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 java.util.*;
  import java.util.concurrent.*;
  import java.util.concurrent.atomic.AtomicBoolean;
  
  import io.reactivex.rxjava3.disposables.Disposable;
  import org.junit.Test;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.exceptions.TestException;
  import io.reactivex.rxjava3.functions.*;
  import io.reactivex.rxjava3.internal.functions.Functions;
  import io.reactivex.rxjava3.observers.TestObserver;
  import io.reactivex.rxjava3.plugins.RxJavaPlugins;
  import io.reactivex.rxjava3.processors.PublishProcessor;
  import io.reactivex.rxjava3.schedulers.Schedulers;
  import io.reactivex.rxjava3.subjects.*;
  import io.reactivex.rxjava3.testsupport.TestHelper;
  
  public class MaybeAmbTest extends RxJavaTest {
  
      @Test
      public void ambLots() {
          List<Maybe<Integer>> ms = new ArrayList<>();
  
          for (int i = 0; i < 32; i++) {
              ms.add(Maybe.<Integer>never());
          }
  
          ms.add(Maybe.just(1));
  
          Maybe.amb(ms)
          .test()
          .assertResult(1);
      }
  
      @Test
      public void ambFirstDone() {
          Maybe.amb(Arrays.asList(Maybe.just(1), Maybe.just(2)))
          .test()
          .assertResult(1);
      }
  
      @Test
      public void dispose() {
          PublishProcessor<Integer> pp1 = PublishProcessor.create();
          PublishProcessor<Integer> pp2 = PublishProcessor.create();
  
          TestObserver<Integer> to = Maybe.amb(Arrays.asList(pp1.singleElement(), pp2.singleElement()))
          .test();
  
          assertTrue(pp1.hasSubscribers());
          assertTrue(pp2.hasSubscribers());
  
          to.dispose();
  
          assertFalse(pp1.hasSubscribers());
          assertFalse(pp2.hasSubscribers());
      }
  
      @Test
      public void innerErrorRace() {
          for (int i = 0; i < TestHelper.RACE_DEFAULT_LOOPS; i++) {
              List<Throwable> errors = TestHelper.trackPluginErrors();
              try {
                  final PublishProcessor<Integer> pp0 = PublishProcessor.create();
                  final PublishProcessor<Integer> pp1 = PublishProcessor.create();
  
                  final TestObserver<Integer> to = Maybe.amb(Arrays.asList(pp0.singleElement(), pp1.singleElement()))
                  .test();
  
                  final TestException ex = new TestException();
  
                  Runnable r1 = new Runnable() {
                      @Override
                      public void run() {
                          pp0.onError(ex);
                      }
                  };
  
                  Runnable r2 = new Runnable() {
                      @Override
                      public void run() {
                          pp1.onError(ex);
                      }
                  };
  
                  TestHelper.race(r1, r2);
  
                  to.assertFailure(TestException.class);
  
                  if (!errors.isEmpty()) {
                      TestHelper.assertUndeliverable(errors, 0, TestException.class);
                  }
              } finally {
                  RxJavaPlugins.reset();
              }
          }
      }
  
      @Test
      public void disposeNoFurtherSignals() {
          TestObserver<Integer> to = Maybe.ambArray(new Maybe<Integer>() {
              @Override
              protected void subscribeActual(
                      MaybeObserver<? super Integer> observer) {
                  observer.onSubscribe(Disposable.empty());
                  observer.onSuccess(1);
                  observer.onSuccess(2);
                  observer.onComplete();
              }
          }, Maybe.<Integer>never())
          .test();
  
          to.dispose();
  
          to.assertResult(1);
      }
  
      @Test
      public void noWinnerSuccessDispose() throws Exception {
          for (int i = 0; i < TestHelper.RACE_LONG_LOOPS; i++) {
              final AtomicBoolean interrupted = new AtomicBoolean();
              final CountDownLatch cdl = new CountDownLatch(1);
  
              Maybe.ambArray(
                  Maybe.just(1)
                      .subscribeOn(Schedulers.single())
                      .observeOn(Schedulers.computation()),
                  Maybe.never()
              )
              .subscribe(new Consumer<Object>() {
                  @Override
                  public void accept(Object v) throws Exception {
                      interrupted.set(Thread.currentThread().isInterrupted());
                      cdl.countDown();
                  }
              });
  
              assertTrue(cdl.await(500, TimeUnit.SECONDS));
              assertFalse("Interrupted!", interrupted.get());
          }
      }
  
      @Test
      public void noWinnerErrorDispose() throws Exception {
          final TestException ex = new TestException();
          for (int i = 0; i < TestHelper.RACE_LONG_LOOPS; i++) {
              final AtomicBoolean interrupted = new AtomicBoolean();
              final CountDownLatch cdl = new CountDownLatch(1);
  
              Maybe.ambArray(
                  Maybe.error(ex)
                      .subscribeOn(Schedulers.single())
                      .observeOn(Schedulers.computation()),
                  Maybe.never()
              )
              .subscribe(Functions.emptyConsumer(), new Consumer<Throwable>() {
                  @Override
                  public void accept(Throwable e) throws Exception {
                      interrupted.set(Thread.currentThread().isInterrupted());
                      cdl.countDown();
                  }
              });
  
              assertTrue(cdl.await(500, TimeUnit.SECONDS));
              assertFalse("Interrupted!", interrupted.get());
          }
      }
  
      @Test
      public void noWinnerCompleteDispose() throws Exception {
          for (int i = 0; i < TestHelper.RACE_LONG_LOOPS; i++) {
              final AtomicBoolean interrupted = new AtomicBoolean();
              final CountDownLatch cdl = new CountDownLatch(1);
  
              Maybe.ambArray(
                  Maybe.empty()
                      .subscribeOn(Schedulers.single())
                      .observeOn(Schedulers.computation()),
                  Maybe.never()
              )
              .subscribe(Functions.emptyConsumer(), Functions.emptyConsumer(), new Action() {
                  @Override
                  public void run() throws Exception {
                      interrupted.set(Thread.currentThread().isInterrupted());
                      cdl.countDown();
                  }
              });
  
              assertTrue(cdl.await(500, TimeUnit.SECONDS));
              assertFalse("Interrupted!", interrupted.get());
          }
      }
  
      @Test
      public void nullSourceSuccessRace() {
          for (int i = 0; i < TestHelper.RACE_DEFAULT_LOOPS; i++) {
              List<Throwable> errors = TestHelper.trackPluginErrors();
  
              try {
  
                  final Subject<Integer> ps = ReplaySubject.create();
                  ps.onNext(1);
  
                  final Maybe<Integer> source = Maybe.ambArray(ps.singleElement(),
                          Maybe.<Integer>never(), Maybe.<Integer>never(), null);
  
                  Runnable r1 = new Runnable() {
                      @Override
                      public void run() {
                          source.test();
                      }
                  };
  
                  Runnable r2 = new Runnable() {
                      @Override
                      public void run() {
                          ps.onComplete();
                      }
                  };
  
                  TestHelper.race(r1, r2);
  
                  if (!errors.isEmpty()) {
                      TestHelper.assertError(errors, 0, NullPointerException.class);
                  }
              } finally {
                  RxJavaPlugins.reset();
              }
          }
      }
  
      @Test
      public void maybeSourcesInIterable() {
          MaybeSource<Integer> source = new MaybeSource<Integer>() {
              @Override
              public void subscribe(MaybeObserver<? super Integer> observer) {
                  Maybe.just(1).subscribe(observer);
              }
          };
  
          Maybe.amb(Arrays.asList(source, source))
          .test()
          .assertResult(1);
      }
  }
  