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.assertTrue;
  
  import java.util.List;
  
  import org.junit.Test;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.disposables.*;
  import io.reactivex.rxjava3.exceptions.TestException;
  import io.reactivex.rxjava3.functions.*;
  import io.reactivex.rxjava3.plugins.RxJavaPlugins;
  import io.reactivex.rxjava3.subjects.PublishSubject;
  import io.reactivex.rxjava3.testsupport.TestHelper;
  
  public class MaybeDoOnEventTest extends RxJavaTest {
  
      @Test
      public void dispose() {
          TestHelper.checkDisposed(PublishSubject.<Integer>create().singleElement().doOnEvent(new BiConsumer<Integer, Throwable>() {
              @Override
              public void accept(Integer v, Throwable e) throws Exception {
                  // irrelevant
              }
          }));
      }
  
      @Test
      public void doubleOnSubscribe() {
          TestHelper.checkDoubleOnSubscribeMaybe(new Function<Maybe<Integer>, MaybeSource<Integer>>() {
              @Override
              public MaybeSource<Integer> apply(Maybe<Integer> m) throws Exception {
                  return m.doOnEvent(new BiConsumer<Integer, Throwable>() {
                      @Override
                      public void accept(Integer v, Throwable e) throws Exception {
                          // irrelevant
                      }
                  });
              }
          });
      }
  
      @Test
      public void onSubscribeCrash() {
          List<Throwable> errors = TestHelper.trackPluginErrors();
          try {
              final Disposable bs = Disposable.empty();
  
              new Maybe<Integer>() {
                  @Override
                  protected void subscribeActual(MaybeObserver<? super Integer> observer) {
                      observer.onSubscribe(bs);
                      observer.onError(new TestException("Second"));
                      observer.onComplete();
                      observer.onSuccess(1);
                  }
              }
              .doOnSubscribe(new Consumer<Disposable>() {
                  @Override
                  public void accept(Disposable d) throws Exception {
                      throw new TestException("First");
                  }
              })
              .to(TestHelper.<Integer>testConsumer())
              .assertFailureAndMessage(TestException.class, "First");
  
              assertTrue(bs.isDisposed());
  
              TestHelper.assertUndeliverable(errors, 0, TestException.class, "Second");
          } finally {
              RxJavaPlugins.reset();
          }
      }
  }
  