diff --git a/src/compiler/transformers/es2015.ts b/src/compiler/transformers/es2015.ts
index f7c20e74d6717..991cab51c252a 100644
--- a/src/compiler/transformers/es2015.ts
+++ b/src/compiler/transformers/es2015.ts
@@ -145,7 +145,15 @@ namespace ts {
loopOutParameters: LoopOutParameter[];
}
- type LoopConverter = (node: IterationStatement, outermostLabeledStatement: LabeledStatement | undefined, convertedLoopBodyStatements: Statement[] | undefined, ancestorFacts: HierarchyFacts) => Statement;
+ type DirectLoopConverter = (node: IterationStatement, outermostLabeledStatement: LabeledStatement | undefined, convertedLoopBodyStatements: Statement[] | undefined, ancestorFacts: HierarchyFacts) => Statement;
+ type TransformedLoopConverter = (node: IterationStatement, outermostLabeledStatement: LabeledStatement | undefined, convertedLoopBodyStatements: Statement[] | undefined, ancestorFacts: HierarchyFacts, initializerFunction: IterationStatementPartFunction<VariableDeclarationList> | undefined, bodyFunction: IterationStatementPartFunction<Statement[]>) => Statement;
+
+ interface IterationStatementPartFunction<T> {
+ functionName: Identifier;
+ functionDeclaration: Statement;
+ containsYield: boolean;
+ part: T;
+ }
// Facts we track as we traverse the tree
const enum HierarchyFacts {
@@ -2284,9 +2292,9 @@ namespace ts {
}
}
- function visitIterationStatementWithFacts(excludeFacts: HierarchyFacts, includeFacts: HierarchyFacts, node: IterationStatement, outermostLabeledStatement: LabeledStatement | undefined, convert?: LoopConverter) {
+ function visitIterationStatementWithFacts(excludeFacts: HierarchyFacts, includeFacts: HierarchyFacts, node: IterationStatement, outermostLabeledStatement: LabeledStatement | undefined, convertDirectly?: DirectLoopConverter, convertWithTransform?: TransformedLoopConverter) {
const ancestorFacts = enterSubtree(excludeFacts, includeFacts);
- const updated = convertIterationStatementBodyIfNecessary(node, outermostLabeledStatement, ancestorFacts, convert);
+ const updated = convertIterationStatementBodyIfNecessary(node, outermostLabeledStatement, ancestorFacts, convertDirectly, convertWithTransform);
exitSubtree(ancestorFacts, HierarchyFacts.None, HierarchyFacts.None);
return updated;
}
@@ -2322,19 +2330,23 @@ namespace ts {
HierarchyFacts.ForInOrForOfStatementExcludes,
HierarchyFacts.ForInOrForOfStatementIncludes,
node,
- outermostLabeledStatement);
+ outermostLabeledStatement,
+ convertForInStatementForLoopDirectly,
+ convertForInStatementForLoopTransformed);
}
function visitForOfStatement(node: ForOfStatement, outermostLabeledStatement: LabeledStatement | undefined): VisitResult<Statement> {
+ const convert = compilerOptions.downlevelIteration ? convertForOfStatementForIterable : convertForOfStatementForArray;
return visitIterationStatementWithFacts(
HierarchyFacts.ForInOrForOfStatementExcludes,
HierarchyFacts.ForInOrForOfStatementIncludes,
node,
outermostLabeledStatement,
- compilerOptions.downlevelIteration ? convertForOfStatementForIterable : convertForOfStatementForArray);
+ convert,
+ convert);
}
- function convertForOfStatementHead(node: ForOfStatement, boundValue: Expression, convertedLoopBodyStatements: Statement[]) {
+ function convertForStatementHead(node: ForInStatement | ForOfStatement, boundValue: Expression, convertedLoopBodyStatements: Statement[]) {
const statements: Statement[] = [];
const initializer = node.initializer;
if (isVariableDeclarationList(initializer)) {
@@ -2433,6 +2445,77 @@ namespace ts {
);
}
+ function convertForInStatementForLoopDirectly(node: ForInStatement, outermostLabeledStatement: LabeledStatement, convertedLoopBodyStatements: Statement[]): Statement {
+ // The following ES2015 code:
+ //
+ // for (var [a, b] in expr) { }
+ //
+ // should be emitted as
+ //
+ // for (var _a in expr) {
+ // var a = _a[0], b = _a[1];
+ // }
+ //
+ // where _a is a temp emitted to capture the LHS binding.
+ const initializerBinding = getForInInitializerBindingDeclaration(node);
+ if (initializerBinding) {
+ return convertForInStatementWithInitializerBinding(node, convertedLoopBodyStatements, initializerBinding);
+ }
+
+ return factory.restoreEnclosingLabel(visitEachChild(node, visitor, context), outermostLabeledStatement, convertedLoopState && resetLabel);
+ }
+
+ function convertForInStatementForLoopTransformed(node: ForInStatement, outermostLabeledStatement: LabeledStatement, convertedLoopBodyStatements: Statement[], _ancestorFacts: HierarchyFacts, initializerFunction: IterationStatementPartFunction<VariableDeclarationList> | undefined, bodyFunction: IterationStatementPartFunction<Statement[]>): Statement {
+ // The following ES2015 code:
+ //
+ // for (let [a, b] in expr) { ... }
+ //
+ // should be emitted as
+ //
+ // var _loop_1 = function (_a) {
+ // var a = _a[0], b = _a[1];
+ // ...
+ // }
+ // for (var _a in expr) {
+ // _loop_1(a);
+ // }
+ //
+ // where _a is a temp emitted to capture the LHS binding.
+ const initializerBinding = getForInInitializerBindingDeclaration(node);
+ if (initializerBinding) {
+ return convertForInStatementWithInitializerBinding(node, convertedLoopBodyStatements, initializerBinding);
+ }
+
+ const clone = convertIterationStatementCore(node, initializerFunction, factory.createBlock(bodyFunction.part, /*multiLine*/ true));
+ return factory.restoreEnclosingLabel(clone, outermostLabeledStatement, convertedLoopState && resetLabel);
+ }
+
+ function convertForInStatementWithInitializerBinding(node: ForInStatement, convertedLoopBodyStatements: Statement[], _initializerBinding: VariableDeclaration) {
+ const tempInitializer = factory.createTempVariable(/*recordTempVariable*/ undefined);
+
+ return factory.createForInStatement(
+ factory.createVariableDeclarationList([factory.createVariableDeclaration(tempInitializer)]),
+ node.expression,
+ convertForStatementHead(
+ node,
+ tempInitializer,
+ convertedLoopBodyStatements,
+ )
+ );
+ }
+
+ function getForInInitializerBindingDeclaration(node: ForInStatement) {
+ if (!isVariableDeclarationList(node.initializer) || node.initializer.declarations.length === 0) {
+ return undefined;
+ }
+
+ const declaration = node.initializer.declarations[0];
+
+ return isArrayBindingPattern(declaration.name) || isObjectBindingPattern(declaration.name)
+ ? declaration
+ : undefined;
+ }
+
function convertForOfStatementForArray(node: ForOfStatement, outermostLabeledStatement: LabeledStatement, convertedLoopBodyStatements: Statement[]): Statement {
// The following ES6 code:
//
@@ -2488,7 +2571,7 @@ namespace ts {
node.expression
),
/*incrementor*/ setTextRange(factory.createPostfixIncrement(counter), node.expression),
- /*statement*/ convertForOfStatementHead(
+ /*statement*/ convertForStatementHead(
node,
factory.createElementAccessExpression(rhsReference, counter),
convertedLoopBodyStatements
@@ -2536,7 +2619,7 @@ namespace ts {
),
/*condition*/ factory.createLogicalNot(factory.createPropertyAccessExpression(result, "done")),
/*incrementor*/ factory.createAssignment(result, next),
- /*statement*/ convertForOfStatementHead(
+ /*statement*/ convertForStatementHead(
node,
factory.createPropertyAccessExpression(result, "value"),
convertedLoopBodyStatements
@@ -2731,7 +2814,7 @@ namespace ts {
}
}
- function convertIterationStatementBodyIfNecessary(node: IterationStatement, outermostLabeledStatement: LabeledStatement | undefined, ancestorFacts: HierarchyFacts, convert?: LoopConverter): VisitResult<Statement> {
+ function convertIterationStatementBodyIfNecessary(node: IterationStatement, outermostLabeledStatement: LabeledStatement | undefined, ancestorFacts: HierarchyFacts, convertDirectly?: DirectLoopConverter, convertWithTransform?: TransformedLoopConverter): VisitResult<Statement> {
if (!shouldConvertIterationStatement(node)) {
let saveAllowedNonLabeledJumps: Jump | undefined;
if (convertedLoopState) {
@@ -2741,8 +2824,8 @@ namespace ts {
convertedLoopState.allowedNonLabeledJumps = Jump.Break | Jump.Continue;
}
- const result = convert
- ? convert(node, outermostLabeledStatement, /*convertedLoopBodyStatements*/ undefined, ancestorFacts)
+ const result = convertDirectly
+ ? convertDirectly(node, outermostLabeledStatement, /*convertedLoopBodyStatements*/ undefined, ancestorFacts)
: factory.restoreEnclosingLabel(
isForStatement(node) ? visitEachChildOfForStatement(node) : visitEachChild(node, visitor, context),
outermostLabeledStatement,
@@ -2776,8 +2859,8 @@ namespace ts {
let loop: Statement;
if (bodyFunction) {
- if (convert) {
- loop = convert(node, outermostLabeledStatement, bodyFunction.part, ancestorFacts);
+ if (convertWithTransform) {
+ loop = convertWithTransform(node, outermostLabeledStatement, bodyFunction.part, ancestorFacts, initializerFunction, bodyFunction);
}
else {
const clone = convertIterationStatementCore(node, initializerFunction, factory.createBlock(bodyFunction.part, /*multiLine*/ true));
@@ -2981,13 +3064,6 @@ namespace ts {
}
}
- interface IterationStatementPartFunction<T> {
- functionName: Identifier;
- functionDeclaration: Statement;
- containsYield: boolean;
- part: T;
- }
-
function createOutVariable(p: LoopOutParameter) {
return factory.createVariableDeclaration(p.originalName, /*exclamationToken*/ undefined, /*type*/ undefined, p.outParamName);
}
diff --git a/tests/baselines/reference/for-inStatementsDestructuring.errors.txt b/tests/baselines/reference/for-inStatementsDestructuring.errors.txt
index e54f2c93272a3..f324d60738137 100644
--- a/tests/baselines/reference/for-inStatementsDestructuring.errors.txt
+++ b/tests/baselines/reference/for-inStatementsDestructuring.errors.txt
@@ -1,10 +1,44 @@
tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(1,10): error TS2461: Type 'string' is not an array type.
tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(1,10): error TS2491: The left-hand side of a 'for...in' statement cannot be a destructuring pattern.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(2,10): error TS2491: The left-hand side of a 'for...in' statement cannot be a destructuring pattern.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(2,12): error TS2339: Property 'a' does not exist on type 'String'.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(2,15): error TS2339: Property 'b' does not exist on type 'String'.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(4,10): error TS2461: Type 'string' is not an array type.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(4,10): error TS2491: The left-hand side of a 'for...in' statement cannot be a destructuring pattern.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(8,10): error TS2491: The left-hand side of a 'for...in' statement cannot be a destructuring pattern.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(8,12): error TS2339: Property 'a' does not exist on type 'String'.
+tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts(8,15): error TS2339: Property 'b' does not exist on type 'String'.
-==== tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts (2 errors) ====
+==== tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts (10 errors) ====
for (var [a, b] in []) {}
~~~~~~
!!! error TS2461: Type 'string' is not an array type.
~~~~~~
-!!! error TS2491: The left-hand side of a 'for...in' statement cannot be a destructuring pattern.
\ No newline at end of file
+!!! error TS2491: The left-hand side of a 'for...in' statement cannot be a destructuring pattern.
+ for (var { a, b } in []) {}
+ ~~~~~~~~
+!!! error TS2491: The left-hand side of a 'for...in' statement cannot be a destructuring pattern.
+ ~
+!!! error TS2339: Property 'a' does not exist on type 'String'.
+ ~
+!!! error TS2339: Property 'b' does not exist on type 'String'.
+
+ for (let [a, b] in []) {
+ ~~~~~~
+!!! error TS2461: Type 'string' is not an array type.
+ ~~~~~~
+!!! error TS2491: The left-hand side of a 'for...in' statement cannot be a destructuring pattern.
+ (() => a + b);
+ }
+
+ for (let { a, b } in []) {
+ ~~~~~~~~
+!!! error TS2491: The left-hand side of a 'for...in' statement cannot be a destructuring pattern.
+ ~
+!!! error TS2339: Property 'a' does not exist on type 'String'.
+ ~
+!!! error TS2339: Property 'b' does not exist on type 'String'.
+ (() => a + b);
+ }
+
\ No newline at end of file
diff --git a/tests/baselines/reference/for-inStatementsDestructuring.js b/tests/baselines/reference/for-inStatementsDestructuring.js
index e5e00d5b3ab56..f490e787b22ec 100644
--- a/tests/baselines/reference/for-inStatementsDestructuring.js
+++ b/tests/baselines/reference/for-inStatementsDestructuring.js
@@ -1,5 +1,34 @@
//// [for-inStatementsDestructuring.ts]
-for (var [a, b] in []) {}
+for (var [a, b] in []) {}
+for (var { a, b } in []) {}
+
+for (let [a, b] in []) {
+ (() => a + b);
+}
+
+for (let { a, b } in []) {
+ (() => a + b);
+}
+
//// [for-inStatementsDestructuring.js]
-for (var _a = void 0, a = _a[0], b = _a[1] in []) { }
+for (var _a in []) {
+ var a = _a[0], b = _a[1];
+}
+for (var _b in []) {
+ var a = _b.a, b = _b.b;
+}
+var _loop_1 = function (a_1, b_1) {
+ (function () { return a_1 + b_1; });
+};
+for (var _c in []) {
+ var a_1 = _c[0], b_1 = _c[1];
+ _loop_1(a_1, b_1);
+}
+var _loop_2 = function (a_2, b_2) {
+ (function () { return a_2 + b_2; });
+};
+for (var _d in []) {
+ var a_2 = _d.a, b_2 = _d.b;
+ _loop_2(a_2, b_2);
+}
diff --git a/tests/baselines/reference/for-inStatementsDestructuring.symbols b/tests/baselines/reference/for-inStatementsDestructuring.symbols
index fff70d63bd353..04c3a07077349 100644
--- a/tests/baselines/reference/for-inStatementsDestructuring.symbols
+++ b/tests/baselines/reference/for-inStatementsDestructuring.symbols
@@ -1,5 +1,27 @@
=== tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts ===
for (var [a, b] in []) {}
->a : Symbol(a, Decl(for-inStatementsDestructuring.ts, 0, 10))
->b : Symbol(b, Decl(for-inStatementsDestructuring.ts, 0, 12))
+>a : Symbol(a, Decl(for-inStatementsDestructuring.ts, 0, 10), Decl(for-inStatementsDestructuring.ts, 1, 10))
+>b : Symbol(b, Decl(for-inStatementsDestructuring.ts, 0, 12), Decl(for-inStatementsDestructuring.ts, 1, 13))
+
+for (var { a, b } in []) {}
+>a : Symbol(a, Decl(for-inStatementsDestructuring.ts, 0, 10), Decl(for-inStatementsDestructuring.ts, 1, 10))
+>b : Symbol(b, Decl(for-inStatementsDestructuring.ts, 0, 12), Decl(for-inStatementsDestructuring.ts, 1, 13))
+
+for (let [a, b] in []) {
+>a : Symbol(a, Decl(for-inStatementsDestructuring.ts, 3, 10))
+>b : Symbol(b, Decl(for-inStatementsDestructuring.ts, 3, 12))
+
+ (() => a + b);
+>a : Symbol(a, Decl(for-inStatementsDestructuring.ts, 3, 10))
+>b : Symbol(b, Decl(for-inStatementsDestructuring.ts, 3, 12))
+}
+
+for (let { a, b } in []) {
+>a : Symbol(a, Decl(for-inStatementsDestructuring.ts, 7, 10))
+>b : Symbol(b, Decl(for-inStatementsDestructuring.ts, 7, 13))
+
+ (() => a + b);
+>a : Symbol(a, Decl(for-inStatementsDestructuring.ts, 7, 10))
+>b : Symbol(b, Decl(for-inStatementsDestructuring.ts, 7, 13))
+}
diff --git a/tests/baselines/reference/for-inStatementsDestructuring.types b/tests/baselines/reference/for-inStatementsDestructuring.types
index 547e54a574195..ce8518fcb60fd 100644
--- a/tests/baselines/reference/for-inStatementsDestructuring.types
+++ b/tests/baselines/reference/for-inStatementsDestructuring.types
@@ -4,3 +4,34 @@ for (var [a, b] in []) {}
>b : any
>[] : undefined[]
+for (var { a, b } in []) {}
+>a : any
+>b : any
+>[] : undefined[]
+
+for (let [a, b] in []) {
+>a : any
+>b : any
+>[] : undefined[]
+
+ (() => a + b);
+>(() => a + b) : () => any
+>() => a + b : () => any
+>a + b : any
+>a : any
+>b : any
+}
+
+for (let { a, b } in []) {
+>a : any
+>b : any
+>[] : undefined[]
+
+ (() => a + b);
+>(() => a + b) : () => any
+>() => a + b : () => any
+>a + b : any
+>a : any
+>b : any
+}
+
diff --git a/tests/baselines/reference/for-inStatementsDestructuring2.js b/tests/baselines/reference/for-inStatementsDestructuring2.js
index 41a6d30919f50..5c384b1c9dfa9 100644
--- a/tests/baselines/reference/for-inStatementsDestructuring2.js
+++ b/tests/baselines/reference/for-inStatementsDestructuring2.js
@@ -2,4 +2,6 @@
for (var {a, b} in []) {}
//// [for-inStatementsDestructuring2.js]
-for (var _a = void 0, a = _a.a, b = _a.b in []) { }
+for (var _a in []) {
+ var a = _a.a, b = _a.b;
+}
diff --git a/tests/baselines/reference/jsDeclarationsSubclassWithExplicitNoArgumentConstructor.js b/tests/baselines/reference/jsDeclarationsSubclassWithExplicitNoArgumentConstructor.js
index 42cafa5e355a0..8abe7764586b0 100644
--- a/tests/baselines/reference/jsDeclarationsSubclassWithExplicitNoArgumentConstructor.js
+++ b/tests/baselines/reference/jsDeclarationsSubclassWithExplicitNoArgumentConstructor.js
@@ -23,6 +23,8 @@ var __extends = (this && this.__extends) || (function () {
return extendStatics(d, b);
};
return function (d, b) {
+ if (typeof b !== "function" && b !== null)
+ throw new TypeError("Class extends value " + String(b) + " is not a constructor or null");
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
diff --git a/tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts b/tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts
index 94868ef3bd62e..d73963a82b51e 100644
--- a/tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts
+++ b/tests/cases/conformance/statements/for-inStatements/for-inStatementsDestructuring.ts
@@ -1 +1,10 @@
-for (var [a, b] in []) {}
\ No newline at end of file
+for (var [a, b] in []) {}
+for (var { a, b } in []) {}
+
+for (let [a, b] in []) {
+ (() => a + b);
+}
+
+for (let { a, b } in []) {
+ (() => a + b);
+}