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// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-id-iter-val-array-prototype.case
// - src/dstr-binding/default/for-var.template
/*---
description: Array destructuring uses overriden Array.prototype[Symbol.iterator] (for statement)
esid: sec-for-statement-runtime-semantics-labelledevaluation
features: [Symbol.iterator, generators, destructuring-binding]
flags: [generated]
info: |
IterationStatement :
for ( var VariableDeclarationList ; Expressionopt ; Expressionopt ) Statement
1. Let varDcl be the result of evaluating VariableDeclarationList.
[...]
13.3.2.4 Runtime Semantics: Evaluation
VariableDeclarationList : VariableDeclarationList , VariableDeclaration
1. Let next be the result of evaluating VariableDeclarationList.
2. ReturnIfAbrupt(next).
3. Return the result of evaluating VariableDeclaration.
VariableDeclaration : BindingPattern Initializer
1. Let rhs be the result of evaluating Initializer.
2. Let rval be GetValue(rhs).
3. ReturnIfAbrupt(rval).
4. Return the result of performing BindingInitialization for BindingPattern
passing rval and undefined as arguments.
Runtime Semantics: IteratorBindingInitialization
SingleNameBinding : BindingIdentifier Initializer_opt
1. Let bindingId be StringValue of BindingIdentifier.
2. Let lhs be ? ResolveBinding(bindingId, environment).
3. If iteratorRecord.[[Done]] is false, then
a. Let next be IteratorStep(iteratorRecord).
b. If next is an abrupt completion, set iteratorRecord.[[Done]] to true.
c. ReturnIfAbrupt(next).
d. If next is false, set iteratorRecord.[[Done]] to true.
e. Else,
i. Let v be IteratorValue(next).
ii. If v is an abrupt completion, set iteratorRecord.[[Done]] to true.
iii. ReturnIfAbrupt(v).
[...]
7. Return InitializeReferencedBinding(lhs, v).
---*/
Array.prototype[Symbol.iterator] = function* () {
if (this.length > 0) {
yield this[0];
}
if (this.length > 1) {
yield this[1];
}
if (this.length > 2) {
yield 42;
}
};
var iterCount = 0;
for (var [x, y, z] = [1, 2, 3]; iterCount < 1; ) {
assert.sameValue(x, 1);
assert.sameValue(y, 2);
assert.sameValue(z, 42);
iterCount += 1;
}
assert.sameValue(iterCount, 1, 'Iteration occurred as expected');
reportCompare(0, 0);
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