// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

// @dart = 2.9

/// @assertion  Stream asyncMap(dynamic convert(T event))
/// Creates a new stream with each data event of this stream asynchronously
/// mapped to a new event.
///
/// This acts like map, except that convert may return a Future, and in that
/// case, the stream waits for that future to complete before continuing with
/// its result.
///
/// @description Checks that if convert return a Future, the stream waits for
/// that future to complete before continuing with its result.
/// @author a.semenov@unipro.ru

library asyncMap_A01_t04;
import "dart:async";
import "../../../Utils/expect.dart";

void check<T>(Stream<T> stream, List<T> expected) {
  AsyncExpect.data(
      expected,
      stream.asyncMap((e) => new Future.delayed(durationMs(50), () => e))
  );
}

void test(CreateStreamFunction create) {
  check(create([]), []);
  check(create([1, 2, 3, 4]), [1, 2, 3, 4]);
  check(create([null, "2", -3, 4.0, []]), [null, "2", -3, 4.0, []]);
}