anchor.diff:  %% Executes multiple test configurations.
   %% @end
   %%--------------------------------------------------------------------
  --spec exec_perf_config(M :: atom(), F :: atom(), Inputs :: list(), Ext :: list(), ConfigName :: atom(), Repeats :: integer()) -> ok.
  +-spec exec_perf_config(M :: atom(), F :: atom(), Inputs :: list(), Ext :: list(), ConfigName :: term(), Repeats :: integer()) -> ok.
   exec_perf_config(M, F, Inputs, Ext, ConfigName, Repeats) ->
     [I1] = Inputs,  % get first arg (test config)
     [Values, OkNum, Errors] = exec_multiple_tests(M, F, [I1 ++ Ext], Repeats),
  
positive.code: %% Executes multiple test configurations.
  %% @end
  %%--------------------------------------------------------------------
  -spec exec_perf_config(M :: atom(), F :: atom(), Inputs :: list(), Ext :: list(), Repeats :: integer()) -> ok.
  exec_perf_config(M, F, Inputs, {Name, ExtList}, Repeats) ->
    exec_perf_config(M, F, Inputs, ExtList, Name, Repeats);
  exec_perf_config(M, F, Inputs, Ext, Repeats) ->
  
negative.code:   MJson2 = proplists:delete(M, MJson),
  
    ConfKey = case ConfigName of
      N when is_atom(N) -> N;
      _ -> list_to_atom("config" ++ integer_to_list(length(FJson)+1))
    end,
  
    Json3 = [
  