.addEqualityGroup(Predicates.not(Predicates.notNull()))
        .testEquals();
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testNot_serialization() {
    checkSerialization(Predicates.not(isOdd()));
  }

  /*
   * Tests for all the different flavors of Predicates.and().
   */

  public void testAnd_applyNoArgs() {

  public void testOf_last() {
    SortedSet<String> set = of("e", "f", "b", "d", "c");
    assertEquals("f", set.last());
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testOf_serialization() {
    SortedSet<String> set = of("e", "f", "b", "d", "c");
    SortedSet<String> copy = SerializableTester.reserializeAndAssert(set);
    assertTrue(elementsEqual(set, copy));