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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/dstr-assignment-for-await/array-elision-iter-nrml-close.case
// - src/dstr-assignment-for-await/async-generator/async-gen-decl.template
/*---
description: IteratorClose is called when assignment evaluation has not exhausted 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 : [ Elision ]
1. Let iterator be ? GetIterator(value).
[...]
4. If iteratorRecord.[[Done]] is false, return ? IteratorClose(iterator, result)..
[...]
7.4.6 IteratorClose ( iterator, completion )
[...]
5. Let innerResult be Call(return, iterator, « »).
[...]
---*/
let nextCount = 0;
let returnCount = 0;
let thisValue = null;
let args = null;
let iterator = {
next() {
nextCount += 1;
// Set an upper-bound to limit unnecessary iteration in non-conformant
// implementations
return { done: nextCount > 10 };
},
return() {
returnCount += 1;
thisValue = this;
args = arguments;
return {};
}
};
let iterable = {
[Symbol.iterator]() {
return iterator;
}
};
let iterCount = 0;
async function * fn() {
for await ([ , ] of [iterable]) {
assert.sameValue(nextCount, 1);
assert.sameValue(returnCount, 1);
assert.sameValue(thisValue, iterator, 'correct `this` value');
assert(!!args, 'arguments object provided');
assert.sameValue(args.length, 0, 'zero arguments specified');
iterCount += 1;
}
}
let iter = fn();
iter.next()
.then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE)
.then($DONE, $DONE);