LibTest/async/Future/Future_A01_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(dynamic computation())
 * Creates a future containing the result of calling computation
 * asynchronously with Timer.run.
 * If the result of executing computation throws, the returned future is
 * completed with the error.
 * If the returned value is itself a Future, completion of the created
 * future will wait until the returned future completes, and will then
 * complete with the same result.
 * If a non-future value is returned, the returned future is completed with
 * that value.
 * @description Checks that computation() is run asynchronously.
 * @author ilya
 */
import "dart:async";
import "../../../Utils/expect.dart";

main() {
  var x = 42;
  asyncStart();
  Future<int> i = new Future(() {
    new Future.delayed(new Duration(seconds: 1)).then((_) {
      x = 1;
      asyncEnd();
      return 0;
    });
    return 2;
  });
  Expect.equals(42, x);
}