forked from babel/babel
/
scope.js
1005 lines (909 loc) · 33.7 KB
/
scope.js
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import { parse } from "@babel/parser";
import * as t from "@babel/types";
import _traverse, { NodePath } from "../lib/index.js";
const traverse = _traverse.default || _traverse;
function getPath(code, options) {
const ast =
typeof code === "string" ? parse(code, options) : createNode(code);
let path;
traverse(ast, {
Program: function (_path) {
path = _path;
_path.stop();
},
});
return path;
}
function getIdentifierPath(code) {
const ast = parse(code);
let nodePath;
traverse(ast, {
Identifier: function (path) {
nodePath = path;
path.stop();
},
});
return nodePath;
}
function createNode(node) {
const ast = t.file(t.program(Array.isArray(node) ? node : [node]));
// This puts the path into the cache internally
// We afterwards traverse ast, as we need to start traversing
// at the File node and not the Program node
NodePath.get({
hub: {
buildError: (_, msg) => new Error(msg),
},
parentPath: null,
parent: ast,
container: ast,
key: "program",
}).setContext();
return ast;
}
describe("scope", () => {
describe("binding paths", () => {
it("function declaration id", function () {
expect(
getPath("function foo() {}").scope.getBinding("foo").path.type,
).toBe("FunctionDeclaration");
});
it("function expression id", function () {
expect(
getPath("(function foo() {})")
.get("body")[0]
.get("expression")
.scope.getBinding("foo").path.type,
).toBe("FunctionExpression");
});
it("function param", function () {
expect(
getPath("(function (foo) {})")
.get("body")[0]
.get("expression")
.scope.getBinding("foo").path.type,
).toBe("Identifier");
});
describe("function parameter expression", function () {
it("should not have visibility of declarations inside function body", () => {
expect(
getPath(
`var a = "outside"; (function foo(b = a) { let a = "inside" })`,
)
.get("body.1.expression.params.0")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
});
it("should have visibility on parameter bindings", () => {
expect(
getPath(`var a = "outside"; (function foo(b = a, a = "inside") {})`)
.get("body.1.expression.params.0")
.scope.getBinding("a").path.node.right.value,
).toBe("inside");
});
});
describe("import declaration", () => {
it.each([
[
"import default",
"import foo from 'foo';(foo)=>{}",
"foo",
"ImportDefaultSpecifier",
],
[
"import named default",
"import { default as foo } from 'foo';(foo)=>{}",
"foo",
"ImportSpecifier",
],
[
"import named",
"import { foo } from 'foo';(foo)=>{}",
"foo",
"ImportSpecifier",
],
[
"import named aliased",
"import { _foo as foo } from 'foo';(foo)=>{}",
"foo",
"ImportSpecifier",
],
[
"import namespace",
"import * as foo from 'foo';(foo)=>{}",
"foo",
"ImportNamespaceSpecifier",
],
])("%s", (testTitle, source, bindingName, bindingNodeType) => {
expect(
getPath(source, { sourceType: "module" }).scope.getBinding(
bindingName,
).path.type,
).toBe(bindingNodeType);
});
});
describe("export declaration", () => {
it.each([
[
"export default function",
"export default function foo(foo) {}",
"foo",
"FunctionDeclaration",
],
[
"export default class",
"export default class foo extends function foo () {} {}",
"foo",
"ClassDeclaration",
],
[
"export named default",
"export const foo = function foo(foo) {};",
"foo",
"VariableDeclarator",
],
[
"export named default",
"export const [ { foo } ] = function foo(foo) {};",
"foo",
"VariableDeclarator",
],
])("%s", (testTitle, source, bindingName, bindingNodeType) => {
expect(
getPath(source, { sourceType: "module" }).scope.getBinding(
bindingName,
).path.type,
).toBe(bindingNodeType);
});
});
describe("computed method key", () => {
describe("should not have visibility of declarations inside method body", () => {
it("when path is computed key", () => {
expect(
getPath(`var a = "outside"; ({ [a]() { let a = "inside" } })`)
.get("body.1.expression.properties.0.key")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
expect(
getPath(
`var a = "outside"; class foo { [a]() { let a = "inside" } }`,
)
.get("body.1.body.body.0.key")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
});
it("when path is in nested scope which is computed key", () => {
expect(
getPath(`var a = "outside"; ({ [() => a]() { let a = "inside" } })`)
.get("body.1.expression.properties.0.key.body")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
expect(
getPath(
`var a = "outside"; class foo { [() => a]() { let a = "inside" } }`,
)
.get("body.1.body.body.0.key.body")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
});
it("when path is in nested scope within computed key", () => {
expect(
getPath(
`var a = "outside"; ({ [(() => a)() + ""]() { let a = "inside" } })`,
)
.get("body.1.expression.properties.0.key.left.callee.body")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
expect(
getPath(
`var a = "outside"; class foo { [(() => a)() + ""]() { let a = "inside" } }`,
)
.get("body.1.body.body.0.key.left.callee.body")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
});
it("when path is in nested within another computed key", () => {
expect(
getPath(
`var a = "outside"; ({ get [ { get [a]() { let a = "inside"; return a; } }.outside ]() { let a = "middle"; return a; } })`,
)
.get("body.1.expression.properties.0.key.object.properties.0.key")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
expect(
getPath(
`var a = "outside"; class foo { static get [ class { static get [a]() { let a = "inside"; return a; } }.outside ]() { let a = "middle"; return a; } }`,
)
.get("body.1.body.body.0.key.object.body.body.0.key")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
});
});
it("should not have visibility on parameter bindings", () => {
expect(
getPath(`var a = "outside"; ({ [a](a = "inside") {} })`)
.get("body.1.expression.properties.0.key")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
expect(
getPath(`var a = "outside"; class foo { [a](a = "inside") {} }`)
.get("body.1.body.body.0.key")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
});
});
describe("decorator", () => {
const parserOptions = {
plugins: [["decorators", { decoratorsBeforeExport: true }]],
};
it("should not have visibility of declarations inside method body", () => {
expect(
getPath(
`var a = "outside"; class foo { @(() => () => a) m() { let a = "inside"; } }`,
parserOptions,
)
.get("body.1.body.body.0.decorators.0.expression.body.body")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
});
it("should not have visibility on parameter bindings", () => {
expect(
getPath(
`var a = "outside"; class foo { @(() => () => a) m(a = "inside") {} }`,
parserOptions,
)
.get("body.1.body.body.0.decorators.0.expression.body.body")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
});
});
it("switch discriminant scope", () => {
expect(
getPath(`let a = "outside"; switch (a) { default: let a = "inside" }`)
.get("body.1.discriminant")
.scope.getBinding("a").path.node.init.value,
).toBe("outside");
});
it("variable declaration", function () {
expect(getPath("var foo = null;").scope.getBinding("foo").path.type).toBe(
"VariableDeclarator",
);
expect(
getPath("var { foo } = null;").scope.getBinding("foo").path.type,
).toBe("VariableDeclarator");
expect(
getPath("var [ foo ] = null;").scope.getBinding("foo").path.type,
).toBe("VariableDeclarator");
expect(
getPath("var { bar: [ foo ] } = null;").scope.getBinding("foo").path
.type,
).toBe("VariableDeclarator");
});
it("declare var", function () {
expect(
getPath("declare var foo;", { plugins: ["flow"] }).scope.getBinding(
"foo",
).path.type,
).toBe("DeclareVariable");
});
it("declare function", function () {
expect(
getPath("declare function foo(): void;", {
plugins: ["flow"],
}).scope.getBinding("foo").path.type,
).toBe("DeclareFunction");
});
it("declare module", function () {
expect(
getPath("declare module foo {};", {
plugins: ["flow"],
}).scope.getBinding("foo").path.type,
).toBe("DeclareModule");
});
it("declare type alias", function () {
expect(
getPath("declare type foo = string;", {
plugins: ["flow"],
}).scope.getBinding("foo").path.type,
).toBe("DeclareTypeAlias");
});
it("declare opaque type", function () {
expect(
getPath("declare opaque type foo;", {
plugins: ["flow"],
}).scope.getBinding("foo").path.type,
).toBe("DeclareOpaqueType");
});
it("declare interface", function () {
expect(
getPath("declare interface Foo {};", {
plugins: ["flow"],
}).scope.getBinding("Foo").path.type,
).toBe("DeclareInterface");
});
it("type alias", function () {
expect(
getPath("type foo = string;", {
plugins: ["flow"],
}).scope.getBinding("foo").path.type,
).toBe("TypeAlias");
});
it("opaque type alias", function () {
expect(
getPath("opaque type foo = string;", {
plugins: ["flow"],
}).scope.getBinding("foo").path.type,
).toBe("OpaqueType");
});
it("interface", function () {
expect(
getPath("interface Foo {};", {
plugins: ["flow"],
}).scope.getBinding("Foo").path.type,
).toBe("InterfaceDeclaration");
});
it("import type", function () {
expect(
getPath("import type {Foo} from 'foo';", {
plugins: ["flow"],
}).scope.getBinding("Foo").path.type,
).toBe("ImportSpecifier");
});
it("variable constantness", function () {
expect(getPath("var a = 1;").scope.getBinding("a").constant).toBe(true);
expect(getPath("var a = 1; a = 2;").scope.getBinding("a").constant).toBe(
false,
);
expect(getPath("var a = 1, a = 2;").scope.getBinding("a").constant).toBe(
false,
);
expect(
getPath("var a = 1; var a = 2;").scope.getBinding("a").constant,
).toBe(false);
});
it("variable constantness in loops", () => {
let scopePath = null;
const isAConstant = code => {
let path = getPath(code);
if (scopePath) path = path.get(scopePath);
return path.scope.getBinding("a").constant;
};
expect(isAConstant("for (_ of ns) { var a = 1; }")).toBe(false);
expect(isAConstant("for (_ in ns) { var a = 1; }")).toBe(false);
expect(isAConstant("for (;;) { var a = 1; }")).toBe(false);
expect(isAConstant("while (1) { var a = 1; }")).toBe(false);
expect(isAConstant("do { var a = 1; } while (1)")).toBe(false);
expect(isAConstant("for (var a of ns) {}")).toBe(false);
expect(isAConstant("for (var a in ns) {}")).toBe(false);
expect(isAConstant("for (var a;;) {}")).toBe(true);
scopePath = "body.0.body.expression";
expect(isAConstant("for (_ of ns) () => { var a = 1; }")).toBe(true);
expect(isAConstant("for (_ in ns) () => { var a = 1; }")).toBe(true);
expect(isAConstant("for (;;) () => { var a = 1; }")).toBe(true);
expect(isAConstant("while (1) () => { var a = 1; }")).toBe(true);
expect(isAConstant("do () => { var a = 1; }; while (1)")).toBe(true);
scopePath = "body.0.body";
expect(isAConstant("for (_ of ns) { let a = 1; }")).toBe(true);
expect(isAConstant("for (_ in ns) { let a = 1; }")).toBe(true);
expect(isAConstant("for (;;) { let a = 1; }")).toBe(true);
expect(isAConstant("while (1) { let a = 1; }")).toBe(true);
expect(isAConstant("do { let a = 1; } while (1)")).toBe(true);
scopePath = "body.0";
expect(isAConstant("for (let a of ns) {}")).toBe(true);
expect(isAConstant("for (let a in ns) {}")).toBe(true);
expect(isAConstant("for (let a;;) {}")).toBe(true);
});
test("label", function () {
expect(getPath("foo: { }").scope.getBinding("foo")).toBeUndefined();
expect(getPath("foo: { }").scope.getLabel("foo").type).toBe(
"LabeledStatement",
);
expect(getPath("foo: { }").scope.getLabel("toString")).toBeUndefined();
expect(
getPath(
`
foo: { }
`,
).scope.generateUid("foo"),
).toBe("_foo");
});
test("generateUid collision check with labels", function () {
expect(
getPath(
`
_foo: { }
`,
).scope.generateUid("foo"),
).toBe("_foo2");
expect(
getPath(
`
_foo: { }
_foo1: { }
_foo2: { }
`,
).scope.generateUid("foo"),
).toBe("_foo3");
});
describe("reference paths", () => {
it("param referenced in function body", function () {
const path = getIdentifierPath("function square(n) { return n * n}");
const referencePaths = path.context.scope.bindings.n.referencePaths;
expect(referencePaths).toHaveLength(2);
expect(referencePaths[0].node.loc.start).toEqual({
line: 1,
column: 28,
index: 28,
});
expect(referencePaths[1].node.loc.start).toEqual({
line: 1,
column: 32,
index: 32,
});
});
it("id referenced in function body", () => {
const path = getIdentifierPath("(function n(m) { return n })");
const { referencePaths, identifier } = path.scope.getOwnBinding("n");
expect(identifier.start).toMatchInlineSnapshot(`10`);
expect(referencePaths).toHaveLength(1);
expect(referencePaths[0].node.start).toMatchInlineSnapshot(`24`);
});
it("id referenced in param initializer - function expression", () => {
const path = getIdentifierPath("(function n(m = n) {})");
const { referencePaths, identifier } = path.scope.getOwnBinding("n");
expect(identifier.start).toMatchInlineSnapshot(`10`);
expect(referencePaths).toHaveLength(1);
expect(referencePaths[0].node.start).toMatchInlineSnapshot(`16`);
});
it("id referenced in param initializer - function declaration", () => {
const path = getIdentifierPath("function n(m = n) {}");
const { referencePaths, identifier } = path.scope.getBinding("n");
expect(identifier.start).toMatchInlineSnapshot(`9`);
expect(referencePaths).toHaveLength(1);
expect(referencePaths[0].node.start).toMatchInlineSnapshot(`15`);
});
it("param referenced in function body with id collision", () => {
const path = getIdentifierPath("(function n(n) { return n })");
const { referencePaths, identifier } = path.scope.getOwnBinding("n");
expect(identifier.start).toMatchInlineSnapshot(`12`);
expect(referencePaths).toHaveLength(1);
expect(referencePaths[0].node.start).toMatchInlineSnapshot(`24`);
});
it("param referenced in param initializer with id collision", () => {
const path = getIdentifierPath("(function n(n, m = n) {})");
const { referencePaths, identifier } = path.scope.getOwnBinding("n");
expect(identifier.start).toMatchInlineSnapshot(`12`);
expect(referencePaths).toHaveLength(1);
expect(referencePaths[0].node.start).toMatchInlineSnapshot(`19`);
});
});
describe("after crawl", () => {
it("modified function identifier available in function scope", () => {
const path = getPath("(function f(f) {})")
.get("body")[0]
.get("expression");
path.get("id").replaceWith(t.identifier("g"));
path.scope.crawl();
const binding = path.scope.getBinding("g");
expect(binding.kind).toBe("local");
});
it("modified function param available in function scope", () => {
const path = getPath("(function f(f) {})")
.get("body")[0]
.get("expression");
path.get("params")[0].replaceWith(t.identifier("g"));
path.scope.crawl();
const binding = path.scope.getBinding("g");
expect(binding.kind).toBe("param");
});
it("modified class identifier available in class expression scope", () => {
const path = getPath("(class c {})").get("body")[0].get("expression");
path.get("id").replaceWith(t.identifier("g"));
path.scope.crawl();
const binding = path.scope.getBinding("g");
expect(binding.kind).toBe("local");
});
it("modified class identifier available in class declaration scope", () => {
const path = getPath("class c {}").get("body")[0];
path.get("id").replaceWith(t.identifier("g"));
path.scope.crawl();
const binding = path.scope.getBinding("g");
expect(binding.kind).toBe("let");
});
});
it("class identifier available in class scope after crawl", function () {
const path = getPath("class a { build() { return new a(); } }");
path.scope.crawl();
let referencePaths = path.scope.bindings.a.referencePaths;
expect(referencePaths).toHaveLength(1);
referencePaths = path.get("body[0]").scope.bindings.a.referencePaths;
expect(referencePaths).toHaveLength(1);
expect(path.scope.bindings.a).toBe(path.get("body[0]").scope.bindings.a);
});
it("references after re-crawling", function () {
const path = getPath("function Foo() { var _jsx; }");
path.scope.crawl();
path.scope.crawl();
expect(path.scope.references._jsx).toBe(true);
});
test("generateUid collision check after re-crawling", function () {
const path = getPath("function Foo() { var _jsx; }");
path.scope.crawl();
path.scope.crawl();
expect(path.scope.generateUid("jsx")).toBe("_jsx2");
});
test("generateUid collision check after re-crawling (function expression local id)", function () {
const path = getPath("var fn = function _name(){}");
path.scope.crawl();
path.scope.crawl();
expect(path.scope.generateUid("name")).toBe("_name2");
});
test("generateUid collision check after re-crawling (function params)", function () {
const path = getPath("[].map(_unicorn => [_unicorn])");
path.scope.crawl();
path.scope.crawl();
expect(path.scope.generateUid("unicorn")).toBe("_unicorn2");
});
test("generateUid collision check after re-crawling (catch clause)", function () {
const path = getPath("try {} catch (_err) {}");
path.scope.crawl();
path.scope.crawl();
expect(path.scope.generateUid("err")).toBe("_err2");
});
test("generateUid collision check after re-crawling (class expression local id)", function () {
const path = getPath("var C = class _Cls{}");
path.scope.crawl();
path.scope.crawl();
expect(path.scope.generateUid("Cls")).toBe("_Cls2");
});
it("re-exports are not references", () => {
const path = getPath("export { x } from 'y'", {
sourceType: "module",
});
expect(path.scope.hasGlobal("x")).toBe(false);
});
});
describe("duplicate bindings", () => {
/*
* These tests do not use the parser as the parser has
* its own scope tracking and we want to test the scope tracking
* of traverse here and see if it handles duplicate bindings correctly
*/
describe("catch", () => {
// try {} catch (e) { let e; }
const createTryCatch = function (kind) {
return t.tryStatement(
t.blockStatement([]),
t.catchClause(
t.identifier("e"),
t.blockStatement([
t.variableDeclaration(kind, [
t.variableDeclarator(t.identifier("e"), t.stringLiteral("1")),
]),
]),
),
);
};
it("let", () => {
const ast = createTryCatch("let");
expect(() => getPath(ast)).toThrowErrorMatchingSnapshot();
});
it("const", () => {
const ast = createTryCatch("const");
expect(() => getPath(ast)).toThrowErrorMatchingSnapshot();
});
it("using", () => {
const ast = createTryCatch("using");
expect(() => getPath(ast)).toThrowErrorMatchingSnapshot();
});
it("var", () => {
const ast = createTryCatch("var");
expect(() => getPath(ast)).not.toThrow();
});
});
["let", "const"].forEach(name => {
it(`${name} and function in sub scope`, () => {
const ast = [
t.variableDeclaration(name, [
t.variableDeclarator(t.identifier("foo")),
]),
t.blockStatement([
t.functionDeclaration(
t.identifier("foo"),
[],
t.blockStatement([]),
),
]),
];
expect(() => getPath(ast)).not.toThrow();
});
});
describe("duplicate declaration", () => {
it("should not throw error on duplicate class and function declaration", () => {
const ast = [
t.classDeclaration(t.identifier("A"), null, t.classBody([]), []),
t.functionDeclaration(t.identifier("A"), [], t.blockStatement([])),
];
ast[0].declare = true;
expect(() => getPath(ast)).not.toThrowError();
});
});
describe("global", () => {
// node1, node2, success
// every line will run 2 tests `node1;node2;` and `node2;node1;`
// unless node1 === node2
const cases = [
["const", "let", false],
["const", "const", false],
["const", "function", false],
["const", "class", false],
["const", "var", false],
["let", "let", false],
["let", "class", false],
["let", "function", false],
["let", "var", false],
["var", "class", false],
["var", "function", true],
["var", "var", true],
["class", "function", false],
["class", "class", false],
["function", "function", true],
];
const createNode = function (kind) {
switch (kind) {
case "let":
case "const":
case "var":
return t.variableDeclaration(kind, [
t.variableDeclarator(t.identifier("foo")),
]);
case "class":
return t.classDeclaration(
t.identifier("foo"),
null,
t.classBody([]),
);
case "function":
return t.functionDeclaration(
t.identifier("foo"),
[],
t.blockStatement([]),
);
}
};
const createAST = function (kind1, kind2) {
return [createNode(kind1), createNode(kind2)];
};
for (const [kind1, kind2, success] of cases) {
if (success) {
it(`${kind1}/${kind2} should succeed`, () => {
const ast = createAST(kind1, kind2);
expect(() => getPath(ast)).not.toThrow();
});
} else {
it(`${kind1}/${kind2} should fail`, () => {
const ast = createAST(kind1, kind2);
expect(() => getPath(ast)).toThrowErrorMatchingSnapshot();
});
}
if (kind1 !== kind2) {
// todo: remove the if allowed
if (kind1 === "const" && (kind2 === "function" || kind2 === "var")) {
continue;
}
if (success) {
it(`${kind2}/${kind1} should succeed`, () => {
const ast = createAST(kind2, kind1);
expect(() => getPath(ast)).not.toThrow();
});
} else {
it(`${kind2}/${kind1} should fail`, () => {
const ast = createAST(kind2, kind1);
expect(() => getPath(ast)).toThrowErrorMatchingSnapshot();
});
}
}
}
});
});
describe("own bindings", () => {
// Var declarations should be declared in the nearest FunctionParent ancestry
describe("var declarations should be registered", () => {
it("in program", () => {
const program = getPath("var foo;");
expect(program.scope.hasOwnBinding("foo")).toBe(true);
});
it("in function declaration", () => {
const functionDeclaration = getPath("function f() { var foo; }").get(
"body.0",
);
expect(functionDeclaration.scope.hasOwnBinding("foo")).toBe(true);
});
it("in function expression", () => {
const functionExpression = getPath("(function () { var foo; })").get(
"body.0.expression",
);
expect(functionExpression.scope.hasOwnBinding("foo")).toBe(true);
});
it("in arrow expression", () => {
const arrowExpression =
getPath("() => { var foo; }").get("body.0.expression");
expect(arrowExpression.scope.hasOwnBinding("foo")).toBe(true);
});
it("in object method", () => {
const objectMethod = getPath("({ method() { var foo; } })").get(
"body.0.expression.properties.0",
);
expect(objectMethod.scope.hasOwnBinding("foo")).toBe(true);
});
it("in class method", () => {
const classMethod = getPath("(class { method() { var foo; } })").get(
"body.0.expression.body.body.0",
);
expect(classMethod.scope.hasOwnBinding("foo")).toBe(true);
});
it("in class private method", () => {
const classMethod = getPath("(class { #method() { var foo; } })").get(
"body.0.expression.body.body.0",
);
expect(classMethod.scope.hasOwnBinding("foo")).toBe(true);
});
it("in static block", () => {
const staticBlock = getPath("(class { static { var foo; } })", {
plugins: ["classStaticBlock"],
}).get("body.0.expression.body.body.0");
expect(staticBlock.scope.hasOwnBinding("foo")).toBe(true);
});
});
describe("var declarations should not be registered", () => {
it("in block statement", () => {
const blockStatement = getPath("{ var foo; }").get("body.0");
expect(blockStatement.scope.hasOwnBinding("foo")).toBe(false);
});
it("in catch clause", () => {
const catchClause = getPath("try {} catch { var foo; }").get(
"body.0.handler",
);
expect(catchClause.scope.hasOwnBinding("foo")).toBe(false);
});
it("in for-init statement", () => {
const forStatement = getPath("for (var foo;;);").get("body.0");
expect(forStatement.scope.hasOwnBinding("foo")).toBe(false);
});
it("in for-in statement", () => {
const forStatement = getPath("for (var foo in x);").get("body.0");
expect(forStatement.scope.hasOwnBinding("foo")).toBe(false);
});
it("in for-of statement", () => {
const forStatement = getPath("for (var foo of x);").get("body.0");
expect(forStatement.scope.hasOwnBinding("foo")).toBe(false);
});
it("in switch statement", () => {
const switchStatement = getPath("switch (0) { case 0: var foo; }").get(
"body.0",
);
expect(switchStatement.scope.hasOwnBinding("foo")).toBe(false);
});
it("in while statement", () => {
const whileStatement = getPath("while (0) \n var foo;").get("body.0");
expect(whileStatement.scope.hasOwnBinding("foo")).toBe(false);
});
it("in do-while statement", () => {
const doWhileStatement = getPath("do \n var foo \n while(0);").get(
"body.0",
);
expect(doWhileStatement.scope.hasOwnBinding("foo")).toBe(false);
});
});
// Lexical declarations should be registered in the nearest BlockParent ancestry
describe("let declarations should be registered", () => {
it("in program", () => {
const program = getPath("let foo;");
expect(program.scope.hasOwnBinding("foo")).toBe(true);
});
it("in function declaration", () => {
const functionDeclaration = getPath("function f() { let foo; }").get(
"body.0",
);
expect(functionDeclaration.scope.hasOwnBinding("foo")).toBe(true);
});
it("in function expression", () => {
const functionExpression = getPath("(function () { let foo; })").get(
"body.0.expression",
);
expect(functionExpression.scope.hasOwnBinding("foo")).toBe(true);
});
it("in arrow expression", () => {
const arrowExpression =
getPath("() => { let foo; }").get("body.0.expression");
expect(arrowExpression.scope.hasOwnBinding("foo")).toBe(true);
});
it("in object method", () => {
const objectMethod = getPath("({ method() { let foo; } })").get(
"body.0.expression.properties.0",
);
expect(objectMethod.scope.hasOwnBinding("foo")).toBe(true);
});
it("in class method", () => {
const classMethod = getPath("(class { method() { let foo; } })").get(
"body.0.expression.body.body.0",
);
expect(classMethod.scope.hasOwnBinding("foo")).toBe(true);
});
it("in class private method", () => {
const classMethod = getPath("(class { #method() { let foo; } })").get(
"body.0.expression.body.body.0",
);
expect(classMethod.scope.hasOwnBinding("foo")).toBe(true);
});
it("in static block", () => {
const staticBlock = getPath("(class { static { let foo; } })", {
plugins: ["classStaticBlock"],
}).get("body.0.expression.body.body.0");
expect(staticBlock.scope.hasOwnBinding("foo")).toBe(true);
});
it("in block statement", () => {
const blockStatement = getPath("{ let foo; }").get("body.0");
expect(blockStatement.scope.hasOwnBinding("foo")).toBe(true);
});
it("in catch clause", () => {
const catchClause = getPath("try {} catch { let foo; }").get(
"body.0.handler",
);
expect(catchClause.scope.hasOwnBinding("foo")).toBe(true);
});
it("in for-init statement", () => {
const forStatement = getPath("for (let foo;;);").get("body.0");
expect(forStatement.scope.hasOwnBinding("foo")).toBe(true);
});
it("in for-in statement", () => {
const forStatement = getPath("for (let foo in x);").get("body.0");
expect(forStatement.scope.hasOwnBinding("foo")).toBe(true);
});
it("in for-of statement", () => {
const forStatement = getPath("for (let foo of x);").get("body.0");
expect(forStatement.scope.hasOwnBinding("foo")).toBe(true);
});
it("in switch statement", () => {
const switchStatement = getPath("switch (0) { case 0: let foo; }").get(
"body.0",
);
expect(switchStatement.scope.hasOwnBinding("foo")).toBe(true);
});
});
});
describe(".push", () => {
it("registers the new binding in the correct scope", () => {
const program = getPath("class A {}");
const classDeclaration = program.get("body.0");
classDeclaration.scope.push({ id: t.identifier("class") });
expect(program.toString()).toMatchInlineSnapshot(`
"var class;
class A {}"
`);
expect(program.scope.hasOwnBinding("class")).toBe(true);
});
it("registers the new binding outside function when the path is a param initializer", () => {
const program = getPath("(a = f()) => {}");
const assignmentPattern = program.get("body.0.expression.params.0");
assignmentPattern.scope.push({ id: t.identifier("ref") });
expect(program.toString()).toMatchInlineSnapshot(`
"var ref;
(a = f()) => {};"
`);
expect(program.scope.hasOwnBinding("ref")).toBe(true);
});
it("registers the new binding outside class method when the path is a param initializer", () => {
const program = getPath("class C { m(a = f()) {} }");
const assignmentPattern = program.get("body.0.body.body.0.params.0");
assignmentPattern.scope.push({ id: t.identifier("ref") });
expect(program.toString()).toMatchInlineSnapshot(`
"var ref;
class C {
m(a = f()) {}
}"