public void testPadStart_null() {
    try {
      Strings.padStart(null, 5, '0');
      fail();
    } catch (NullPointerException expected) {
    }
  }

  public void testPadEnd_noPadding() {
    assertSame("", Strings.padEnd("", 0, '-'));
    assertSame("x", Strings.padEnd("x", 0, '-'));
    assertSame("x", Strings.padEnd("x", 1, '-'));
    assertSame("xx", Strings.padEnd("xx", 0, '-'));