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.completable;
  
  import static org.junit.Assert.assertTrue;
  
  import java.util.List;
  import java.util.concurrent.TimeUnit;
  
  import org.junit.Test;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.functions.Function;
  import io.reactivex.rxjava3.observers.TestObserver;
  import io.reactivex.rxjava3.plugins.RxJavaPlugins;
  import io.reactivex.rxjava3.schedulers.*;
  import io.reactivex.rxjava3.subjects.PublishSubject;
  import io.reactivex.rxjava3.testsupport.TestHelper;
  
  public class CompletableSubscribeOnTest extends RxJavaTest {
  
      @Test
      public void normal() {
          List<Throwable> list = TestHelper.trackPluginErrors();
          try {
              TestScheduler scheduler = new TestScheduler();
  
              TestObserver<Void> to = Completable.complete()
              .subscribeOn(scheduler)
              .test();
  
              scheduler.advanceTimeBy(1, TimeUnit.SECONDS);
  
              to.assertResult();
  
              assertTrue(list.toString(), list.isEmpty());
          } finally {
              RxJavaPlugins.reset();
          }
      }
  
      @Test
      public void dispose() {
          TestHelper.checkDisposed(PublishSubject.create().ignoreElements().subscribeOn(new TestScheduler()));
      }
  
      @Test
      public void doubleOnSubscribe() {
          TestHelper.checkDoubleOnSubscribeCompletable(new Function<Completable, CompletableSource>() {
              @Override
              public CompletableSource apply(Completable c) throws Exception {
                  return c.subscribeOn(Schedulers.single());
              }
          });
      }
  }
  