| // Copyright (c) 2024, 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. |
| |
| import "package:expect/async_helper.dart"; |
| import "package:expect/expect.dart"; |
| |
| Stream<String> stream() async* { |
| yield 'a'; |
| yield 'b'; |
| } |
| |
| Stream<String> expandedStream() async* { |
| final expanded = stream().asyncExpand((s) async* { |
| yield 'before'; |
| yield s; |
| yield 'after'; |
| }); |
| |
| yield* expanded; |
| } |
| |
| Future test() async { |
| Expect.listEquals([ |
| 'before', |
| 'a', |
| 'after', |
| 'before', |
| 'b', |
| 'after', |
| ], await expandedStream().toList()); |
| } |
| |
| void main() { |
| asyncStart(); |
| test().then((_) => asyncEnd()); |
| } |