| /* |
| * Copyright (c) 2017, 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 abstract E singleWhere(bool test(E value)) |
| * Otherwise, if there are no matching elements, or if there is more than one |
| * matching element, a [StateError] is thrown. |
| * @description Checks that a [StateError] is thrown if no element match. |
| * @author kaigorodov |
| */ |
| import "dart:collection"; |
| import "../../../Utils/expect.dart"; |
| |
| class MyIterable<int> extends Object with IterableMixin { |
| List _content; |
| MyIterable(List list): _content = list; |
| |
| Iterator get iterator { |
| return _content.iterator; |
| } |
| } |
| |
| check(List a, bool test(value)) { |
| IterableMixin iterable = new MyIterable(a); |
| Expect.throws(() { iterable.singleWhere(test); }, (e) => e is StateError); |
| } |
| |
| main() { |
| check([ 1, 2, -3, 4], (value) => value == 0); |
| check(const[1, 2, -5, -6], (value) => value > 2); |
| } |