}
      bias = adapt(i - oldi, codePoints.size + 1, oldi == 0)
      val deltaN = i / (codePoints.size + 1)
      if (n > Int.MAX_VALUE - deltaN) return false // Prevent overflow.
      n += deltaN
      i %= (codePoints.size + 1)

      if (n > 0x10ffff) return false // Not a valid code point.

      codePoints.add(i, n)

      i++
    }

    for (codePoint in codePoints) {

) {
  /**
   * Returns true if the [codePoint] was applied successfully. Returns false if it was disallowed.
   */
  fun map(
    codePoint: Int,
    sink: BufferedSink,
  ): Boolean {
    val index =
      mappings.binarySearch {
        when {
          it.sourceCodePoint1 < codePoint -> -1
          it.sourceCodePoint0 > codePoint -> 1
          else -> 0
        }
      }

      val codePoint = validateBuffer.readUtf8CodePoint()
      if (codePoint in prohibitSet) return null

      if (first) {
        firstIsRandalcat = codePoint in randalcatSet
      } else if (firstIsRandalcat) {
        // 'If a string contains any RandALCat character, the string MUST NOT contain any LCat
        // character.'
        if (codePoint in lcatSet) return null

 */
fun String.escapeDataString(): String {
  return buildString {
    for (codePoint in this@escapeDataString.codePoints()) {
      when (codePoint) {
        in 0..0x20,
        '"'.code,
        '$'.code,
        '\\'.code,
        '·'.code,
        127,
        -> append(String.format("\\u%04x", codePoint))

        else -> appendCodePoint(codePoint)
      }
    }
  }

    codePointString: String,
    encoding: UrlComponentEncodingTester.Encoding,
    component: Component,
  ) {
    testToUrl(codePoint, encoding, component)
    testFromUrl(codePoint, encoding, component)
    testUri(codePoint, codePointString, encoding, component)
  }

  private fun testToUrl(
    codePoint: Int,
    encoding: UrlComponentEncodingTester.Encoding,
    component: Component,
  ) {

  val bufferA = Buffer().writeUtf8(host)
  val bufferB = Buffer()

  // 1. Map, from bufferA to bufferB.
  while (!bufferA.exhausted()) {
    val codePoint = bufferA.readUtf8CodePoint()
    if (!IDNA_MAPPING_TABLE.map(codePoint, bufferB)) return null
  }

  // 2. Normalize, from bufferB to bufferA.
  val normalized = normalizeNfc(bufferB.readUtf8())
  bufferA.writeUtf8(normalized)

          continue
        }
        testEncodeAndDecode(codePoint, codePointString, component)
        if (encoding == Encoding.SKIP) continue
        testParseOriginal(codePoint, codePointString, encoding, component)
        testParseAlreadyEncoded(codePoint, encoding, component)

        val platform = urlComponentEncodingTesterJvmPlatform(component)
        platform.test(codePoint, codePointString, encoding, component)
      }
    }

}

class MappingListCodePointMapping(
  val mappings: Map<Int, String>,
) : CodePointMapping {
  override fun get(codePoint: Int) = mappings[codePoint]
}

class RangeListCodePointSet(
  val ranges: List<IntRange>,
) : CodePointSet {
  override fun contains(codePoint: Int) = ranges.any { codePoint in it }

  charset: Charset? = null,
): String {
  var codePoint: Int
  var i = pos
  while (i < limit) {
    codePoint = codePointAt(i)
    if (codePoint < 0x20 ||
      codePoint == 0x7f ||
      codePoint >= 0x80 && !unicodeAllowed ||
      codePoint.toChar() in encodeSet ||
      codePoint == '%'.code &&
      (!alreadyEncoded || strict && !isPercentEncoded(i, limit)) ||
      codePoint == '+'.code && plusIsSpace
    ) {

  private fun String.map(): String {
    val buffer = Buffer()
    for (codePoint in codePoints()) {
      require(table.map(codePoint, buffer))
    }
    return buffer.readUtf8()
  }

  private fun String.mapExpectingErrors(): String {
    val buffer = Buffer()
    var errorCount = 0
    for (codePoint in codePoints()) {
      if (!table.map(codePoint, buffer)) errorCount++
    }
    assertThat(errorCount).isGreaterThan(0)