code: /*
   * Copyright (c) 2016-present, RxJava Contributors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
   * compliance with the License. You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software distributed under the License is
   * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
   * the License for the specific language governing permissions and limitations under the License.
   */
  
  package io.reactivex.rxjava3.internal.operators.observable;
  
  import static org.mockito.ArgumentMatchers.any;
  import static org.mockito.Mockito.*;
  
  import org.junit.Test;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.testsupport.TestHelper;
  
  public class ObservableDefaultIfEmptyTest extends RxJavaTest {
  
      @Test
      public void defaultIfEmpty() {
          Observable<Integer> source = Observable.just(1, 2, 3);
          Observable<Integer> observable = source.defaultIfEmpty(10);
  
          Observer<Integer> observer = TestHelper.mockObserver();
  
          observable.subscribe(observer);
  
          verify(observer, never()).onNext(10);
          verify(observer).onNext(1);
          verify(observer).onNext(2);
          verify(observer).onNext(3);
          verify(observer).onComplete();
          verify(observer, never()).onError(any(Throwable.class));
      }
  
      @Test
      public void defaultIfEmptyWithEmpty() {
          Observable<Integer> source = Observable.empty();
          Observable<Integer> observable = source.defaultIfEmpty(10);
  
          Observer<Integer> observer = TestHelper.mockObserver();
  
          observable.subscribe(observer);
  
          verify(observer).onNext(10);
          verify(observer).onComplete();
          verify(observer, never()).onError(any(Throwable.class));
      }
  }
  