anchor.diff:                       tester_parse_state:state(), integer(), test_options()) -> ok.
   run_test(Module, Func, Arity, Iterations, ParseState, Threads, Options) ->
       Master = self(),
  +    Dict = erlang:get(),
       _Pids = [spawn_link(
                  fun() ->
                          Name = list_to_atom("run_test:" ++ integer_to_list(Thread)),
                          catch(erlang:register(Name, self())),
  +                       %% copy the dictionary of the original tester process
  +                       %% to worker threads (allows to join a pid_group if
  +                       %% necessary for a test
  +                       [ erlang:put(K, V) || {K, V} <- Dict ],
                          Result = run(Module, Func, Arity,
                                       Iterations div Threads, ParseState, Options,
                                       Thread),
  
positive.code:                      false -> skipped
                   end,
  
            %% if a feeder is found, test with feeder and ignore the
            %% exclude list, as a feeder is expected to feed the
            %% tested fun appropriately (will type check feeder
            %% results for required input types anyhow).
            FeederFun = list_to_atom(atom_to_list(Fun) ++ "_feeder"),
            case lists:member({FeederFun, Arity}, FunList) of
                true ->
                    ct:pal("Testing with feeder ~p:~p/~p~n",
  
negative.code: %
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  -spec register_type_checker({typedef, module(), atom()}, module(), atom()) ->
                                     true.
  register_type_checker(Type, Module, Function) ->
      tester_global_state:register_type_checker(Type, Module, Function).
  
  -spec unregister_type_checker({typedef, module(), atom()}) -> true | ok.
  unregister_type_checker(Type) ->
      tester_global_state:unregister_type_checker(Type).
  
  -spec register_value_creator({typedef, module(), atom()}, module(), atom(), non_neg_integer()) -> true.
  register_value_creator(Type, Module, Function, Arity) ->
      tester_global_state:register_value_creator(Type, Module, Function, Arity).
  
  -spec unregister_value_creator({typedef, module(), atom()}) -> true | ok.
  unregister_value_creator(Type) ->
      tester_global_state:unregister_value_creator(Type).
  