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// |reftest| skip-if(!this.hasOwnProperty('AsyncIterator'))
//
//
/*---
esid: pending
description: %AsyncIterator.prototype% methods ignore iterator mutation if already done.
info: >
Iterator Helpers proposal 2.1.6
features: [iterator-helpers]
---*/
class TestIterator extends AsyncIterator {
values = [1, 2];
async next() {
if (this.values.length == 0)
return {done: true};
return {done: false, value: this.values.shift()};
}
}
function check({done, value}, expectedDone, expectedValue) {
assertEq(done, expectedDone);
assertEq(Array.isArray(value) ? value[1] : value, expectedValue);
}
const methods = [
['map', x => x],
['filter', x => true],
['take', Infinity],
['drop', 0],
['asIndexedPairs', undefined],
['flatMap', async function*(x) { yield x; }],
];
for (const [method, arg] of methods) {
(async () => {
const iter = new TestIterator();
const iterHelper = iter[method](arg);
check(await iterHelper.next(), false, 1);
check(await iterHelper.next(), false, 2);
check(await iterHelper.next(), true, undefined);
iter.values.push(3);
check(await iterHelper.next(), true, undefined);
})();
}
if (typeof reportCompare == 'function')
reportCompare(0, 0);
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