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.schedulers;
  
  import io.reactivex.rxjava3.core.Completable;
  import io.reactivex.rxjava3.core.Flowable;
  import io.reactivex.rxjava3.core.RxJavaTest;
  import io.reactivex.rxjava3.schedulers.Schedulers;
  import org.junit.Test;
  
  import java.util.concurrent.TimeUnit;
  
  public class IoScheduledReleaseTest extends RxJavaTest {
  
      /* This test will be stuck in a deadlock if IoScheduler.USE_SCHEDULED_RELEASE is not set */
      @Test
      public void scheduledRelease() {
          boolean savedScheduledRelease = IoScheduler.USE_SCHEDULED_RELEASE;
          IoScheduler.USE_SCHEDULED_RELEASE = true;
          try {
              Flowable.just("item")
                      .observeOn(Schedulers.io())
                      .firstOrError()
                      .map(item -> {
                          for (int i = 0; i < 50; i++) {
                              Completable.complete()
                                      .observeOn(Schedulers.io())
                                      .blockingAwait();
                          }
                          return "Done";
                      })
                      .ignoreElement()
                      .test()
                      .awaitDone(5, TimeUnit.SECONDS)
                      .assertComplete();
          } finally {
              IoScheduler.USE_SCHEDULED_RELEASE = savedScheduledRelease;
          }
      }
  }
  