| // 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 Stream<T> asBroadcastStream ( |
| /// {void onListen(StreamSubscription<T> subscription), |
| /// void onCancel(StreamSubscription<T> subscription)}) |
| /// Returns a multi-subscription stream that produces the same events as this. |
| /// |
| /// The returned stream will subscribe to this stream when its first subscriber |
| /// is added, and will stay subscribed until this stream ends, or a callback |
| /// cancels the subscription. |
| /// |
| /// @description Checks that returned stream will subscribe to this stream |
| /// when its first subscriber is added. |
| /// @author a.semenov@unipro.ru |
| |
| import "dart:async"; |
| import "../../../Utils/expect.dart"; |
| |
| main() { |
| bool hasListener = false; |
| StreamController controller = new StreamController( |
| onListen:(){ hasListener = true;} |
| ); |
| Stream b = controller.stream.asBroadcastStream(); |
| Expect.isFalse(hasListener); |
| asyncMultiStart(2); |
| b.listen( |
| (_) { |
| Expect.isTrue(hasListener); |
| asyncEnd(); |
| } |
| ); |
| b.listen( |
| (_) { |
| Expect.isTrue(hasListener); |
| asyncEnd(); |
| } |
| ); |
| Expect.isTrue(hasListener); |
| controller.add("a"); |
| new Future(() => controller.close()); |
| } |