LibTest/async/Future/whenComplete_A04_t01.dart

// Copyright (c) 2011, 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.

/// @assertion Future<T> whenComplete(action())
/// If the call to action returns a Future, f2, then completion of f is delayed
/// until f2 completes. If f2 completes with an error, that will be the result
/// of f too.
/// @description Checks that if the call to action returns a Future, f2, then
/// completion of f is delayed until f2 completes.
/// @author kaigorodov

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

main() {
  int value = 20;

  Completer completer = new Completer();
  Future f0 = completer.future;

  Completer completer2 = new Completer();
  Future f2 = completer2.future;

  Future f = f0.whenComplete(() => f2);

  asyncStart();
  completer.complete(value);
  f.then((value2) {
    Expect.equals(value, value2);
    asyncEnd();
  });

  completer2.complete(1);
}