e
+
+=====================================output=====================================
+12.3e;
+
+================================================================================
+`;
+
 exports[`number.js format 1`] = `
 ====================================options=====================================
 parsers: ["babel", "typescript"]
diff --git a/tests/js/literal/invalid-exponent.js b/tests/js/literal/invalid-exponent.js
new file mode 100644
index 000000000000..979d49d447f1
--- /dev/null
+++ b/tests/js/literal/invalid-exponent.js
@@ -0,0 +1 @@
+12.3e
diff --git a/tests/js/literal/jsfmt.spec.js b/tests/js/literal/jsfmt.spec.js
index 23f3c3a3b6e6..6c46c013dc71 100644
--- a/tests/js/literal/jsfmt.spec.js
+++ b/tests/js/literal/jsfmt.spec.js
@@ -1,2 +1,4 @@
 // flow-parser@0.38.0 fails to parse `1.e1`, so use babel here.
-run_spec(__dirname, ["babel", "typescript"], { errors: { espree: true } });
+run_spec(__dirname, ["babel", "typescript"], {
+  errors: { espree: true, typescript: ["invalid-exponent.js"] },
+});

From d2365f674138e7510597c418d4e417a650ffc9e5 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Sun, 18 Oct 2020 18:11:09 +0900
Subject: [PATCH 13/25] Switch syntax-module-attributes to
 syntax-import-assertion

---
 src/language-js/parser-babel.js               |  2 +-
 src/language-js/printer-estree.js             |  8 ++-
 .../__snapshots__/jsfmt.spec.js.snap          | 56 +++++++++----------
 .../import-assertions-dynamic.js              |  1 +
 .../babel-plugins/import-assertions-static.js |  1 +
 tests/js/babel-plugins/jsfmt.spec.js          |  4 +-
 .../module-attributes-dynamic.js              |  1 -
 .../babel-plugins/module-attributes-static.js |  1 -
 .../__snapshots__/jsfmt.spec.js.snap          | 43 ++++++++++++++
 .../import-assertions-dynamic.js              |  1 +
 .../import-assertions-multi-types.js          |  1 +
 .../import-assertions-static.js               |  1 +
 .../jsfmt.spec.js                             |  0
 .../__snapshots__/jsfmt.spec.js.snap          | 29 ----------
 .../module-attributes-dynamic.js              |  1 -
 .../module-attributes-static.js               |  1 -
 16 files changed, 85 insertions(+), 66 deletions(-)
 create mode 100644 tests/js/babel-plugins/import-assertions-dynamic.js
 create mode 100644 tests/js/babel-plugins/import-assertions-static.js
 delete mode 100644 tests/js/babel-plugins/module-attributes-dynamic.js
 delete mode 100644 tests/js/babel-plugins/module-attributes-static.js
 create mode 100644 tests/js/import-assertions/__snapshots__/jsfmt.spec.js.snap
 create mode 100644 tests/js/import-assertions/import-assertions-dynamic.js
 create mode 100644 tests/js/import-assertions/import-assertions-multi-types.js
 create mode 100644 tests/js/import-assertions/import-assertions-static.js
 rename tests/js/{module-attributes => import-assertions}/jsfmt.spec.js (100%)
 delete mode 100644 tests/js/module-attributes/__snapshots__/jsfmt.spec.js.snap
 delete mode 100644 tests/js/module-attributes/module-attributes-dynamic.js
 delete mode 100644 tests/js/module-attributes/module-attributes-static.js

diff --git a/src/language-js/parser-babel.js b/src/language-js/parser-babel.js
index 8f43d5af634d..982bfc925ba6 100644
--- a/src/language-js/parser-babel.js
+++ b/src/language-js/parser-babel.js
@@ -35,7 +35,7 @@ function babelOptions({ sourceType, extraPlugins = [] }) {
       "partialApplication",
       ["decorators", { decoratorsBeforeExport: false }],
       "privateIn",
-      ["moduleAttributes", { version: "may-2020" }],
+      "importAssertions",
       ["recordAndTuple", { syntaxType: "hash" }],
       "decimal",
       ...extraPlugins,
diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index 6d0d8c8b356b..0e97df0a9ac9 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -875,8 +875,12 @@ function printPathNoParens(path, options, print, args) {
         parts.push(" ", path.call(print, "source"));
       }
 
-      if (Array.isArray(n.attributes) && n.attributes.length !== 0) {
-        parts.push(" with ", concat(path.map(print, "attributes")));
+      if (Array.isArray(n.assertions) && n.assertions.length !== 0) {
+        parts.push(
+          " assert { ",
+          join(", ", path.map(print, "assertions")),
+          " }"
+        );
       }
 
       parts.push(semi);
diff --git a/tests/js/babel-plugins/__snapshots__/jsfmt.spec.js.snap b/tests/js/babel-plugins/__snapshots__/jsfmt.spec.js.snap
index ce07e8eafb2c..ad2930a691af 100644
--- a/tests/js/babel-plugins/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/js/babel-plugins/__snapshots__/jsfmt.spec.js.snap
@@ -683,6 +683,34 @@ iterator.next(2); // Logs "Yield 2"
 ================================================================================
 `;
 
+exports[`import-assertions-dynamic.js format 1`] = `
+====================================options=====================================
+parsers: ["babel", "babel-ts", "babel-flow"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+import("./foo.json", { assert: { type: "json" } });
+
+=====================================output=====================================
+import("./foo.json", { assert: { type: "json" } });
+
+================================================================================
+`;
+
+exports[`import-assertions-static.js format 1`] = `
+====================================options=====================================
+parsers: ["babel", "babel-ts", "babel-flow"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+import json from "./foo.json" assert { type: "json" };
+
+=====================================output=====================================
+import json from "./foo.json" assert { type: "json" };
+
+================================================================================
+`;
+
 exports[`import-meta.js format 1`] = `
 ====================================options=====================================
 parsers: ["babel", "babel-ts", "babel-flow"]
@@ -783,34 +811,6 @@ obj.a.b &&= c;
 ================================================================================
 `;
 
-exports[`module-attributes-dynamic.js format 1`] = `
-====================================options=====================================
-parsers: ["babel", "babel-ts", "babel-flow"]
-printWidth: 80
-                                                                                | printWidth
-=====================================input======================================
-import("foo.json", { with: { type: "json" } })
-
-=====================================output=====================================
-import("foo.json", { with: { type: "json" } });
-
-================================================================================
-`;
-
-exports[`module-attributes-static.js format 1`] = `
-====================================options=====================================
-parsers: ["babel", "babel-ts", "babel-flow"]
-printWidth: 80
-                                                                                | printWidth
-=====================================input======================================
-import foo from "foo.json" with type: "json";
-
-=====================================output=====================================
-import foo from "foo.json" with type: "json";
-
-================================================================================
-`;
-
 exports[`nullish-coalescing-operator.js format 1`] = `
 ====================================options=====================================
 parsers: ["babel", "babel-ts", "babel-flow"]
diff --git a/tests/js/babel-plugins/import-assertions-dynamic.js b/tests/js/babel-plugins/import-assertions-dynamic.js
new file mode 100644
index 000000000000..2411a524bf12
--- /dev/null
+++ b/tests/js/babel-plugins/import-assertions-dynamic.js
@@ -0,0 +1 @@
+import("./foo.json", { assert: { type: "json" } });
diff --git a/tests/js/babel-plugins/import-assertions-static.js b/tests/js/babel-plugins/import-assertions-static.js
new file mode 100644
index 000000000000..890e4290079e
--- /dev/null
+++ b/tests/js/babel-plugins/import-assertions-static.js
@@ -0,0 +1 @@
+import json from "./foo.json" assert { type: "json" };
diff --git a/tests/js/babel-plugins/jsfmt.spec.js b/tests/js/babel-plugins/jsfmt.spec.js
index 40fa5ab94930..b85bc01d31bb 100644
--- a/tests/js/babel-plugins/jsfmt.spec.js
+++ b/tests/js/babel-plugins/jsfmt.spec.js
@@ -12,8 +12,8 @@ run_spec(__dirname, ["babel", "babel-ts", "babel-flow"], {
       "flow.js",
       "function-bind.js",
       "function-sent.js",
-      "module-attributes-dynamic.js",
-      "module-attributes-static.js",
+      "import-assertions-dynamic.js",
+      "import-assertions-static.js",
       "partial-application.js",
       "pipeline-operator-fsharp.js",
       "pipeline-operator-minimal.js",
diff --git a/tests/js/babel-plugins/module-attributes-dynamic.js b/tests/js/babel-plugins/module-attributes-dynamic.js
deleted file mode 100644
index baa60fc43c5f..000000000000
--- a/tests/js/babel-plugins/module-attributes-dynamic.js
+++ /dev/null
@@ -1 +0,0 @@
-import("foo.json", { with: { type: "json" } })
diff --git a/tests/js/babel-plugins/module-attributes-static.js b/tests/js/babel-plugins/module-attributes-static.js
deleted file mode 100644
index fb31508a0860..000000000000
--- a/tests/js/babel-plugins/module-attributes-static.js
+++ /dev/null
@@ -1 +0,0 @@
-import foo from "foo.json" with type: "json";
diff --git a/tests/js/import-assertions/__snapshots__/jsfmt.spec.js.snap b/tests/js/import-assertions/__snapshots__/jsfmt.spec.js.snap
new file mode 100644
index 000000000000..a2e60e8ccf73
--- /dev/null
+++ b/tests/js/import-assertions/__snapshots__/jsfmt.spec.js.snap
@@ -0,0 +1,43 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`import-assertions-dynamic.js format 1`] = `
+====================================options=====================================
+parsers: ["babel"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+import("./foo.json", { assert: { type: "json" } });
+
+=====================================output=====================================
+import("./foo.json", { assert: { type: "json" } });
+
+================================================================================
+`;
+
+exports[`import-assertions-multi-types.js format 1`] = `
+====================================options=====================================
+parsers: ["babel"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+import json from "./foo.json" assert { type: "json", type: "bar" };
+
+=====================================output=====================================
+import json from "./foo.json" assert { type: "json", type: "bar" };
+
+================================================================================
+`;
+
+exports[`import-assertions-static.js format 1`] = `
+====================================options=====================================
+parsers: ["babel"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+import json from "./foo.json" assert { type: "json" };
+
+=====================================output=====================================
+import json from "./foo.json" assert { type: "json" };
+
+================================================================================
+`;
diff --git a/tests/js/import-assertions/import-assertions-dynamic.js b/tests/js/import-assertions/import-assertions-dynamic.js
new file mode 100644
index 000000000000..2411a524bf12
--- /dev/null
+++ b/tests/js/import-assertions/import-assertions-dynamic.js
@@ -0,0 +1 @@
+import("./foo.json", { assert: { type: "json" } });
diff --git a/tests/js/import-assertions/import-assertions-multi-types.js b/tests/js/import-assertions/import-assertions-multi-types.js
new file mode 100644
index 000000000000..3afaa0d2b7cd
--- /dev/null
+++ b/tests/js/import-assertions/import-assertions-multi-types.js
@@ -0,0 +1 @@
+import json from "./foo.json" assert { type: "json", type: "bar" };
diff --git a/tests/js/import-assertions/import-assertions-static.js b/tests/js/import-assertions/import-assertions-static.js
new file mode 100644
index 000000000000..890e4290079e
--- /dev/null
+++ b/tests/js/import-assertions/import-assertions-static.js
@@ -0,0 +1 @@
+import json from "./foo.json" assert { type: "json" };
diff --git a/tests/js/module-attributes/jsfmt.spec.js b/tests/js/import-assertions/jsfmt.spec.js
similarity index 100%
rename from tests/js/module-attributes/jsfmt.spec.js
rename to tests/js/import-assertions/jsfmt.spec.js
diff --git a/tests/js/module-attributes/__snapshots__/jsfmt.spec.js.snap b/tests/js/module-attributes/__snapshots__/jsfmt.spec.js.snap
deleted file mode 100644
index 43233aa6c419..000000000000
--- a/tests/js/module-attributes/__snapshots__/jsfmt.spec.js.snap
+++ /dev/null
@@ -1,29 +0,0 @@
-// Jest Snapshot v1, https://goo.gl/fbAQLP
-
-exports[`module-attributes-dynamic.js format 1`] = `
-====================================options=====================================
-parsers: ["babel"]
-printWidth: 80
-                                                                                | printWidth
-=====================================input======================================
-import("foo.json", { with: { type: "json" } })
-
-=====================================output=====================================
-import("foo.json", { with: { type: "json" } });
-
-================================================================================
-`;
-
-exports[`module-attributes-static.js format 1`] = `
-====================================options=====================================
-parsers: ["babel"]
-printWidth: 80
-                                                                                | printWidth
-=====================================input======================================
-import foo from "foo.json" with type: "json";
-
-=====================================output=====================================
-import foo from "foo.json" with type: "json";
-
-================================================================================
-`;
diff --git a/tests/js/module-attributes/module-attributes-dynamic.js b/tests/js/module-attributes/module-attributes-dynamic.js
deleted file mode 100644
index baa60fc43c5f..000000000000
--- a/tests/js/module-attributes/module-attributes-dynamic.js
+++ /dev/null
@@ -1 +0,0 @@
-import("foo.json", { with: { type: "json" } })
diff --git a/tests/js/module-attributes/module-attributes-static.js b/tests/js/module-attributes/module-attributes-static.js
deleted file mode 100644
index fb31508a0860..000000000000
--- a/tests/js/module-attributes/module-attributes-static.js
+++ /dev/null
@@ -1 +0,0 @@
-import foo from "foo.json" with type: "json";

From 26ec800e5439fa8d58bd6afe68b4a578933cd421 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Sun, 18 Oct 2020 21:03:22 +0900
Subject: [PATCH 14/25] Support "String import/export specifier"

---
 src/language-js/parser-babel.js               |  1 +
 src/language-js/printer-estree.js             | 11 +++++--
 .../__snapshots__/jsfmt.spec.js.snap          | 14 +++++++++
 tests/js/babel-plugins/jsfmt.spec.js          |  1 +
 tests/js/babel-plugins/module-string-names.js |  1 +
 .../__snapshots__/jsfmt.spec.js.snap          | 30 +++++++++++++++++++
 tests/js/module-string-names/jsfmt.spec.js    |  1 +
 .../module-string-names.js                    |  7 +++++
 8 files changed, 64 insertions(+), 2 deletions(-)
 create mode 100644 tests/js/babel-plugins/module-string-names.js
 create mode 100644 tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap
 create mode 100644 tests/js/module-string-names/jsfmt.spec.js
 create mode 100644 tests/js/module-string-names/module-string-names.js

diff --git a/src/language-js/parser-babel.js b/src/language-js/parser-babel.js
index 982bfc925ba6..2685fbf5fd73 100644
--- a/src/language-js/parser-babel.js
+++ b/src/language-js/parser-babel.js
@@ -38,6 +38,7 @@ function babelOptions({ sourceType, extraPlugins = [] }) {
       "importAssertions",
       ["recordAndTuple", { syntaxType: "hash" }],
       "decimal",
+      "moduleStringNames",
       ...extraPlugins,
     ],
     tokens: true,
diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index 0e97df0a9ac9..1e5b182ca0be 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -808,14 +808,21 @@ function printPathNoParens(path, options, print, args) {
       }
 
       return concat(parts);
-    case "ExportSpecifier":
+    case "ExportSpecifier": {
       parts.push(path.call(print, "local"));
 
-      if (n.exported && n.exported.name !== n.local.name) {
+      const { exported, local } = n;
+      if (
+        exported &&
+        (exported.type !== local.type ||
+          (exported.type === "Identifier" && exported.name !== local.name) ||
+          (exported.type === "StringLiteral" && exported.value !== local.value))
+      ) {
         parts.push(" as ", path.call(print, "exported"));
       }
 
       return concat(parts);
+    }
     case "ImportNamespaceSpecifier":
       parts.push("* as ");
       parts.push(path.call(print, "local"));
diff --git a/tests/js/babel-plugins/__snapshots__/jsfmt.spec.js.snap b/tests/js/babel-plugins/__snapshots__/jsfmt.spec.js.snap
index ad2930a691af..3fb0f223cc0f 100644
--- a/tests/js/babel-plugins/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/js/babel-plugins/__snapshots__/jsfmt.spec.js.snap
@@ -811,6 +811,20 @@ obj.a.b &&= c;
 ================================================================================
 `;
 
+exports[`module-string-names.js format 1`] = `
+====================================options=====================================
+parsers: ["babel", "babel-ts", "babel-flow"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+export { smile as "😄" } from "./emojis.js";
+
+=====================================output=====================================
+export { smile as "😄" } from "./emojis.js";
+
+================================================================================
+`;
+
 exports[`nullish-coalescing-operator.js format 1`] = `
 ====================================options=====================================
 parsers: ["babel", "babel-ts", "babel-flow"]
diff --git a/tests/js/babel-plugins/jsfmt.spec.js b/tests/js/babel-plugins/jsfmt.spec.js
index b85bc01d31bb..35b39843d803 100644
--- a/tests/js/babel-plugins/jsfmt.spec.js
+++ b/tests/js/babel-plugins/jsfmt.spec.js
@@ -26,6 +26,7 @@ run_spec(__dirname, ["babel", "babel-ts", "babel-flow"], {
       "typescript.js",
       "v8intrinsic.js",
       "optional-chaining.js",
+      "module-string-names.js",
     ],
   },
 });
diff --git a/tests/js/babel-plugins/module-string-names.js b/tests/js/babel-plugins/module-string-names.js
new file mode 100644
index 000000000000..631c04f79793
--- /dev/null
+++ b/tests/js/babel-plugins/module-string-names.js
@@ -0,0 +1 @@
+export { smile as "😄" } from "./emojis.js";
diff --git a/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap b/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap
new file mode 100644
index 000000000000..75ffa47105f2
--- /dev/null
+++ b/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap
@@ -0,0 +1,30 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`module-string-names.js format 1`] = `
+====================================options=====================================
+parsers: ["babel"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+export { smile as "smile" } from "./emojis.js";
+export { "smile" as smile } from "./emojis.js";
+export { "smile" as "smile" } from "./emojis.js";
+export { foo, bar as "foo" } from "./emojis.js";
+export { foo, bar as "foo" };
+export { "學而時習之，不亦說乎？", "吾道一以貫之。" as "忠恕。" } from "Confucius";
+export * as "foo", { default as "quux" } from "module-b";
+
+=====================================output=====================================
+export { smile as "smile" } from "./emojis.js";
+export { "smile" as smile } from "./emojis.js";
+export { "smile" } from "./emojis.js";
+export { foo, bar as "foo" } from "./emojis.js";
+export { foo, bar as "foo" };
+export {
+  "學而時習之，不亦說乎？",
+  "吾道一以貫之。" as "忠恕。",
+} from "Confucius";
+export * as "foo", { default as "quux" } from "module-b";
+
+================================================================================
+`;
diff --git a/tests/js/module-string-names/jsfmt.spec.js b/tests/js/module-string-names/jsfmt.spec.js
new file mode 100644
index 000000000000..726eaec01590
--- /dev/null
+++ b/tests/js/module-string-names/jsfmt.spec.js
@@ -0,0 +1 @@
+run_spec(__dirname, ["babel"], { errors: { espree: true } });
diff --git a/tests/js/module-string-names/module-string-names.js b/tests/js/module-string-names/module-string-names.js
new file mode 100644
index 000000000000..e4a2a1e79a17
--- /dev/null
+++ b/tests/js/module-string-names/module-string-names.js
@@ -0,0 +1,7 @@
+export { smile as "smile" } from "./emojis.js";
+export { "smile" as smile } from "./emojis.js";
+export { "smile" as "smile" } from "./emojis.js";
+export { foo, bar as "foo" } from "./emojis.js";
+export { foo, bar as "foo" };
+export { "學而時習之，不亦說乎？", "吾道一以貫之。" as "忠恕。" } from "Confucius";
+export * as "foo", { default as "quux" } from "module-b";

From ac9f5583cbd388b4c4863f472e6a9ed15afa0e77 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Sun, 18 Oct 2020 21:31:13 +0900
Subject: [PATCH 15/25] Remove tests for module-attributes

---
 tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap | 7 -------
 tests/misc/errors/js/module-attributes.js             | 1 -
 2 files changed, 8 deletions(-)
 delete mode 100644 tests/misc/errors/js/module-attributes.js

diff --git a/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap b/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
index 02535f581236..8985c5fa7a9d 100644
--- a/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
@@ -11,13 +11,6 @@ exports[`html-like-comments.js error test 1`] = `
   6 | "
 `;
 
-exports[`module-attributes.js error test 1`] = `
-"The only accepted module attribute is \`type\` (1:33)
-> 1 | import foo from \\"foo.json\\" with foo: \\"json\\";
-    |                                 ^
-  2 | "
-`;
-
 exports[`no-for-in-init-concise-binary-in.js error test 1`] = `
 "Unexpected token, expected \\")\\" (3:18)
   1 | // https://github.com/babel/babel/pull/11931
diff --git a/tests/misc/errors/js/module-attributes.js b/tests/misc/errors/js/module-attributes.js
deleted file mode 100644
index ecc33f5eb941..000000000000
--- a/tests/misc/errors/js/module-attributes.js
+++ /dev/null
@@ -1 +0,0 @@
-import foo from "foo.json" with foo: "json";

From 71128fed5a12259df4bd9d9c2179d4a28ef10447 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Mon, 19 Oct 2020 10:22:43 +0900
Subject: [PATCH 16/25] Add changelog

---
 changelog_unreleased/javascript/pr-9408.md | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 changelog_unreleased/javascript/pr-9408.md

diff --git a/changelog_unreleased/javascript/pr-9408.md b/changelog_unreleased/javascript/pr-9408.md
new file mode 100644
index 000000000000..a1cac18b412b
--- /dev/null
+++ b/changelog_unreleased/javascript/pr-9408.md
@@ -0,0 +1,21 @@
+#### Update to `@babel/parser` 7.12
+
+Updated the JavaScript parser to [`@babel/parser` 7.12](https://babeljs.io/blog/2020/10/15/7.12.0). This fixes several bugs and supports some new syntax.
+
+##### Support Import Assertions
+
+[The "module attributes" proposal supported on 2.1](https://prettier.io/blog/2020/08/24/2.1.0.html#support-es-module-attributes-and-json-modules-8436httpsgithubcomprettierprettierpull8436-by-fiskerhttpsgithubcomfisker) has been significantly changed and also renamed to "import assertions".
+
+```js
+import json from "./foo.json" assert { type: "json" };
+```
+
+##### Support imports and exports with string names
+
+<!-- TODO: Remove if the bug is fixed -->
+Due to a [bug in `@babel/parser`](https://github.com/babel/babel/issues/12209), Prettier can only use exports, but that will be fixed.
+
+```js
+let happy = "wooo!";
+export { happy as "😃" };
+```

From 766c4cf45f05c604d6333e687cdc630de2776d18 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Mon, 19 Oct 2020 10:26:54 +0900
Subject: [PATCH 17/25] Update to 7.12.3

---
 package.json                                        |  2 +-
 .../babel-ts/__snapshots__/jsfmt.spec.js.snap       | 13 ++++++++++---
 .../babel-ts/type-annotation-expr-statement.ts      |  1 +
 .../{type-annotation.ts => type-annotation-func.ts} |  0
 yarn.lock                                           |  8 ++++----
 5 files changed, 16 insertions(+), 8 deletions(-)
 create mode 100644 tests/misc/errors/babel-ts/type-annotation-expr-statement.ts
 rename tests/misc/errors/babel-ts/{type-annotation.ts => type-annotation-func.ts} (100%)

diff --git a/package.json b/package.json
index b1924a94f4c8..b17d5d25a085 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
   "dependencies": {
     "@angular/compiler": "10.1.6",
     "@babel/code-frame": "7.10.4",
-    "@babel/parser": "7.12.0",
+    "@babel/parser": "7.12.3",
     "@glimmer/syntax": "0.62.3",
     "@iarna/toml": "2.2.5",
     "@typescript-eslint/typescript-estree": "3.10.1",
diff --git a/tests/misc/errors/babel-ts/__snapshots__/jsfmt.spec.js.snap b/tests/misc/errors/babel-ts/__snapshots__/jsfmt.spec.js.snap
index 6d96116982a4..63d4dde0ac58 100644
--- a/tests/misc/errors/babel-ts/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/misc/errors/babel-ts/__snapshots__/jsfmt.spec.js.snap
@@ -1,8 +1,15 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`type-annotation.ts error test 1`] = `
-"Did not expect a type annotation here. (1:9)
+exports[`type-annotation-expr-statement.ts error test 1`] = `
+"Did not expect a type annotation here. (1:3)
+> 1 | (a: T);
+    |   ^
+  2 | "
+`;
+
+exports[`type-annotation-func.ts error test 1`] = `
+"Did not expect a type annotation here. (1:10)
 > 1 | func<T>(a: T);
-    |         ^
+    |          ^
   2 | "
 `;
diff --git a/tests/misc/errors/babel-ts/type-annotation-expr-statement.ts b/tests/misc/errors/babel-ts/type-annotation-expr-statement.ts
new file mode 100644
index 000000000000..25f14e1b9984
--- /dev/null
+++ b/tests/misc/errors/babel-ts/type-annotation-expr-statement.ts
@@ -0,0 +1 @@
+(a: T);
diff --git a/tests/misc/errors/babel-ts/type-annotation.ts b/tests/misc/errors/babel-ts/type-annotation-func.ts
similarity index 100%
rename from tests/misc/errors/babel-ts/type-annotation.ts
rename to tests/misc/errors/babel-ts/type-annotation-func.ts
diff --git a/yarn.lock b/yarn.lock
index 0e406597c4ad..cb866837ff3f 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -277,10 +277,10 @@
     chalk "^2.0.0"
     js-tokens "^4.0.0"
 
-"@babel/parser@7.12.0":
-  version "7.12.0"
-  resolved "https://registry.yarnpkg.com/@babel/parser/-/parser-7.12.0.tgz#2ad388f3960045b22f9b7d4bf85e80b15a1c9e3a"
-  integrity sha512-dYmySMYnlus2jwl7JnnajAj11obRStZoW9cG04wh4ZuhozDn11tDUrhHcUZ9iuNHqALAhh60XqNaYXpvuuE/Gg==
+"@babel/parser@7.12.3":
+  version "7.12.3"
+  resolved "https://registry.yarnpkg.com/@babel/parser/-/parser-7.12.3.tgz#a305415ebe7a6c7023b40b5122a0662d928334cd"
+  integrity sha512-kFsOS0IbsuhO5ojF8Hc8z/8vEIOkylVBrjiZUbLTE3XFe0Qi+uu6HjzQixkFaqr0ZPAMZcBVxEwmsnsLPZ2Xsw==
 
 "@babel/parser@^7.1.0", "@babel/parser@^7.10.4", "@babel/parser@^7.12.1", "@babel/parser@^7.7.0":
   version "7.12.1"

From c06180e968575531c9df9d826c63338747fda2cc Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Mon, 19 Oct 2020 10:28:19 +0900
Subject: [PATCH 18/25] Fix by linter

---
 changelog_unreleased/javascript/pr-9408.md | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/changelog_unreleased/javascript/pr-9408.md b/changelog_unreleased/javascript/pr-9408.md
index a1cac18b412b..5e634735f8a7 100644
--- a/changelog_unreleased/javascript/pr-9408.md
+++ b/changelog_unreleased/javascript/pr-9408.md
@@ -1,4 +1,4 @@
-#### Update to `@babel/parser` 7.12
+#### Update to `@babel/parser` 7.12 (#9408 by @sosukesuzuki)
 
 Updated the JavaScript parser to [`@babel/parser` 7.12](https://babeljs.io/blog/2020/10/15/7.12.0). This fixes several bugs and supports some new syntax.
 
@@ -13,6 +13,7 @@ import json from "./foo.json" assert { type: "json" };
 ##### Support imports and exports with string names
 
 <!-- TODO: Remove if the bug is fixed -->
+
 Due to a [bug in `@babel/parser`](https://github.com/babel/babel/issues/12209), Prettier can only use exports, but that will be fixed.
 
 ```js

From b1558d197b0626c5a658cbdac75d87848d0a8a1d Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Mon, 19 Oct 2020 10:32:15 +0900
Subject: [PATCH 19/25] Fix by spellchecker

---
 changelog_unreleased/javascript/pr-9408.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/changelog_unreleased/javascript/pr-9408.md b/changelog_unreleased/javascript/pr-9408.md
index 5e634735f8a7..c1503f46d3e0 100644
--- a/changelog_unreleased/javascript/pr-9408.md
+++ b/changelog_unreleased/javascript/pr-9408.md
@@ -17,6 +17,6 @@ import json from "./foo.json" assert { type: "json" };
 Due to a [bug in `@babel/parser`](https://github.com/babel/babel/issues/12209), Prettier can only use exports, but that will be fixed.
 
 ```js
-let happy = "wooo!";
+let happy = "happy";
 export { happy as "😃" };
 ```

From 645200833b90119477ed256cb2108ea374327b88 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Mon, 19 Oct 2020 11:47:49 +0900
Subject: [PATCH 20/25] Add tests for module attributes to errors

---
 tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap | 7 +++++++
 tests/misc/errors/js/module-attributes.js             | 1 +
 2 files changed, 8 insertions(+)
 create mode 100644 tests/misc/errors/js/module-attributes.js

diff --git a/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap b/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
index 8985c5fa7a9d..7c032898bcb4 100644
--- a/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
@@ -11,6 +11,13 @@ exports[`html-like-comments.js error test 1`] = `
   6 | "
 `;
 
+exports[`module-attributes.js error test 1`] = `
+"Unexpected token, expected \\";\\" (1:28)
+> 1 | import foo from \\"foo.json\\" with type: \\"json\\";
+    |                            ^
+  2 | "
+`;
+
 exports[`no-for-in-init-concise-binary-in.js error test 1`] = `
 "Unexpected token, expected \\")\\" (3:18)
   1 | // https://github.com/babel/babel/pull/11931
diff --git a/tests/misc/errors/js/module-attributes.js b/tests/misc/errors/js/module-attributes.js
new file mode 100644
index 000000000000..fb31508a0860
--- /dev/null
+++ b/tests/misc/errors/js/module-attributes.js
@@ -0,0 +1 @@
+import foo from "foo.json" with type: "json";

From f1182e7c927d6ba85dc9d25ffe46cb2cfc507167 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Mon, 19 Oct 2020 12:17:41 +0900
Subject: [PATCH 21/25] Add error test for module string name with import

---
 tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap | 8 ++++++++
 tests/misc/errors/js/module-string-name-import.js     | 2 ++
 2 files changed, 10 insertions(+)
 create mode 100644 tests/misc/errors/js/module-string-name-import.js

diff --git a/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap b/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
index 7c032898bcb4..beea9da8ccba 100644
--- a/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
@@ -18,6 +18,14 @@ exports[`module-attributes.js error test 1`] = `
   2 | "
 `;
 
+exports[`module-string-name-import.js error test 1`] = `
+"Unexpected token (2:10)
+  1 | // https://github.com/babel/babel/issues/12209
+> 2 | import { \\"foo\\" as foo } from \\"module-a\\";
+    |          ^
+  3 | "
+`;
+
 exports[`no-for-in-init-concise-binary-in.js error test 1`] = `
 "Unexpected token, expected \\")\\" (3:18)
   1 | // https://github.com/babel/babel/pull/11931
diff --git a/tests/misc/errors/js/module-string-name-import.js b/tests/misc/errors/js/module-string-name-import.js
new file mode 100644
index 000000000000..53167a0d5443
--- /dev/null
+++ b/tests/misc/errors/js/module-string-name-import.js
@@ -0,0 +1,2 @@
+// https://github.com/babel/babel/issues/12209
+import { "foo" as foo } from "module-a";

From 226b1dbe79050d35db09a127b13124cadca8d11a Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Mon, 19 Oct 2020 18:59:55 +0900
Subject: [PATCH 22/25] Remove TSTypeCastExpression

---
 src/language-js/printer-estree.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index 1e5b182ca0be..491ef8375087 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -2898,8 +2898,7 @@ function printPathNoParens(path, options, print, args) {
 
       return group(concat(parts));
     }
-    case "TypeCastExpression":
-    case "TSTypeCastExpression": {
+    case "TypeCastExpression": {
       return concat([
         "(",
         path.call(print, "expression"),

From bc5251de62d01d8140b3ef0fcb59c874c60834e5 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Tue, 20 Oct 2020 03:02:25 +0900
Subject: [PATCH 23/25] Add tests for funny import-assertions

---
 .../__snapshots__/jsfmt.spec.js.snap             | 16 ++++++++++++++++
 tests/js/import-assertions/jsfmt.spec.js         | 10 +++++++++-
 .../import-assertions/not-import-assertions.js   |  2 ++
 .../errors/js/__snapshots__/jsfmt.spec.js.snap   |  7 +++++++
 .../errors/js/import-assertions-with-parens.js   |  1 +
 5 files changed, 35 insertions(+), 1 deletion(-)
 create mode 100644 tests/js/import-assertions/not-import-assertions.js
 create mode 100644 tests/misc/errors/js/import-assertions-with-parens.js

diff --git a/tests/js/import-assertions/__snapshots__/jsfmt.spec.js.snap b/tests/js/import-assertions/__snapshots__/jsfmt.spec.js.snap
index a2e60e8ccf73..df01ffc7403d 100644
--- a/tests/js/import-assertions/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/js/import-assertions/__snapshots__/jsfmt.spec.js.snap
@@ -41,3 +41,19 @@ import json from "./foo.json" assert { type: "json" };
 
 ================================================================================
 `;
+
+exports[`not-import-assertions.js format 1`] = `
+====================================options=====================================
+parsers: ["babel"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+import "x"
+assert ({type: 'json'});
+
+=====================================output=====================================
+import "x";
+assert({ type: "json" });
+
+================================================================================
+`;
diff --git a/tests/js/import-assertions/jsfmt.spec.js b/tests/js/import-assertions/jsfmt.spec.js
index 726eaec01590..c3095e9d8d7f 100644
--- a/tests/js/import-assertions/jsfmt.spec.js
+++ b/tests/js/import-assertions/jsfmt.spec.js
@@ -1 +1,9 @@
-run_spec(__dirname, ["babel"], { errors: { espree: true } });
+run_spec(__dirname, ["babel"], {
+  errors: {
+    espree: [
+      "import-assertions-dynamic.js",
+      "import-assertions-multi-types.js",
+      "import-assertions-static.js",
+    ],
+  },
+});
diff --git a/tests/js/import-assertions/not-import-assertions.js b/tests/js/import-assertions/not-import-assertions.js
new file mode 100644
index 000000000000..e6461bad63c5
--- /dev/null
+++ b/tests/js/import-assertions/not-import-assertions.js
@@ -0,0 +1,2 @@
+import "x"
+assert ({type: 'json'});
diff --git a/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap b/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
index beea9da8ccba..5354a8b1c146 100644
--- a/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/misc/errors/js/__snapshots__/jsfmt.spec.js.snap
@@ -11,6 +11,13 @@ exports[`html-like-comments.js error test 1`] = `
   6 | "
 `;
 
+exports[`import-assertions-with-parens.js error test 1`] = `
+"Unexpected token (1:19)
+> 1 | import \\"x\\" assert ({type: 'json'});
+    |                   ^
+  2 | "
+`;
+
 exports[`module-attributes.js error test 1`] = `
 "Unexpected token, expected \\";\\" (1:28)
 > 1 | import foo from \\"foo.json\\" with type: \\"json\\";
diff --git a/tests/misc/errors/js/import-assertions-with-parens.js b/tests/misc/errors/js/import-assertions-with-parens.js
new file mode 100644
index 000000000000..f20676b37cb0
--- /dev/null
+++ b/tests/misc/errors/js/import-assertions-with-parens.js
@@ -0,0 +1 @@
+import "x" assert ({type: 'json'});

From 7042f57400fe01c8cc01dd16d97be463a58ded96 Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Tue, 20 Oct 2020 17:22:33 +0900
Subject: [PATCH 24/25] Update snapshots|

---
 tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap b/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap
index 75ffa47105f2..ae069d276f1f 100644
--- a/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap
@@ -17,7 +17,7 @@ export * as "foo", { default as "quux" } from "module-b";
 =====================================output=====================================
 export { smile as "smile" } from "./emojis.js";
 export { "smile" as smile } from "./emojis.js";
-export { "smile" } from "./emojis.js";
+export { "smile" as "smile" } from "./emojis.js";
 export { foo, bar as "foo" } from "./emojis.js";
 export { foo, bar as "foo" };
 export {

From aaa7326b68aabb4afd1dd72893cacb809644b90e Mon Sep 17 00:00:00 2001
From: sosukesuzuki <aosukeke@gmail.com>
Date: Tue, 20 Oct 2020 18:17:13 +0900
Subject: [PATCH 25/25] Add more tests

---
 tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap | 2 ++
 tests/js/module-string-names/module-string-names.js           | 1 +
 2 files changed, 3 insertions(+)

diff --git a/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap b/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap
index ae069d276f1f..b2f9e1c02d49 100644
--- a/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/js/module-string-names/__snapshots__/jsfmt.spec.js.snap
@@ -13,6 +13,7 @@ export { foo, bar as "foo" } from "./emojis.js";
 export { foo, bar as "foo" };
 export { "學而時習之，不亦說乎？", "吾道一以貫之。" as "忠恕。" } from "Confucius";
 export * as "foo", { default as "quux" } from "module-b";
+export { "smile" } from "./emojis.js";
 
 =====================================output=====================================
 export { smile as "smile" } from "./emojis.js";
@@ -25,6 +26,7 @@ export {
   "吾道一以貫之。" as "忠恕。",
 } from "Confucius";
 export * as "foo", { default as "quux" } from "module-b";
+export { "smile" } from "./emojis.js";
 
 ================================================================================
 `;
diff --git a/tests/js/module-string-names/module-string-names.js b/tests/js/module-string-names/module-string-names.js
index e4a2a1e79a17..cab6023a156e 100644
--- a/tests/js/module-string-names/module-string-names.js
+++ b/tests/js/module-string-names/module-string-names.js
@@ -5,3 +5,4 @@ export { foo, bar as "foo" } from "./emojis.js";
 export { foo, bar as "foo" };
 export { "學而時習之，不亦說乎？", "吾道一以貫之。" as "忠恕。" } from "Confucius";
 export * as "foo", { default as "quux" } from "module-b";
+export { "smile" } from "./emojis.js";