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.junit.Assert.*;
  
  import java.util.List;
  import java.util.concurrent.*;
  
  import org.junit.Test;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.disposables.*;
  import io.reactivex.rxjava3.exceptions.*;
  import io.reactivex.rxjava3.functions.Function;
  import io.reactivex.rxjava3.observers.TestObserver;
  import io.reactivex.rxjava3.operators.QueueDisposable;
  import io.reactivex.rxjava3.operators.QueueFuseable;
  import io.reactivex.rxjava3.schedulers.Schedulers;
  import io.reactivex.rxjava3.subjects.PublishSubject;
  import io.reactivex.rxjava3.testsupport.*;
  
  public class ObservableFlatMapCompletableTest extends RxJavaTest {
  
      @Test
      public void normalObservable() {
          Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          }).toObservable()
          .test()
          .assertResult();
      }
  
      @Test
      public void mapperThrowsObservable() {
          PublishSubject<Integer> ps = PublishSubject.create();
  
          TestObserver<Integer> to = ps
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  throw new TestException();
              }
          }).<Integer>toObservable()
          .test();
  
          assertTrue(ps.hasObservers());
  
          ps.onNext(1);
  
          to.assertFailure(TestException.class);
  
          assertFalse(ps.hasObservers());
      }
  
      @Test
      public void mapperReturnsNullObservable() {
          PublishSubject<Integer> ps = PublishSubject.create();
  
          TestObserver<Integer> to = ps
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return null;
              }
          }).<Integer>toObservable()
          .test();
  
          assertTrue(ps.hasObservers());
  
          ps.onNext(1);
  
          to.assertFailure(NullPointerException.class);
  
          assertFalse(ps.hasObservers());
      }
  
      @Test
      public void normalDelayErrorObservable() {
          Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          }, true).toObservable()
          .test()
          .assertResult();
      }
  
      @Test
      public void normalAsyncObservable() {
          Observable.range(1, 1000)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Observable.range(1, 100).subscribeOn(Schedulers.computation()).ignoreElements();
              }
          }).toObservable()
          .test()
          .awaitDone(5, TimeUnit.SECONDS)
          .assertResult();
      }
  
      @Test
      public void normalDelayErrorAllObservable() {
          TestObserverEx<Integer> to = Observable.range(1, 10).concatWith(Observable.<Integer>error(new TestException()))
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.error(new TestException());
              }
          }, true).<Integer>toObservable()
          .to(TestHelper.<Integer>testConsumer())
          .assertFailure(CompositeException.class);
  
          List<Throwable> errors = TestHelper.compositeList(to.errors().get(0));
  
          for (int i = 0; i < 11; i++) {
              TestHelper.assertError(errors, i, TestException.class);
          }
      }
  
      @Test
      public void normalDelayInnerErrorAllObservable() {
          TestObserverEx<Integer> to = Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.error(new TestException());
              }
          }, true).<Integer>toObservable()
          .to(TestHelper.<Integer>testConsumer())
          .assertFailure(CompositeException.class);
  
          List<Throwable> errors = TestHelper.compositeList(to.errors().get(0));
  
          for (int i = 0; i < 10; i++) {
              TestHelper.assertError(errors, i, TestException.class);
          }
      }
  
      @Test
      public void normalNonDelayErrorOuterObservable() {
          Observable.range(1, 10).concatWith(Observable.<Integer>error(new TestException()))
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          }, false).toObservable()
          .test()
          .assertFailure(TestException.class);
      }
  
      @Test
      public void fusedObservable() {
          TestObserverEx<Integer> to = new TestObserverEx<>(QueueFuseable.ANY);
  
          Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          }).<Integer>toObservable()
          .subscribe(to);
  
          to
          .assertFuseable()
          .assertFusionMode(QueueFuseable.ASYNC)
          .assertResult();
      }
  
      @Test
      public void disposedObservable() {
          TestHelper.checkDisposed(Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          }).toObservable());
      }
  
      @Test
      public void normal() {
          Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          })
          .test()
          .assertResult();
      }
  
      @Test
      public void mapperThrows() {
          PublishSubject<Integer> ps = PublishSubject.create();
  
          TestObserver<Void> to = ps
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  throw new TestException();
              }
          })
          .test();
  
          assertTrue(ps.hasObservers());
  
          ps.onNext(1);
  
          to.assertFailure(TestException.class);
  
          assertFalse(ps.hasObservers());
      }
  
      @Test
      public void mapperReturnsNull() {
          PublishSubject<Integer> ps = PublishSubject.create();
  
          TestObserver<Void> to = ps
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return null;
              }
          })
          .test();
  
          assertTrue(ps.hasObservers());
  
          ps.onNext(1);
  
          to.assertFailure(NullPointerException.class);
  
          assertFalse(ps.hasObservers());
      }
  
      @Test
      public void normalDelayError() {
          Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          }, true)
          .test()
          .assertResult();
      }
  
      @Test
      public void normalAsync() {
          Observable.range(1, 1000)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Observable.range(1, 100).subscribeOn(Schedulers.computation()).ignoreElements();
              }
          })
          .test()
          .awaitDone(5, TimeUnit.SECONDS)
          .assertResult();
      }
  
      @Test
      public void normalDelayErrorAll() {
          TestObserverEx<Void> to = Observable.range(1, 10).concatWith(Observable.<Integer>error(new TestException()))
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.error(new TestException());
              }
          }, true)
          .to(TestHelper.<Void>testConsumer())
          .assertFailure(CompositeException.class);
  
          List<Throwable> errors = TestHelper.compositeList(to.errors().get(0));
  
          for (int i = 0; i < 11; i++) {
              TestHelper.assertError(errors, i, TestException.class);
          }
      }
  
      @Test
      public void normalDelayInnerErrorAll() {
          TestObserverEx<Void> to = Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.error(new TestException());
              }
          }, true)
          .to(TestHelper.<Void>testConsumer())
          .assertFailure(CompositeException.class);
  
          List<Throwable> errors = TestHelper.compositeList(to.errors().get(0));
  
          for (int i = 0; i < 10; i++) {
              TestHelper.assertError(errors, i, TestException.class);
          }
      }
  
      @Test
      public void normalNonDelayErrorOuter() {
          Observable.range(1, 10).concatWith(Observable.<Integer>error(new TestException()))
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          }, false)
          .test()
          .assertFailure(TestException.class);
      }
  
      @Test
      public void fused() {
          TestObserverEx<Integer> to = new TestObserverEx<>(QueueFuseable.ANY);
  
          Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          })
          .<Integer>toObservable()
          .subscribe(to);
  
          to
          .assertFuseable()
          .assertFusionMode(QueueFuseable.ASYNC)
          .assertResult();
      }
  
      @Test
      public void disposed() {
          TestHelper.checkDisposed(Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          }));
      }
  
      @Test
      public void innerObserver() {
          Observable.range(1, 3)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return new Completable() {
                      @Override
                      protected void subscribeActual(CompletableObserver observer) {
                          observer.onSubscribe(Disposable.empty());
  
                          assertFalse(((Disposable)observer).isDisposed());
  
                          ((Disposable)observer).dispose();
  
                          assertTrue(((Disposable)observer).isDisposed());
                      }
                  };
              }
          })
          .test();
      }
  
      @Test
      public void badSource() {
          TestHelper.checkBadSourceObservable(new Function<Observable<Integer>, Object>() {
              @Override
              public Object apply(Observable<Integer> o) throws Exception {
                  return o.flatMapCompletable(new Function<Integer, CompletableSource>() {
                      @Override
                      public CompletableSource apply(Integer v) throws Exception {
                          return Completable.complete();
                      }
                  });
              }
          }, false, 1, null);
      }
  
      @Test
      public void fusedInternalsObservable() {
          Observable.range(1, 10)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return Completable.complete();
              }
          })
          .toObservable()
          .subscribe(new Observer<Object>() {
              @Override
              public void onSubscribe(Disposable d) {
                  QueueDisposable<?> qd = (QueueDisposable<?>)d;
                  try {
                      assertNull(qd.poll());
                  } catch (Throwable ex) {
                      throw new RuntimeException(ex);
                  }
                  assertTrue(qd.isEmpty());
                  qd.clear();
              }
  
              @Override
              public void onNext(Object t) {
              }
  
              @Override
              public void onError(Throwable t) {
              }
  
              @Override
              public void onComplete() {
              }
          });
      }
  
      @Test
      public void innerObserverObservable() {
          Observable.range(1, 3)
          .flatMapCompletable(new Function<Integer, CompletableSource>() {
              @Override
              public CompletableSource apply(Integer v) throws Exception {
                  return new Completable() {
                      @Override
                      protected void subscribeActual(CompletableObserver observer) {
                          observer.onSubscribe(Disposable.empty());
  
                          assertFalse(((Disposable)observer).isDisposed());
  
                          ((Disposable)observer).dispose();
  
                          assertTrue(((Disposable)observer).isDisposed());
                      }
                  };
              }
          })
          .toObservable()
          .test();
      }
  
      @Test
      public void badSourceObservable() {
          TestHelper.checkBadSourceObservable(new Function<Observable<Integer>, Object>() {
              @Override
              public Object apply(Observable<Integer> o) throws Exception {
                  return o.flatMapCompletable(new Function<Integer, CompletableSource>() {
                      @Override
                      public CompletableSource apply(Integer v) throws Exception {
                          return Completable.complete();
                      }
                  }).toObservable();
              }
          }, false, 1, null);
      }
  
      @Test
      public void undeliverableUponCancel() {
          TestHelper.checkUndeliverableUponCancel(new ObservableConverter<Integer, Completable>() {
              @Override
              public Completable apply(Observable<Integer> upstream) {
                  return upstream.flatMapCompletable(new Function<Integer, Completable>() {
                      @Override
                      public Completable apply(Integer v) throws Throwable {
                          return Completable.complete().hide();
                      }
                  });
              }
          });
      }
  
      @Test
      public void undeliverableUponCancelDelayError() {
          TestHelper.checkUndeliverableUponCancel(new ObservableConverter<Integer, Completable>() {
              @Override
              public Completable apply(Observable<Integer> upstream) {
                  return upstream.flatMapCompletable(new Function<Integer, Completable>() {
                      @Override
                      public Completable apply(Integer v) throws Throwable {
                          return Completable.complete().hide();
                      }
                  }, true);
              }
          });
      }
  
      @Test
      public void doubleOnSubscribe() {
          TestHelper.checkDoubleOnSubscribeObservable(o -> o.flatMapCompletable(v -> Completable.never()).toObservable());
      }
  
      @Test
      public void doubleOnSubscribeCompletable() {
          TestHelper.checkDoubleOnSubscribeObservableToCompletable(o -> o.flatMapCompletable(v -> Completable.never()));
      }
  
      @Test
      public void cancelWhileMapping() throws Throwable {
          for (int i = 0; i < TestHelper.RACE_DEFAULT_LOOPS; i++) {
              PublishSubject<Integer> ps1 = PublishSubject.create();
  
              TestObserver<Object> to = new TestObserver<>();
              CountDownLatch cdl = new CountDownLatch(1);
  
              ps1.flatMapCompletable(v -> {
                  TestHelper.raceOther(() -> {
                      to.dispose();
                  }, cdl);
                  return Completable.complete();
              })
              .toObservable()
              .subscribe(to);
  
              ps1.onNext(1);
  
              cdl.await();
          }
      }
  
      @Test
      public void cancelWhileMappingCompletable() throws Throwable {
          for (int i = 0; i < TestHelper.RACE_DEFAULT_LOOPS; i++) {
              PublishSubject<Integer> ps1 = PublishSubject.create();
  
              TestObserver<Void> to = new TestObserver<>();
              CountDownLatch cdl = new CountDownLatch(1);
  
              ps1.flatMapCompletable(v -> {
                  TestHelper.raceOther(() -> {
                      to.dispose();
                  }, cdl);
                  return Completable.complete();
              })
              .subscribe(to);
  
              ps1.onNext(1);
  
              cdl.await();
          }
      }
  }
  