// These have a combination of invalid length, unrecognized characters and wrong padding.
    assertFailsToDecode(base32(), "AB=C", "Unrecognized character: =");
    assertFailsToDecode(base32(), "A=BCDE", "Invalid input length 6");
    assertFailsToDecode(base32(), "?", "Invalid input length 1");
  }

  public void testBase32UpperCaseIsNoOp() {
    assertThat(base32().upperCase()).isSameInstanceAs(base32());
  }

    // These have a combination of invalid length, unrecognized characters and wrong padding.
    assertFailsToDecode(base32(), "AB=C", "Unrecognized character: =");
    assertFailsToDecode(base32(), "A=BCDE", "Invalid input length 6");
    assertFailsToDecode(base32(), "?", "Invalid input length 1");
  }

  public void testBase32UpperCaseIsNoOp() {
    assertThat(base32().upperCase()).isSameInstanceAs(base32());
  }