| // 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. |
| |
| // @dart = 2.9 |
| |
| /// @assertion Stream<T> distinct([bool equals(T previous, T next)]) |
| /// Skips data events if they are equal to the previous data event. |
| /// The returned stream provides the same events as this stream, except that it |
| /// never provides two consecutive data events that are equal. |
| /// @description Checks that errors in original stream are copied to the returned |
| /// stream. [equals] is provided. |
| /// @issue #29627 |
| /// @author a.semenov@unipro.ru |
| |
| library distinct_A04_t02; |
| import "dart:async"; |
| import "../../../Utils/expect.dart"; |
| |
| void check<T>(Stream<T> s, List<T> expectedData, List expectedErrors) { |
| AsyncExpect.events(expectedData, expectedErrors, s.distinct((p,n) => p==n)); |
| } |
| |
| void test(CreateStreamWithErrorsFunction create) { |
| check(create([]), [], []); |
| check(create([1, 2, 2, 3], isError:(e) => e.isEven), [1,3],[2,2]); |
| check(create([1, 1, 2, 2, 3, 3], isError:(e) => e.isEven), [1,3],[2,2]); |
| check(create([1, 1, 2, 2, 3, 3], isError:(e) => e.isOdd), [2],[1,1,3,3]); |
| check(create([1, 2, null, null], isError:(e) => e is num), [null], [1,2]); |
| } |