// 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 new Stream()
/// @description Checks that default constructor works.
/// @author kaigorodov


import "dart:async";

class MyStreamSubscription<T> extends StreamSubscription<T> {
  @override
  Future<E> asFuture<E>([E? futureValue]) {
  throw UnimplementedError();
  }
  @override
  Future<void> cancel() {
  throw UnimplementedError();
  }
  @override
  void onData(void Function(T data)? handleData) {
  }
  @override
  void onDone(void Function()? handleDone) {
  }
  @override
  void onError(Function? handleError) {
  }
  @override
  void pause([Future<void>? resumeSignal]) {
  }
  @override
  void resume() {
  }
  @override
  bool get isPaused => throw UnimplementedError();
}

class MyStream<T> extends Stream<T> {
  StreamSubscription<T> listen(void onData(T event)?,
                   {Function? onError, void onDone()?, bool? cancelOnError})
  {
    return new MyStreamSubscription();
  }
}

main() {
  new MyStream();
}