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.maybe;
  
  import static org.junit.Assert.*;
  
  import org.junit.Test;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.exceptions.TestException;
  import io.reactivex.rxjava3.functions.Function;
  import io.reactivex.rxjava3.internal.fuseable.HasUpstreamMaybeSource;
  import io.reactivex.rxjava3.observers.TestObserver;
  import io.reactivex.rxjava3.processors.PublishProcessor;
  import io.reactivex.rxjava3.testsupport.TestHelper;
  
  public class MaybeSwitchIfEmptySingleTest extends RxJavaTest {
  
      @Test
      public void nonEmpty() {
          Maybe.just(1).switchIfEmpty(Single.just(2)).test().assertResult(1);
      }
  
      @Test
      public void empty() {
          Maybe.<Integer>empty().switchIfEmpty(Single.just(2)).test().assertResult(2);
      }
  
      @Test
      public void error() {
          Maybe.<Integer>error(new TestException()).switchIfEmpty(Single.just(2))
          .test().assertFailure(TestException.class);
      }
  
      @Test
      public void errorOther() {
          Maybe.empty().switchIfEmpty(Single.<Integer>error(new TestException()))
          .test().assertFailure(TestException.class);
      }
  
      @Test
      public void dispose() {
          PublishProcessor<Integer> pp = PublishProcessor.create();
  
          TestObserver<Integer> to = pp.singleElement().switchIfEmpty(Single.just(2)).test();
  
          assertTrue(pp.hasSubscribers());
  
          to.dispose();
  
          assertFalse(pp.hasSubscribers());
      }
  
      @Test
      public void isDisposed() {
          PublishProcessor<Integer> pp = PublishProcessor.create();
  
          TestHelper.checkDisposed(pp.singleElement().switchIfEmpty(Single.just(2)));
      }
  
      @Test
      public void doubleOnSubscribe() {
          TestHelper.checkDoubleOnSubscribeMaybeToSingle(new Function<Maybe<Integer>, Single<Integer>>() {
              @Override
              public Single<Integer> apply(Maybe<Integer> f) throws Exception {
                  return f.switchIfEmpty(Single.just(2));
              }
          });
      }
  
      @Test
      public void emptyCancelRace() {
          for (int i = 0; i < TestHelper.RACE_DEFAULT_LOOPS; i++) {
              final PublishProcessor<Integer> pp = PublishProcessor.create();
  
              final TestObserver<Integer> to = pp.singleElement().switchIfEmpty(Single.just(2)).test();
  
              Runnable r1 = new Runnable() {
                  @Override
                  public void run() {
                      pp.onComplete();
                  }
              };
  
              Runnable r2 = new Runnable() {
                  @Override
                  public void run() {
                      to.dispose();
                  }
              };
  
              TestHelper.race(r1, r2);
          }
      }
  
      @SuppressWarnings("rawtypes")
      @Test
      public void source() {
          assertSame(Maybe.empty(),
                  ((HasUpstreamMaybeSource)(Maybe.<Integer>empty().switchIfEmpty(Single.just(1)))).source()
          );
      }
  }
  