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.observers;
  
  import static io.reactivex.rxjava3.internal.util.ExceptionHelper.timeoutMessage;
  import static org.junit.Assert.*;
  
  import java.util.*;
  import java.util.concurrent.*;
  
  import org.junit.*;
  
  import io.reactivex.rxjava3.core.RxJavaTest;
  import io.reactivex.rxjava3.disposables.Disposable;
  import io.reactivex.rxjava3.exceptions.TestException;
  import io.reactivex.rxjava3.internal.functions.Functions;
  import io.reactivex.rxjava3.plugins.RxJavaPlugins;
  import io.reactivex.rxjava3.schedulers.Schedulers;
  import io.reactivex.rxjava3.testsupport.TestHelper;
  
  public class FutureObserverTest extends RxJavaTest {
      FutureObserver<Integer> fo;
  
      @Before
      public void before() {
          fo = new FutureObserver<>();
      }
  
      @Test
      public void cancel2() {
  
          fo.dispose();
  
          assertFalse(fo.isCancelled());
          assertFalse(fo.isDisposed());
          assertFalse(fo.isDone());
  
          for (int i = 0; i < 2; i++) {
              fo.cancel(i == 0);
  
              assertTrue(fo.isCancelled());
              assertTrue(fo.isDisposed());
              assertTrue(fo.isDone());
          }
  
          List<Throwable> errors = TestHelper.trackPluginErrors();
          try {
              fo.onNext(1);
              fo.onError(new TestException("First"));
              fo.onError(new TestException("Second"));
              fo.onComplete();
  
              assertTrue(fo.isCancelled());
              assertTrue(fo.isDisposed());
              assertTrue(fo.isDone());
  
              TestHelper.assertUndeliverable(errors, 0, TestException.class);
              TestHelper.assertUndeliverable(errors, 1, TestException.class);
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void cancel() throws Exception {
          assertFalse(fo.isDone());
  
          assertFalse(fo.isCancelled());
  
          fo.cancel(false);
  
          assertTrue(fo.isDone());
  
          assertTrue(fo.isCancelled());
  
          try {
              fo.get();
              fail("Should have thrown");
          } catch (CancellationException ex) {
              // expected
          }
  
          try {
              fo.get(1, TimeUnit.MILLISECONDS);
              fail("Should have thrown");
          } catch (CancellationException ex) {
              // expected
          }
      }
  
      @Test
      public void onError() throws Exception {
          List<Throwable> errors = TestHelper.trackPluginErrors();
  
          try {
              fo.onError(new TestException("One"));
  
              fo.onError(new TestException("Two"));
  
              try {
                  fo.get(5, TimeUnit.MILLISECONDS);
              } catch (ExecutionException ex) {
                  assertTrue(ex.toString(), ex.getCause() instanceof TestException);
                  assertEquals("One", ex.getCause().getMessage());
              }
  
              TestHelper.assertUndeliverable(errors, 0, TestException.class, "Two");
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void onNext() throws Exception {
          fo.onNext(1);
          fo.onComplete();
  
          assertEquals(1, fo.get(5, TimeUnit.MILLISECONDS).intValue());
      }
  
      @Test
      public void onSubscribe() throws Exception {
          List<Throwable> errors = TestHelper.trackPluginErrors();
  
          try {
  
              Disposable d1 = Disposable.empty();
  
              fo.onSubscribe(d1);
  
              Disposable d2 = Disposable.empty();
  
              fo.onSubscribe(d2);
  
              assertFalse(d1.isDisposed());
              assertTrue(d2.isDisposed());
  
              TestHelper.assertError(errors, 0, IllegalStateException.class, "Disposable already set!");
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void cancelRace() {
          for (int i = 0; i < TestHelper.RACE_DEFAULT_LOOPS; i++) {
              final FutureObserver<Integer> fo = new FutureObserver<>();
  
              Runnable r = new Runnable() {
                  @Override
                  public void run() {
                      fo.cancel(false);
                  }
              };
  
              TestHelper.race(r, r);
          }
      }
  
      @Test
      public void await() throws Exception {
          Schedulers.single().scheduleDirect(new Runnable() {
              @Override
              public void run() {
                  fo.onNext(1);
                  fo.onComplete();
              }
          }, 100, TimeUnit.MILLISECONDS);
  
          assertEquals(1, fo.get(5, TimeUnit.SECONDS).intValue());
      }
  
      @Test
      public void onErrorCancelRace() {
          RxJavaPlugins.setErrorHandler(Functions.emptyConsumer());
          try {
              for (int i = 0; i < TestHelper.RACE_DEFAULT_LOOPS; i++) {
                  final FutureObserver<Integer> fo = new FutureObserver<>();
  
                  final TestException ex = new TestException();
  
                  Runnable r1 = new Runnable() {
                      @Override
                      public void run() {
                          fo.cancel(false);
                      }
                  };
  
                  Runnable r2 = new Runnable() {
                      @Override
                      public void run() {
                          fo.onError(ex);
                      }
                  };
  
                  TestHelper.race(r1, r2);
              }
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void onCompleteCancelRace() {
          RxJavaPlugins.setErrorHandler(Functions.emptyConsumer());
          try {
              for (int i = 0; i < TestHelper.RACE_DEFAULT_LOOPS; i++) {
                  final FutureObserver<Integer> fo = new FutureObserver<>();
  
                  if (i % 3 == 0) {
                      fo.onSubscribe(Disposable.empty());
                  }
  
                  if (i % 2 == 0) {
                      fo.onNext(1);
                  }
  
                  Runnable r1 = new Runnable() {
                      @Override
                      public void run() {
                          fo.cancel(false);
                      }
                  };
  
                  Runnable r2 = new Runnable() {
                      @Override
                      public void run() {
                          fo.onComplete();
                      }
                  };
  
                  TestHelper.race(r1, r2);
              }
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void onErrorOnComplete() throws Exception {
          List<Throwable> errors = TestHelper.trackPluginErrors();
          try {
              fo.onError(new TestException("One"));
              fo.onComplete();
  
              try {
                  fo.get(5, TimeUnit.MILLISECONDS);
              } catch (ExecutionException ex) {
                  assertTrue(ex.toString(), ex.getCause() instanceof TestException);
                  assertEquals("One", ex.getCause().getMessage());
              }
  
              TestHelper.assertUndeliverable(errors, 0, NoSuchElementException.class);
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void onCompleteOnError() throws Exception {
          List<Throwable> errors = TestHelper.trackPluginErrors();
          try {
              fo.onComplete();
              fo.onError(new TestException("One"));
  
              try {
                  assertNull(fo.get(5, TimeUnit.MILLISECONDS));
              } catch (ExecutionException ex) {
                  assertTrue(ex.toString(), ex.getCause() instanceof NoSuchElementException);
              }
  
              TestHelper.assertUndeliverable(errors, 0, TestException.class);
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void onNextCompleteOnError() throws Exception {
          List<Throwable> errors = TestHelper.trackPluginErrors();
          try {
              fo.onNext(1);
              fo.onComplete();
              fo.onError(new TestException("One"));
  
              assertEquals((Integer)1, fo.get(5, TimeUnit.MILLISECONDS));
  
              TestHelper.assertUndeliverable(errors, 0, TestException.class);
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void cancelOnError() throws Exception {
          List<Throwable> errors = TestHelper.trackPluginErrors();
          try {
              fo.cancel(true);
              fo.onError(new TestException("One"));
  
              try {
                  fo.get(5, TimeUnit.MILLISECONDS);
                  fail("Should have thrown");
              } catch (CancellationException ex) {
                  // expected
              }
              TestHelper.assertUndeliverable(errors, 0, TestException.class);
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void cancelOnComplete() throws Exception {
          List<Throwable> errors = TestHelper.trackPluginErrors();
          try {
              fo.cancel(true);
              fo.onComplete();
  
              try {
                  fo.get(5, TimeUnit.MILLISECONDS);
                  fail("Should have thrown");
              } catch (CancellationException ex) {
                  // expected
              }
  
              TestHelper.assertUndeliverable(errors, 0, NoSuchElementException.class);
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void onNextThenOnCompleteTwice() throws Exception {
          fo.onNext(1);
          fo.onComplete();
          fo.onComplete();
  
          assertEquals(1, fo.get(5, TimeUnit.MILLISECONDS).intValue());
      }
  
      @Test(expected = InterruptedException.class)
      public void getInterrupted() throws Exception {
          Thread.currentThread().interrupt();
          fo.get();
      }
  
      @Test
      public void completeAsync() throws Exception {
          Schedulers.single().scheduleDirect(new Runnable() {
              @Override
              public void run() {
                  fo.onNext(1);
                  fo.onComplete();
              }
          }, 500, TimeUnit.MILLISECONDS);
  
          assertEquals(1, fo.get().intValue());
      }
  
      @Test
      public void getTimedOut() throws Exception {
          try {
              fo.get(1, TimeUnit.NANOSECONDS);
              fail("Should have thrown");
          } catch (TimeoutException expected) {
              assertEquals(timeoutMessage(1, TimeUnit.NANOSECONDS), expected.getMessage());
          }
      }
  
      @Test
      public void cancelOnSubscribeRace() {
          for (int i = 0; i < TestHelper.RACE_DEFAULT_LOOPS; i++) {
              final FutureObserver<Integer> fo = new FutureObserver<>();
  
              Runnable r = new Runnable() {
                  @Override
                  public void run() {
                      fo.cancel(false);
                  }
              };
  
              Disposable d = Disposable.empty();
  
              TestHelper.race(r, () -> fo.onSubscribe(d));
          }
      }
  }
  