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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: >
Overwrites non-writable element properties on an instance of a custom
this-value
info: |
3.j.ii.8. Let _defineStatus_ be CreateDataPropertyOrThrow(_A_, _Pk_, _mappedValue_).
...
3.k.vii.6. Perform ? CreateDataPropertyOrThrow(_A_, _Pk_, _mappedValue_).
includes: [asyncHelpers.js]
flags: [async]
features: [Array.fromAsync]
---*/
asyncTest(async function () {
function MyArray() {
this.length = 4;
for (let ix = 0; ix < this.length; ix++) {
Object.defineProperty(this, ix, {
enumerable: true,
writable: false,
configurable: true,
value: 99
});
}
}
let result = await Array.fromAsync.call(MyArray, [0, 1, 2]);
assert.sameValue(result.length, 3, "Length property is overwritten");
assert.sameValue(result[0], 0, "Read-only element 0 is overwritten");
assert.sameValue(result[1], 1, "Read-only element 1 is overwritten");
assert.sameValue(result[2], 2, "Read-only element 2 is overwritten");
assert.sameValue(result[3], 99, "Element 3 is not overwritten");
result = await Array.fromAsync.call(MyArray, {
length: 3,
0: 0,
1: 1,
2: 2,
3: 3 // ignored
});
assert.sameValue(result.length, 3, "Length property is overwritten");
assert.sameValue(result[0], 0, "Read-only element 0 is overwritten");
assert.sameValue(result[1], 1, "Read-only element 1 is overwritten");
assert.sameValue(result[2], 2, "Read-only element 2 is overwritten");
assert.sameValue(result[3], 99, "Element 3 is not overwritten");
});