anchor.diff:  
   % public api
   -export([get_renewal_counter/0, get_lease_list/0]).
  -
  --record(mock_state, {
  -          renewal_enabled      = ?required(mock_state, renewal_enabled     ) :: boolean(),
  -          renewal_counter      = ?required(mock_state, renewal_counter     ) :: non_neg_integer()
  -         }).
  -
  --type mock_state_t() :: #mock_state{}.
   
   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   % public API
  
positive.code: 
  -spec get_lease_list() -> lease_list:lease_list().
  get_lease_list() ->
      comm:send_local(get_mock_pid(), {get_lease_list, self()}),
      receive
          {get_lease_list_response, List} ->
               List
      end.
  
  
negative.code: get_mock_pid() ->
      pid_groups:find_a(?MODULE).
  
  -spec increment_renewal_counter() -> ok.
  increment_renewal_counter() ->
      erlang:put(erlang:get(renewal_counter) + 1).
  
  -spec intercept_message(comm:message(), dht_node_state:state()) ->
                  dht_node_state:state().
  intercept_message(Msg, State) ->
      Owner = erlang:get(owner),
      comm:send_local(Owner, {intercepted_message, Msg}),
      State.
  