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// |reftest| async
// Copyright (C) 2023 Igalia, S.L. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-array.fromasync
description: >
An asynchronous mapping function is applied to each item yielded by a
synchronous iterable.
info: |
3.j.ii.6. If _mapping_ is *true*, then
a. Let _mappedValue_ be Call(_mapfn_, _thisArg_, « _nextValue_, 𝔽(_k_) »).
...
c. Set _mappedValue_ to Await(_mappedValue_).
...
...
8. Let _defineStatus_ be CreateDataPropertyOrThrow(_A_, _Pk_, _mappedValue_).
flags: [async]
includes: [asyncHelpers.js, compareArray.js]
features: [Array.fromAsync]
---*/
function* syncGen() {
for (let i = 0; i < 4; i++) {
yield i * 2;
}
}
async function asyncMap(val, ix) {
return Promise.resolve(val * ix);
}
asyncTest(async () => {
const result = await Array.fromAsync({ [Symbol.iterator]: syncGen }, asyncMap);
assert.compareArray(result, [0, 2, 8, 18], "async mapfn should be applied to sync iterable");
});