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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
desc: >
IteratorClose is invoked when evaluation of AssignmentElementList returns
a "return" completion and the iterator has not been marked as "done"
info: |
ArrayAssignmentPattern :
[ AssignmentElementList , Elisionopt AssignmentRestElementopt ]
[...]
3. Let iteratorRecord be Record {[[iterator]]: iterator, [[done]]: false}.
4. Let status be the result of performing
IteratorDestructuringAssignmentEvaluation of AssignmentElementList using
iteratorRecord as the argument.
5. If status is an abrupt completion, then
a. If iteratorRecord.[[done]] is false, return IteratorClose(iterator,
status).
7.4.6 IteratorClose( iterator, completion )
[...]
6. Let innerResult be Call(return, iterator, « »).
7. If completion.[[type]] is throw, return Completion(completion).
8. If innerResult.[[type]] is throw, return Completion(innerResult).
features: [Symbol.iterator, generators]
template: default
es6id: 12.14.5.2
esid: sec-runtime-semantics-destructuringassignmentevaluation
---*/
//- setup
var nextCount = 0;
var returnCount = 0;
var unreachable = 0;
var iterator = {
next: function() {
nextCount += 1;
return {done: false, value: undefined};
},
return: function() {
returnCount += 1;
throw new Test262Error();
}
};
var iterable = {};
iterable[Symbol.iterator] = function() {
return iterator;
};
function* g() {
//- elems
[ {} = yield , ]
//- vals
iterable
//- body
unreachable += 1;
//- teardown
}
var iter = g();
iter.next();
assert.sameValue(nextCount, 1);
assert.sameValue(returnCount, 0);
assert.throws(Test262Error, function() {
iter.return();
});
assert.sameValue(nextCount, 1);
assert.sameValue(returnCount, 1);
assert.sameValue(unreachable, 0, 'Unreachable statement was not executed');
|