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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 (awaited) item of an
arraylike.
info: |
3.k.vii.4. If _mapping_ is *true*, then
a. Let _mappedValue_ be ? Call(_mapfn_, _thisArg_, « _nextValue_, 𝔽(_k_) »).
b. Let _mappedValue_ be ? Await(_mappedValue_).
...
6. Perform ? CreateDataPropertyOrThrow(_A_, _Pk_, _mappedValue_).
flags: [async]
includes: [asyncHelpers.js, compareArray.js]
features: [Array.fromAsync]
---*/
const arrayLike = {
length: 4,
0: 0,
1: 2,
2: Promise.resolve(4),
3: 6,
};
async function asyncMap(val, ix) {
return Promise.resolve(val * ix);
}
asyncTest(async () => {
const result = await Array.fromAsync(arrayLike, asyncMap);
assert.compareArray(result, [0, 2, 8, 18], "async mapfn should be applied to arraylike");
});