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// |reftest| shell-option(--enable-array-from-async) skip-if(!Array.fromAsync||!xulRuntime.shell) async -- Array.fromAsync is not enabled unconditionally, requires shell-options
// 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: >
A synchronous mapping function is applied to each item yielded by an
asynchronous iterable.
info: |
3.j.ii.6. If _mapping_ is *true*, then
a. Let _mappedValue_ be Call(_mapfn_, _thisArg_, « _nextValue_, 𝔽(_k_) »).
...
...
8. Let _defineStatus_ be CreateDataPropertyOrThrow(_A_, _Pk_, _mappedValue_).
flags: [async]
includes: [asyncHelpers.js, compareArray.js]
features: [Array.fromAsync]
---*/
async function* asyncGen() {
for (let i = 0; i < 4; i++) {
yield Promise.resolve(i * 2);
}
}
function syncMap(val, ix) {
return val * ix;
}
asyncTest(async () => {
const result = await Array.fromAsync({ [Symbol.asyncIterator]: asyncGen }, syncMap);
assert.compareArray(result, [0, 2, 8, 18], "sync mapfn should be applied to async iterable");
});
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