anchor.diff:      UserInfo3 = #{uid => UserId3},
       CredState = <<"some_cred">>,
       Cred = <<"secret">>,
  -    MeckModules = [tts_data_sqlite, tts_cred_sup, tts_cred_worker],
  +    MeckModules = [tts_data_sqlite, tts_cred_sup, tts_cred_worker, tts_service],
       Token = #{},
       Params = [],
       MyPid = self(),
  -    AddFun = fun(User, Service, State) ->
  +    Interface = <<"test interface">>,
  +    AddFun = fun(User, Service, IFace, State) ->
  +                     IFace = Interface,
                        User = UserId1,
                        Service = ServiceId,
                        State = CredState,
  
positive.code:     UserInfo3 = #{uid => UserId3},
      UserInfo4 = #{uid => UserId4},
      CredState = <<"some_cred">>,
      Cred = <<"secret">>,
      MeckModules = [tts_data_sqlite, tts_cred_sup, tts_cred_worker],
      MyPid = self(),
      GetFun = fun(UserId) ->
                       case UserId of
                           UserId1 -> {ok, [{ServiceId, CredState}]};
                           UserId2 -> {ok, [{ServiceId, CredState}]};
                           UserId3 -> {ok, [{ServiceId, CredState}]};
                           _ -> {ok, []}
                       end
               end,
      DelFun = fun(UserId, Service, State) ->
                       Service = ServiceId,
                       State = CredState,
                       case UserId of
                           UserId1 -> ok;
                           UserId2 -> ok;
  
negative.code:     ok = meck:expect(tts_cred_worker, revoke, RevokeFun),
  
      {ok, Pid} = tts_credential:start_link(),
      {ok, RevokeResult, []} = tts_credential:revoke(CredId1, UserInfo1),
      {error, {script, <<>>}, []} = tts_credential:revoke(CredId2, UserInfo2),
      {error, {internal, just_because}, []} = tts_credential:revoke(CredId3, UserInfo3),
      {error, not_found, []} =  tts_credential:revoke(CredId4, UserInfo4),
      {error, bad_user, []} = tts_credential:revoke(CredId5, UserInfo4),
      ok = tts_credential:stop(),
      ok = test_util:wait_for_process_to_die(Pid,100),
      ok = test_util:meck_done(MeckModules),
  