Function<Object, Boolean> alwaysFalse = Functions.forPredicate(Predicates.alwaysFalse());

    assertTrue(alwaysTrue.apply(0));
    assertFalse(alwaysFalse.apply(0));

    new EqualsTester()
        .addEqualityGroup(alwaysTrue, Functions.forPredicate(Predicates.alwaysTrue()))
        .addEqualityGroup(alwaysFalse)
        .addEqualityGroup(Functions.identity())
        .testEquals();

    Function<Object, Boolean> alwaysFalse = Functions.forPredicate(Predicates.alwaysFalse());

    assertTrue(alwaysTrue.apply(0));
    assertFalse(alwaysFalse.apply(0));

    new EqualsTester()
        .addEqualityGroup(alwaysTrue, Functions.forPredicate(Predicates.alwaysTrue()))
        .addEqualityGroup(alwaysFalse)
        .addEqualityGroup(Functions.identity())
        .testEquals();

        return "Predicates.alwaysTrue()";
      }
    },
    /**
     * @see Predicates#alwaysFalse()
     */
    ALWAYS_FALSE {
      @Override
      public boolean apply(@Nullable Object o) {
        return false;
      }

      @Override
      public String toString() {
        return "Predicates.alwaysFalse()";
      }
    },
    /**
     * @see Predicates#isNull()
     */
    IS_NULL {

        return "Predicates.alwaysTrue()";
      }
    },
    /**
     * @see Predicates#alwaysFalse()
     */
    ALWAYS_FALSE {
      @Override
      public boolean apply(@Nullable Object o) {
        return false;
      }

      @Override
      public String toString() {
        return "Predicates.alwaysFalse()";
      }
    },
    /**
     * @see Predicates#isNull()
     */
    IS_NULL {

        .addEqualityGroup(isOdd())
        .addEqualityGroup(Predicates.alwaysFalse())
        .testEquals();
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testAlwaysTrue_serialization() {
    checkSerialization(Predicates.alwaysTrue());
  }

  /*
   * Tests for Predicates.alwaysFalse().
   */

  public void testAlwaysFalse_apply() throws Exception {

    assertThat(find(iterator, Predicates.alwaysFalse(), "woot")).isEqualTo("woot");
    assertFalse(iterator.hasNext());
  }

  public void testFind_withDefault_notPresent_nullReturn() {
    Iterable<String> list = Lists.newArrayList("cool", "pants");
    Iterator<String> iterator = list.iterator();
    assertThat(find(iterator, Predicates.alwaysFalse(), null)).isNull();
    assertFalse(iterator.hasNext());
  }

    assertThat(find(iterator, Predicates.alwaysFalse(), "woot")).isEqualTo("woot");
    assertFalse(iterator.hasNext());
  }

  public void testFind_withDefault_notPresent_nullReturn() {
    Iterable<String> list = Lists.newArrayList("cool", "pants");
    Iterator<String> iterator = list.iterator();
    assertThat(find(iterator, Predicates.alwaysFalse(), null)).isNull();
    assertFalse(iterator.hasNext());
  }

    assertThat(find(list, equalTo("cool"), "woot")).isEqualTo("cool");
    assertThat(find(list, equalTo("pants"), "woot")).isEqualTo("pants");
    assertThat(find(list, Predicates.alwaysFalse(), "woot")).isEqualTo("woot");
    assertThat(find(list, Predicates.alwaysFalse(), null)).isNull();
    assertThat(find(list, Predicates.alwaysTrue(), "woot")).isEqualTo("cool");
    assertCanIterateAgain(list);
  }

  public void testTryFind() {

    assertThat(iterable.firstMatch(equalTo("cool"))).hasValue("cool");
    assertThat(iterable.firstMatch(equalTo("pants"))).hasValue("pants");
    assertThat(iterable.firstMatch(Predicates.alwaysFalse())).isAbsent();
    assertThat(iterable.firstMatch(Predicates.alwaysTrue())).hasValue("cool");
  }

  private static final class IntegerValueOfFunction implements Function<String, Integer> {
    @Override