assertThat(Chars.contains(ARRAY234, (char) 1)).isFalse();
    assertThat(Chars.contains(new char[] {(char) -1}, (char) -1)).isTrue();
    assertThat(Chars.contains(ARRAY234, (char) 2)).isTrue();
    assertThat(Chars.contains(ARRAY234, (char) 3)).isTrue();
    assertThat(Chars.contains(ARRAY234, (char) 4)).isTrue();
  }

  public void testIndexOf() {
    assertThat(Chars.indexOf(EMPTY, (char) 1)).isEqualTo(-1);