anchor.diff:              case vmq_parser:parse(Data) of
                   {#mqtt_connack{}, Rest} ->
                       metrics({num_instances, {inc, 1}}),
  -                    Scenario = proplists:get_value(scenario, Opts, []),
  +                    Scenario = proplists:get_value(scenario, Opts1, []),
                       EScenario = enrich_scenario(Scenario, ClientId),
                       SetupSteps = proplists:get_value(setup, EScenario, []),
                       run_steps(Transport, Socket, SetupSteps),
  
positive.code: parse_rand_end([C|Rest], Acc) ->
      parse_rand_end(Rest, [C|Acc]).
  
  
  
  
  
  loop(Transport, Socket, Buf, Scenario) ->
      P = proto(Transport),
  
negative.code: 
  setup(Transport, Socket, Opts) ->
      ClientId = gen_client_id(),
      Opts1 = maybe_use_client_id_as_username(Opts, ClientId),
      Connect = vmq_parser:gen_connect(ClientId, Opts1),
      send(Transport, Socket, Connect, connect),
      {Proto, ProtoClosed, ProtoError} = proto(Transport),
      active_once(Transport, Socket),
  