this.trailers = builder.trailers
    this.body = builder.body
    this.socketHandler = builder.socketHandler
    this.webSocketListener = builder.webSocketListener
    this.inTunnel = builder.inTunnel
    this.informationalResponses = builder.informationalResponses
    this.throttleBytesPerPeriod = builder.throttleBytesPerPeriod
    this.throttlePeriodNanos = builder.throttlePeriodNanos

    server.enqueue(
      MockResponse
        .Builder()
        .inTunnel()
        .code(407)
        .addHeader("Proxy-Authenticate: Basic realm=\"localhost\"")
        .addHeader("Connection: close")
        .build(),
    )
    server.enqueue(
      MockResponse
        .Builder()
        .inTunnel()
        .build(),
    )
    server.enqueue(MockResponse())
    client =

     * calls should be attempted on the socket.
     */
    @Throws(IOException::class, InterruptedException::class)
    private fun processTunnelRequests(): Boolean {
      if (!dispatcher.peek().inTunnel) return true // No tunnel requests.

      val socket = MockWebServerSocket(raw)
      while (true) {
        val socketStillGood = processOneRequest(socket)

        server.enqueue(
          MockResponse
            .Builder()
            .code(407)
            .headers(headersOf("Proxy-Authenticate", "Basic realm=\"localhost\""))
            .inTunnel()
            .build(),
        )

        overrideBadImplementation(override = override.override, testItFails = testItFails)
      }

      OverrideParam.Authenticator -> {
        server.enqueue(

    This is only relevant for duplex request bodies, because they are written concurrently when
    reading the response body.

 *  New: `MockResponse.inTunnel()` is a new `mockwebserver3` API to configure responses that are
    served while creating a proxy tunnel. This obsoletes both the `tunnelProxy` argument on