| // 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 Future<T> lastWhere (bool test(T element), |
| /// {@deprecated dynamic defaultValue(), T orElse()}) |
| /// |
| /// Finds the last element in this stream matching test. |
| /// |
| /// If this stream emits an error, the returned future is completed with that |
| /// error, and processing stops. |
| /// |
| /// Otherwise as firstWhere, except that the last matching element is found |
| /// instead of the first. That means that a non-error result cannot be provided |
| /// before this stream is done. |
| /// |
| /// The defaultValue parameter is deprecated, and orElse should be used instead. |
| /// @description Checks that if element is found, it is passed to the resulting |
| /// future. [orElse] is provided. |
| /// @author a.semenov@unipro.ru |
| |
| library lastWhere_A01_t02; |
| import "dart:async"; |
| import "../../../Utils/expect.dart"; |
| |
| void check<T>(Stream<T> s, bool test(T element), T expected) { |
| bool orElseCalled = false; |
| asyncStart(); |
| s.lastWhere(test, orElse:() { |
| orElseCalled = true; |
| return null as T; |
| }) |
| .then((T actual){ |
| Expect.equals(expected, actual); |
| Expect.isFalse(orElseCalled); |
| asyncEnd(); |
| }); |
| } |
| |
| void test(CreateStreamFunction create) { |
| check(create<int>([1, 2, 3]), (int element) => true, 3); |
| check(create<int?>([1, 2, 3]), (int? element) => element != null, 3); |
| check(create<int?>([1, 2, 3, null]), (int? element) => element == null, null); |
| check(create<int>([1, 2, 3]), (int element) => element > 0, 3); |
| check(create<int>(new Iterable<int>.generate(10, (int index) => index * 5)), |
| (int element) => element != 30, 45); |
| check(create<int>(new Iterable<int>.generate(10, (int index) => index * 5)), |
| (int element) => element == 30, 30); |
| } |