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// Copyright (C) 2013 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-getiterator
description: >
The iterator's `next` method should be accessed only once with each
iteration as per the `GetIterator` abstract operation (7.4.1).
features: [Symbol.iterator, for-of]
---*/
var iterable = {};
var iterator = {};
var iterationCount = 0;
var loadNextCount = 0;
iterable[Symbol.iterator] = function() {
return iterator;
};
function next() {
if (iterationCount) return { done: true };
return { value: 45, done: false };
}
Object.defineProperty(iterator, 'next', {
get() { loadNextCount++; return next; },
configurable: true
});
for (var x of iterable) {
assert.sameValue(x, 45);
Object.defineProperty(iterator, 'next', {
get: function() {
throw new Test262Error(
'Should not access the `next` method after the iteration prologue.');
}
});
iterationCount++;
}
assert.sameValue(iterationCount, 1);
assert.sameValue(loadNextCount, 1);
reportCompare(0, 0);