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// Copyright (C) 2017 André Bargull. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-runtime-semantics-forin-div-ofbodyevaluation-lhs-stmt-iterator-lhskind-labelset
description: >
Iterators should be closed via their `return` method when iteration is
interrupted via a `continue` statement.
info: |
13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation ( lhs, stmt, iteratorRecord, iterationKind, lhsKind, labelSet )
...
5. Repeat,
...
i. Let result be the result of evaluating stmt.
...
k. If LoopContinues(result, labelSet) is false, then
i. If iterationKind is enumerate, then
...
ii. Else,
1. Assert: iterationKind is iterate.
2. Return ? IteratorClose(iteratorRecord, UpdateEmpty(result, V)).
...
features: [Symbol.iterator]
---*/
var startedCount = 0;
var returnCount = 0;
var iterationCount = 0;
var iterable = {};
iterable[Symbol.iterator] = function() {
return {
next: function() {
startedCount += 1;
return { done: false, value: null };
},
return: function() {
returnCount += 1;
return {};
}
};
};
L: do {
for (var x of iterable) {
assert.sameValue(
startedCount, 1, 'Value is retrieved'
);
assert.sameValue(
returnCount, 0, 'Iterator is not closed'
);
iterationCount += 1;
continue L;
}
} while (false);
assert.sameValue(
startedCount, 1, 'Iterator does not restart following interruption'
);
assert.sameValue(iterationCount, 1, 'A single iteration occurs');
assert.sameValue(
returnCount, 1, 'Iterator is closed after `continue` statement'
);
reportCompare(0, 0);