js/src/tests/test262/built-ins/Array/fromAsync/sync-iterable-with-thenable-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: >
  Sync-iterable input with thenables awaits each input once with async mapping callback.
includes: [asyncHelpers.js]
flags: [async]
features: [Array.fromAsync]
---*/

asyncTest(async function () {
  const expectedValue = {};
  let awaitCounter = 0;
  const inputThenable = {
    then (resolve, reject) {
      awaitCounter++;
      resolve(expectedValue);
    },
  };
  const input = [ inputThenable ].values();
  await Array.fromAsync(input, async v => v);
  assert.sameValue(awaitCounter, 1);
});