anchor.diff:  
       [ { "server pid alive", ?_assert( ProcAlive ) }
       , { "receive event", ?_assertEqual(
  -                            { ok, [ ?EVENT, "SomeEvent" ] },
  +                            [ ?EVENT, "SomeEvent" ],
                               ResEvent ) }
       , { "server stopped", ?_assertEqual( shutdown , ResStop ) }
       , { "server pid not alive", ?_assertNot( ProcAlive2 ) }
  
positive.code: %% ===================================================================
  %% Internal functions
  %% ===================================================================
  
  -spec start_driver( string() | binary(), [ string() | binary() ] ) ->
      { ok, port() } | { error, term() }.
  
negative.code:     case start_driver( Driver, Params ) of
          { ok, Port } ->
              Info = [ erlang:port_info( Port, os_pid ) ],
              send_owner( State, start, { ok, Info } ),
              { noreply, State#state{ port = Port } };
          Error ->
              send_owner( State, start, Error ),
              { stop, Error , State }
      end;
  
  