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 java.util.concurrent.*;
  import java.util.concurrent.atomic.AtomicBoolean;
  
  import org.junit.Test;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.observers.TestObserver;
  import io.reactivex.rxjava3.schedulers.*;
  import io.reactivex.rxjava3.testsupport.TestHelper;
  
  public class ObservableToFutureTest extends RxJavaTest {
  
      @Test
      public void success() throws Exception {
          @SuppressWarnings("unchecked")
          Future<Object> future = mock(Future.class);
          Object value = new Object();
          when(future.get()).thenReturn(value);
  
          Observer<Object> o = TestHelper.mockObserver();
  
          TestObserver<Object> to = new TestObserver<>(o);
  
          Observable.fromFuture(future).subscribe(to);
  
          to.dispose();
  
          verify(o, times(1)).onNext(value);
          verify(o, times(1)).onComplete();
          verify(o, never()).onError(any(Throwable.class));
          verify(future, never()).cancel(true);
      }
  
      @Test
      public void successOperatesOnSuppliedScheduler() throws Exception {
          @SuppressWarnings("unchecked")
          Future<Object> future = mock(Future.class);
          Object value = new Object();
          when(future.get()).thenReturn(value);
  
          Observer<Object> o = TestHelper.mockObserver();
  
          TestScheduler scheduler = new TestScheduler();
          TestObserver<Object> to = new TestObserver<>(o);
  
          Observable.fromFuture(future).subscribeOn(scheduler).subscribe(to);
  
          verify(o, never()).onNext(value);
  
          scheduler.triggerActions();
  
          verify(o, times(1)).onNext(value);
      }
  
      @Test
      public void failure() throws Exception {
          @SuppressWarnings("unchecked")
          Future<Object> future = mock(Future.class);
          RuntimeException e = new RuntimeException();
          when(future.get()).thenThrow(e);
  
          Observer<Object> o = TestHelper.mockObserver();
  
          TestObserver<Object> to = new TestObserver<>(o);
  
          Observable.fromFuture(future).subscribe(to);
  
          to.dispose();
  
          verify(o, never()).onNext(null);
          verify(o, never()).onComplete();
          verify(o, times(1)).onError(e);
          verify(future, never()).cancel(true);
      }
  
      @Test
      public void cancelledBeforeSubscribe() throws Exception {
          @SuppressWarnings("unchecked")
          Future<Object> future = mock(Future.class);
          CancellationException e = new CancellationException("unit test synthetic cancellation");
          when(future.get()).thenThrow(e);
  
          Observer<Object> o = TestHelper.mockObserver();
  
          TestObserver<Object> to = new TestObserver<>(o);
          to.dispose();
  
          Observable.fromFuture(future).subscribe(to);
  
          to.assertNoErrors();
          to.assertNotComplete();
      }
  
      @Test
      public void cancellationDuringFutureGet() throws Exception {
          Future<Object> future = new Future<Object>() {
              private AtomicBoolean isCancelled = new AtomicBoolean(false);
              private AtomicBoolean isDone = new AtomicBoolean(false);
  
              @Override
              public boolean cancel(boolean mayInterruptIfRunning) {
                  isCancelled.compareAndSet(false, true);
                  return true;
              }
  
              @Override
              public boolean isCancelled() {
                  return isCancelled.get();
              }
  
              @Override
              public boolean isDone() {
                  return isCancelled() || isDone.get();
              }
  
              @Override
              public Object get() throws InterruptedException, ExecutionException {
                  Thread.sleep(500);
                  isDone.compareAndSet(false, true);
                  return "foo";
              }
  
              @Override
              public Object get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException {
                  return get();
              }
          };
  
          Observer<Object> o = TestHelper.mockObserver();
  
          TestObserver<Object> to = new TestObserver<>(o);
          Observable<Object> futureObservable = Observable.fromFuture(future);
  
          futureObservable.subscribeOn(Schedulers.computation()).subscribe(to);
  
          Thread.sleep(100);
  
          to.dispose();
  
          to.assertNoErrors();
          to.assertNoValues();
          to.assertNotComplete();
      }
  }
  