assertEquals("x-", Strings.padEnd("x", 2, '-'));
    assertEquals("x--", Strings.padEnd("x", 3, '-'));
    assertEquals("xx-", Strings.padEnd("xx", 3, '-'));
  }

  public void testPadEnd_negativeMinLength() {
    assertSame("x", Strings.padEnd("x", -1, '-'));
  }

  public void testPadEnd_null() {
    assertThrows(NullPointerException.class, () -> Strings.padEnd(null, 5, '0'));
  }