content: /*
   * Copyright (C) 2016 The Android Open Source Project
   *
   * 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 androidx.test.internal.runner;
  
  import java.util.List;
  import org.junit.runner.Description;
  import org.junit.runner.Runner;
  import org.junit.runner.manipulation.Filter;
  import org.junit.runner.manipulation.Filterable;
  import org.junit.runner.manipulation.NoTestsRemainException;
  import org.junit.runner.manipulation.Sortable;
  import org.junit.runner.manipulation.Sorter;
  import org.junit.runner.notification.RunNotifier;
  
  /**
   * A {@link Runner} that does not actually run any tests but simply fires events for all leaf {@link
   * Description} instances in the {@link Description} returned by the wrapped {@link Runner}.
   */
  class NonExecutingRunner extends Runner implements Sortable, Filterable {
  
    private final Runner runner;
  
    NonExecutingRunner(Runner runner) {
      this.runner = runner;
    }
  
    @Override
    public Description getDescription() {
      return runner.getDescription();
    }
  
    @Override
    public void run(RunNotifier notifier) {
      generateListOfTests(notifier, getDescription());
    }
  
    @Override
    public void filter(Filter filter) throws NoTestsRemainException {
      filter.apply(runner);
    }
  
    @Override
    public void sort(Sorter sorter) {
      sorter.apply(runner);
    }
  
    /**
     * Generates a list of tests to run by recursing over the {@link Description} hierarchy and firing
     * events to simulate the tests being run successfully.
     *
     * @param runNotifier the notifier to which the events are sent.
     * @param description the description to traverse.
     */
    private void generateListOfTests(RunNotifier runNotifier, Description description) {
      List<Description> children = description.getChildren();
      if (children.isEmpty()) {
        runNotifier.fireTestStarted(description);
        runNotifier.fireTestFinished(description);
      } else {
        for (Description child : children) {
          generateListOfTests(runNotifier, child);
        }
      }
    }
  }
  