"Payload size must be less than or equal to 125",
      )
    }
  }

  @Test fun pongTooLongThrows() {
    assertFailsWith<IllegalArgumentException> {
      serverWriter.writePong((binaryData(1000)))
    }.also { expected ->
      assertThat(expected.message).isEqualTo(
        "Payload size must be less than or equal to 125",
      )
    }
  }

  @Test fun mixedCasePunycode() {
    testDecodeOnly(
      unicode = "ليهمابتكلموشعربي؟",
      punycode = "Xn--EgBpDaJ6Bu4bXfGeHfVwXn",
    )
  }

  /**
   * It's invalid to have a label longer than 63 characters. If that's requested, the encoder may
   * overflow and return null.
   */
  @Test fun overflowEncodingOversizedLabel() {
    val a1000 = "a".repeat(1000)
    val a1000MaxCodePoint = a1000 + "\udbff\udfff"

    .build();
client.newCall(newYorkTimesRequest).enqueue(new Callback() {
  ...
});
```

Running this race over home WiFi shows the Times (`0002`) completes just slightly sooner than the Post (`0001`):

```
0001 https://www.washingtonpost.com/
0001 0.000 callStart
0002 https://www.nytimes.com/
0002 0.000 callStart
0002 0.010 dnsStart
0001 0.013 dnsStart
0001 0.022 dnsEnd

   */
  fun cancel()

  /**
   * Carries an exchange. This is usually a connection, but it could also be a connect plan for
   * CONNECT tunnels. Note that CONNECT tunnels are significantly less capable than connections.
   */
  interface Carrier {
    val route: Route

    fun trackFailure(
      call: RealCall,
      e: IOException?,
    )

    fun noNewExchanges()

    fun cancel()
  }

 *
 *  * Application Layer Protocol Negotiation (ALPN) enables the HTTPS port (443) to be used to
 *    negotiate HTTP/2.
 *
 * Unfortunately, older HTTPS servers refuse to connect when such options are presented. Rather than
 * avoiding these options entirely, this class allows a connection to be attempted with modern
 * options and then retried without them should the attempt fail.
 *
 * ## Connection Reuse
 *

    if (tag < 31) {
      val byte0 = tagClass or constructedBit or tag.toInt()
      sink.writeByte(byte0)
    } else {
      val byte0 = tagClass or constructedBit or 0b0001_1111
      sink.writeByte(byte0)
      writeVariableLengthLong(tag)
    }

    // Write the length. This takes 1 byte if length is less than 128.
    val length = content.size
    if (length < 128) {

      println(response.body.string())
    }
  }

  companion object {
    /**
     * The imgur client ID for OkHttp recipes. If you're using imgur for anything other than running
     * these examples, please request your own client ID! https://api.imgur.com/oauth2
     */
    private const val IMGUR_CLIENT_ID = "9199fdef135c122"
    private val MEDIA_TYPE_PNG = "image/png".toMediaType()
  }

  /**
   * A trust manager for Android applications that customize the trust manager.
   *
   * This class exploits knowledge of Android implementation details. This class is potentially
   * much faster to initialize than [BasicTrustRootIndex] because it doesn't need to load and
   * index trusted CA certificates.
   */
  internal data class CustomTrustRootIndex(
    private val trustManager: X509TrustManager,

    opcode: Int,
    payload: ByteString,
  ) {
    if (writerClosed) throw IOException("closed")

    val length = payload.size
    require(length <= PAYLOAD_BYTE_MAX) {
      "Payload size must be less than or equal to $PAYLOAD_BYTE_MAX"
    }

    val b0 = B0_FLAG_FIN or opcode
    sinkBuffer.writeByte(b0)

    var b1 = length
    if (isClient) {
      b1 = b1 or B1_FLAG_MASK

   *
   * @param code Status code as defined by
   *     [Section 7.4 of RFC 6455](http://tools.ietf.org/html/rfc6455#section-7.4).
   * @param reason Reason for shutting down, no longer than 123 bytes of UTF-8 encoded data (**not** characters) or null.
   * @throws IllegalArgumentException if [code] is invalid or [reason] is too long.
   */
  fun close(
    code: Int,
    reason: String?,
  ): Boolean