message: Add unidirectional test
diff: @@ -543,3 +543,19 @@ fn keep_alive_large_rtt() {
  assert!(delay > rtt);
  }
  }
  +
  +/// Only the recipient of a unidirectional stream can keep it alive.
  +#[test]
  +fn keep_alive_uni() {
  + let mut client = default_client();
  + let mut server = default_server();
  + connect(&mut client, &mut server);
  +
  + let stream = client.stream_create(StreamType::UniDi).unwrap();
  + client.stream_keep_alive(stream, true).unwrap_err();
  + let _ = client.stream_send(stream, DEFAULT_STREAM_DATA).unwrap();
  + let dgram = client.process_output(now()).dgram();
  +
  + server.process_input(dgram.unwrap(), now());
  + server.stream_keep_alive(stream, true).unwrap();
  +}
  