case <-m.ctx.Done():
				return
			case handlerIn <- in:
				m.send(message{Op: OpUnblockClMux, MuxID: m.ID, Flags: c.baseFlags})
			}
		}
	}
}

// sendResponses will send responses to the client.
func (m *muxServer) sendResponses(ctx context.Context, toSend <-chan []byte, c *Connection, handlerErr *atomic.Pointer[RemoteErr], outBlock <-chan struct{}) {
	for {
		// Process outgoing message.
		var payload []byte

    enableProtocol(Protocol.HTTP_2)
    val body =
      MockSocketHandler()
        .receiveRequest("request A\n")
        .sendResponse("response B\n")
        .receiveRequest("request C\n")
        .sendResponse("response D\n")
        .receiveRequest("request E\n")
        .sendResponse("response F\n")
        .exhaustRequest()
        .exhaustResponse()
    server.enqueue(
      MockResponse
        .Builder()

    val socketHandler =
      MockSocketHandler()
        .apply {
          receiveRequest("client says hello\n")
          sendResponse("server says hello\n")
          receiveRequest("client says goodbye\n")
          sendResponse("server says goodbye\n")
          exhaustResponse()
          exhaustRequest()
        }
    server.enqueue(socketHandler.upgradeResponse())

    client

        try {
          stream.source.exhausted()
          throw AssertionError("expected IOException")
        } catch (expected: IOException) {
        }
      }
    }

  @JvmOverloads
  fun sendResponse(
    s: String,
    responseSent: CountDownLatch = CountDownLatch(1),
  ) = apply {
    actions += { stream ->
      stream.sink.writeUtf8(s)
      stream.sink.flush()
      responseSent.countDown()
    }