*
 * Percent encoding replaces a character (like `\ud83c\udf69`) with its UTF-8 hex bytes (like
 * `%F0%9F%8D%A9`). This approach works for whitespace characters, control characters, non-ASCII
 * characters, and characters that already have another meaning in a particular context.
 *
 * Percent encoding is used in every URL component except for the hostname. But the set of

    val part = parts.nextPart()!!
    assertThat(part.headers).isEqualTo(headersOf())
    assertThat(part.body.readUtf8()).isEqualTo("abcd")

    assertThat(parts.nextPart()).isNull()
  }

  @Test fun `other characters after boundary`() {
    val multipart =
      """
      |--simple boundary hi
      """.trimMargin()
        .replace(Regex("(?m)simple boundary$"), "simple boundary ")
        .replace("\n", "\r\n")

    consistent with the length of the response body.

 *  Fix: Don't crash when converting a `HttpUrl` instance with an unresolvable hostname to a URI.
    The new behavior strips invalid characters like `"` and `{` from the hostname before converting.

 *  Fix: Undo a performance regression introduced in OkHttp 4.0 caused by differences in behavior

    assertThat(URLConnection.getDefaultRequestProperty("X-setDefaultRequestProperty")).isNull()
  }

  /**
   * Reads `count` characters from the stream. If the stream is exhausted before `count`
   * characters can be read, the remaining characters are returned and the stream is closed.
   */
  private fun readAscii(
    inputStream: InputStream,
    count: Int,
  ): String {

    buffer.writeUtf8(
      """
      |  0221
      |  0234-024F
      |  0000-001F; [CONTROL CHARACTERS]
      |  007F; DELETE
      |
      """.trimMargin(),
    )

    val rangeList = buffer.readCodePointSet()
    assertEquals(
      listOf(
        0x0221..0x0221,
        0x0234..0x024f,
        // [CONTROL CHARACTERS].
        0x0000..0x001f,
        // DELETE.
        0x007f..0x007f,
      ),

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

        // 'If a string contains any RandALCat character, a RandALCat character MUST be the last
        // character of the string.'
        if (validateBuffer.exhausted() && codePoint !in randalcatSet) return null
      } else {

            partCount++
            break@afterBoundaryLoop
          }

          1 -> {
            // "--": No more parts.
            if (whitespace) throw ProtocolException("unexpected characters after boundary")
            if (partCount == 0) throw ProtocolException("expected at least 1 part")
            noMoreParts = true
            return null
          }

          2, 3 -> {

}

/**
 * Returns the index of the first character in this string that is either a control character (like
 * `\u0000` or `\n`) or a non-ASCII character. Returns -1 if this string has no such characters.
 */
internal fun String.indexOfControlOrNonAscii(): Int {
  for (i in 0 until length) {
    val c = this[i]
    if (c <= '\u001f' || c >= '\u007f') {
      return i
    }
  }
  return -1
}

   E0001; LANGUAGE TAG

   2FF0-2FFB; [IDEOGRAPHIC DESCRIPTION CHARACTERS]...