anchor.diff:  		 dbus_proxy:call(O, <<"net.lizenn.dbus.SampleInterface">>, <<"HelloWorld">>, [])),
       ok.    
   
  +call_method_err2(Config) ->
  +    {ok, O} = dbus_proxy:start_link(?config(bus, Config), ?SERVICE, <<"/root">>),
  +    ?assertMatch({error, {'org.freedesktop.DBus.UnknownMethod', _}},
  +		 dbus_proxy:call(O, <<"net.lizenn.dbus.SampleInterface">>, <<"bad_method">>, [])),
  +    ok.    
  +
  +call_method_err3(Config) ->
  +    {ok, O} = dbus_proxy:start_link(?config(bus, Config), ?SERVICE, <<"/root">>),
  +    ?assertMatch({error, {'org.freedesktop.DBus.UnknownInterface', _}},
  +		 dbus_proxy:call(O, <<"net.lizenn.dbus.BadInterface">>, <<"HelloWorld">>, [])),
  +    ok.    
  +
   
   %%%
   %%% Priv
  
positive.code: 	 connect_service/1,
  	 walk_node/1,
  	 call_method/1,
  	 call_method_err1/1
  	]).
  
  suite() ->
  
negative.code: 		   ,walk_node
  		   ,call_method
  		   ,call_method_err1
  		   ,call_method_err2
  		   ,call_method_err3
  		   ]}
      ].
  
  