Predicates.isNull(),
                    Predicates.notNull(),
                    Predicates.in(Arrays.asList(1)))));
    assertEvalsToFalse(nasty);

    Predicate<? super Integer> stillNasty = SerializableTester.reserializeAndAssert(nasty);

    assertEvalsToFalse(stillNasty);
  }

  // enum singleton pattern
  private enum TrimStringFunction implements Function<String, String> {
    INSTANCE;