list.add(THROWING_RUNNABLE, directExecutor());
    list.execute();
    list.add(THROWING_RUNNABLE, directExecutor());
  }

  public void testNulls() {
    new NullPointerTester().testAllPublicInstanceMethods(new ExecutionList());
  }

  private static final Runnable THROWING_RUNNABLE =
      () -> {
        throw new RuntimeException();
      };

    list.add(THROWING_RUNNABLE, directExecutor());
    list.execute();
    list.add(THROWING_RUNNABLE, directExecutor());
  }

  public void testNulls() {
    new NullPointerTester().testAllPublicInstanceMethods(new ExecutionList());
  }

  private static final Runnable THROWING_RUNNABLE =
      () -> {
        throw new RuntimeException();
      };

    return concat(strongImplementations(), weakImplementations());
  }

  public void testNull() throws Exception {
    for (Striped<?> striped : allImplementations()) {
      new NullPointerTester().testAllPublicInstanceMethods(striped);
    }
  }

  public void testSizes() {
    // not bothering testing all variations, since we know they share implementations
    assertThat(Striped.lock(100).size()).isAtLeast(100);

    return concat(strongImplementations(), weakImplementations());
  }

  public void testNull() throws Exception {
    for (Striped<?> striped : allImplementations()) {
      new NullPointerTester().testAllPublicInstanceMethods(striped);
    }
  }

  public void testSizes() {
    // not bothering testing all variations, since we know they share implementations
    assertThat(Striped.lock(100).size()).isAtLeast(100);

  }

  public void testNulls() {
    monitor.enter(); // Inhibit IllegalMonitorStateException
    new NullPointerTester()
        .setDefault(Monitor.Guard.class, new TestGuard(true))
        .testAllPublicInstanceMethods(monitor);
  }

  // TODO: Test enter(long, TimeUnit).
  // TODO: Test enterWhen(Guard, long, TimeUnit).
  // TODO: Test enterIf(Guard, long, TimeUnit).
  // TODO: Test waitFor(Guard, long, TimeUnit).

  }

  @J2ktIncompatible
  @GwtIncompatible // reflection
  public void testNulls() {
    new NullPointerTester().testAllPublicStaticMethods(EnumHashBiMap.class);
    new NullPointerTester().testAllPublicInstanceMethods(EnumHashBiMap.create(Currency.class));
  }

  }

  public void testNulls() {
    monitor.enter(); // Inhibit IllegalMonitorStateException
    new NullPointerTester()
        .setDefault(Monitor.Guard.class, new TestGuard(true))
        .testAllPublicInstanceMethods(monitor);
  }

  // TODO: Test enter(long, TimeUnit).
  // TODO: Test enterWhen(Guard, long, TimeUnit).
  // TODO: Test enterIf(Guard, long, TimeUnit).
  // TODO: Test waitFor(Guard, long, TimeUnit).

  }

  @J2ktIncompatible
  @GwtIncompatible // reflection
  public void testNulls() {
    new NullPointerTester().testAllPublicStaticMethods(EnumHashBiMap.class);
    new NullPointerTester().testAllPublicInstanceMethods(EnumHashBiMap.create(Currency.class));
  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNullPointerInstance() {
    table = create("foo", 1, 'a', "bar", 1, 'b', "foo", 2, 'c', "bar", 3, 'd');
    new NullPointerTester().testAllPublicInstanceMethods(table);
  }

                .testForwarding(String.class, Functions.<String>identity()));
  }

  public void testNulls() {
    new NullPointerTester()
        .setDefault(Class.class, Runnable.class)
        .testAllPublicInstanceMethods(new ForwardingWrapperTester());
  }

  private <T> void assertFailure(
      Class<T> interfaceType,
      Function<T, ? extends T> wrapperFunction,
      String... expectedMessages) {
    try {