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// Copyright (C) 2017 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
desc: IteratorClose invoked when elision does not exhaust the iterator
info: |
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).
7.4.6 IteratorClose ( iterator, completion )
[...]
5. Let innerResult be Call(return, iterator, « »).
[...]
features: [Symbol.iterator]
template: async-generator
esid: sec-runtime-semantics-destructuringassignmentevaluation
---*/
//- setup
let nextCount = 0;
let returnCount = 0;
let thisValue = null;
let args = null;
let x;
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;
}
};
//- elems
[ x , , ]
//- vals
iterable
//- body
assert.sameValue(nextCount, 2);
assert.sameValue(returnCount, 1);
assert.sameValue(thisValue, iterator, 'correct `this` value');
assert(!!args, 'arguments object provided');
assert.sameValue(args.length, 0, 'zero arguments specified');
//- teardown
iter.next()
.then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE)
.then($DONE, $DONE);
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