tester.forAllPublicStaticMethods(BadNullsFactory.class).thatReturn(Object.class).testNulls();
    } catch (AssertionError expected) {
      return;
    }
    fail();
  }

  public void testNullsOnReturnValues_returnTypeFiltered() throws Exception {
    try {
      tester
          .forAllPublicStaticMethods(BadNullsFactory.class)
          .thatReturn(Iterable.class)
          .testNulls();

  public void testExecutors_nullCheck() throws Exception {
    new ClassSanityTester()
        .setDefault(RateLimiter.class, RateLimiter.create(1.0))
        .forAllPublicStaticMethods(MoreExecutors.class)
        .thatReturn(Executor.class)
        .testNulls();
  }

  private static class TestApplication extends Application {
    private final List<Thread> hooks = new ArrayList<>();

    @Override

  public void testExecutors_nullCheck() throws Exception {
    new ClassSanityTester()
        .setDefault(RateLimiter.class, RateLimiter.create(1.0))
        .forAllPublicStaticMethods(MoreExecutors.class)
        .thatReturn(Executor.class)
        .testNulls();
  }

  private static class TestApplication extends Application {
    private final List<Thread> hooks = new ArrayList<>();

    @Override

  @J2ktIncompatible
  @GwtIncompatible // reflection
  public void testIterables_nullCheck() throws Exception {
    new ClassSanityTester()
        .forAllPublicStaticMethods(Iterables.class)
        .thatReturn(Iterable.class)
        .testNulls();
  }

  private static void verifyMergeSorted(
      Iterable<Iterable<Integer>> iterables, Iterable<Integer> unsortedExpected) {