| // Copyright (c) 2012, 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 |
| |
| // Regression test for http://dartbug.com/7964 |
| |
| library first_regression_test; |
| |
| import 'dart:async'; |
| |
| class DoubleTransformer<T> extends StreamTransformerBase<T, T> { |
| Stream<T> bind(Stream<T> stream) { |
| var transformer = new StreamTransformer<T, T>.fromHandlers( |
| handleData: (T data, EventSink<T> sink) { |
| sink.add(data); |
| sink.add(data); |
| }); |
| return transformer.bind(stream); |
| } |
| } |
| |
| main() async { |
| // This should not crash. Did crash by trying to complete future more |
| // than once. |
| await (new Stream.fromIterable([1, 2]).transform(new DoubleTransformer())) |
| .first; |
| } |