Bug 271703 – Array.fromAsync calls Array constructor twice

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Sosuke Suzuki]

When executing `Array.fromAsync.call(MyArray, { length: 2, 0: 1, 1: 2 });`, the `MyArray` constructor is called twice by `Array.fromAsync`.
This bug is the cause of the failure of the Array.fromAsync test case in test262 (ref: https://github.com/WebKit/WebKit/blob/d03ff2b610bca99b7a8160d654e35297218ff64a/JSTests/test262/expectations.yaml#L4-L9).

poc:
```js
function shouldBe(actual, expected) {
  if (actual !== expected) throw new Error("bad value: " + actual);
}

let callCount = 0;

function MyArray(...args) {
  callCount++;
  return new Proxy(Object.create(null), {
    set(target, key, value) {
      return Reflect.set(target, key, value);
    },
    defineProperty(target, key, descriptor) {
      return Reflect.defineProperty(target, key, descriptor);
    },
  });
}

(async () => {
  await Array.fromAsync.call(MyArray, { length: 2, 0: 1, 1: 2 });
})().then(() => {
  shouldBe(callCount, 1);
});
```

[Sosuke Suzuki]

Pull request: https://github.com/WebKit/WebKit/pull/26459

[EWS]

Committed 276752@main (75d98d9e2d74): <https://commits.webkit.org/276752@main>

Reviewed commits have been landed. Closing PR #26459 and removing active labels.

[Radar WebKit Bug Importer]

<rdar://problem/125509304>