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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/dstr-assignment-for-await/array-elem-trlg-iter-elision-iter-nrml-close-skip.case
// - src/dstr-assignment-for-await/async-generator/async-gen-decl.template
/*---
description: IteratorClose not invoked when elision exhausts the iterator (for-await-of statement in an async generator declaration)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [Symbol.iterator, destructuring-binding, async-iteration]
flags: [generated, async]
info: |
IterationStatement :
for await ( LeftHandSideExpression of AssignmentExpression ) Statement
1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« »,
AssignmentExpression, iterate).
2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement,
keyResult, assignment, labelSet).
13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
[...]
5. If destructuring is true and if lhsKind is assignment, then
a. Assert: lhs is a LeftHandSideExpression.
b. Let assignmentPattern be the parse of the source text corresponding to
lhs using AssignmentPattern as the goal symbol.
[...]
ArrayAssignmentPattern :
[ AssignmentElementList , Elisionopt AssignmentRestElementopt ]
[...]
5. If Elision is present, then
a. Let status be the result of performing
IteratorDestructuringAssignmentEvaluation of Elision with
iteratorRecord as the argument.
b. If status is an abrupt completion, then
[...]
7. If iteratorRecord.[[done]] is false, return IteratorClose(iterator,
status).
9. Return Completion(status).
---*/
let nextCount = 0;
let returnCount = 0;
let x;
let iterator = {
next() {
nextCount += 1;
return { done: nextCount > 1 };
},
return() {
returnCount += 1;
}
};
let iterable = {
[Symbol.iterator]() {
return iterator;
}
};
let iterCount = 0;
async function * fn() {
for await ([ x , , ] of [iterable]) {
assert.sameValue(nextCount, 2);
assert.sameValue(returnCount, 0);
iterCount += 1;
}
}
let iter = fn();
iter.next()
.then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE)
.then($DONE, $DONE);
|
