*
   * <p>This is particularly useful in Java 8+ in combination with {@code Comparator.comparing},
   * e.g. {@code Comparator.comparing(Foo::hasBar, trueFirst())}.
   *
   * @since 21.0
   */
  public static Comparator<Boolean> trueFirst() {
    return BooleanComparator.TRUE_FIRST;
  }

  /**
   * Returns a {@code Comparator<Boolean>} that sorts {@code false} before {@code true}.
   *

  }

  public void testTrueFirst() {
    assertThat(Booleans.trueFirst().compare(true, true)).isEqualTo(0);
    assertThat(Booleans.trueFirst().compare(false, false)).isEqualTo(0);
    assertThat(Booleans.trueFirst().compare(true, false)).isLessThan(0);
    assertThat(Booleans.trueFirst().compare(false, true)).isGreaterThan(0);
  }

  public void testFalseFirst() {