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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: >
The returned value from each invocation of the asynchronous mapping function
is awaited exactly once.
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_).
flags: [async]
includes: [asyncHelpers.js, compareArray.js, temporalHelpers.js]
features: [Array.fromAsync]
---*/
const calls = [];
const expected = [
"call mapping",
"get thenable_0.then",
"call thenable_0.then",
"call mapping",
"get thenable_1.then",
"call thenable_1.then",
"call mapping",
"get thenable_2.then",
"call thenable_2.then",
];
function mapping(val, ix) {
calls.push("call mapping");
const thenableName = `thenable_${ix}`;
return TemporalHelpers.propertyBagObserver(calls, {
then(resolve, reject) {
calls.push(`call ${thenableName}.then`);
resolve(val * 2);
}
}, thenableName)
}
asyncTest(async () => {
const result = await Array.fromAsync([1, 2, 3], mapping);
assert.compareArray(result, [2, 4, 6], "mapping function applied");
assert.compareArray(calls, expected, "observable operations");
});