js/src/tests/test262/built-ins/Array/fromAsync/async-iterable-async-mapped-awaits-once.js


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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: >
  Async-iterable awaits each input once with mapping callback
includes: [asyncHelpers.js]
flags: [async]
features: [Array.fromAsync]
---*/

asyncTest(async function () {
  async function* generateInput () {
    yield* [ 0, 1, 2 ];
  }
  const input = generateInput();
  let awaitCounter = 0;
  await Array.fromAsync(input, v => {
    return {
      // This “then” method should occur three times:
      // one for each value from the input.
      then (resolve, reject) {
        awaitCounter ++;
        resolve(v);
      },
    };
  });
  assert.sameValue(awaitCounter, 3);
});