anchor.diff:  
       file:write(File, [iolist_to_binary(mochijson2:encode(prepare_to_write(Json3)))]),
       file:close(File),
  -    ok.
  +    case Errors of
  +        [] -> ok;
  +        _ -> error
  +    end.
   
   %%--------------------------------------------------------------------
   %% @doc
  
positive.code: -author("Michal Wrzeszcz").
  
  -annotation('function').
  -include_lib("annotations/include/types.hrl").
  
  -export([around_advice/4]).
  
negative.code: %% @end
  %%--------------------------------------------------------------------
  -spec exec_perf_config(M :: atom(), F :: atom(), Inputs :: list(), Ext :: list(),
      ConfigName :: term(), Repeats :: integer()) -> ok | error.
  exec_perf_config(M, F, Inputs, Ext, ConfigName, Repeats) ->
      [I1] = Inputs,  % get first arg (test config)
      {ValuesSums, ValuesLists, OkNum, Errors} = exec_multiple_tests(M, F, [I1 ++ Ext], Repeats),
  