"Invalid URL host: \"[0:0:0:0:0:1:0.0.0.000001]\"",
    )
  }

  @Test
  fun hostIpv6WithIpv4SuffixWithHexadecimalPrefix() {
    // Chrome interprets a leading '0x' as hexadecimal; Firefox rejects them. (We reject them.)
    assertInvalid(
      "http://[0:0:0:0:0:1:0.0x10.0.0x10]/",
      "Invalid URL host: \"[0:0:0:0:0:1:0.0x10.0.0x10]\"",
    )
  }

  @Test

   *
   * ```
   *    180C; ; Map to nothing
   *    0041; 0061; Case map
   *    0390; 03B9 0308 0301; Case map
   * ```
   *
   * Each line maps from a single hexadecimal code point to zero or more hexadecimal code points.
   * Elements are delimited by semicolons with a comment at the end of the line.
   */
  fun readCodePointMapping(path: Path): MappingListCodePointMapping {