anchor.diff:      stop_counter(CounterPid),
       %% then
       ?assertReceivedMatch(
  -        {counterOnComplete, {ok, RequestsNum}, {erros, 0}}, ?TIMEOUT).
  -
  -%% TODO...
  +        {counterOnComplete, {ok, RequestsNum}, {errors, 0}}, ?TIMEOUT).
  +
   many_requests_to_one_file(Config) ->
       %% test sending many requests to one file
       %% requested blocks of file are intersected
  
positive.code: generate_requests_to_one_file(RequestsNum, Worker1, Worker2, Chunk) ->
      [
          remote_apply(Worker1, rtransfer, prepare_request,
              [Worker2, ?TEST_FILE_UUID, I, Chunk / 2])
          || I <- lists:seq(0, RequestsNum - 2, 2)
      ].
  
  fetch_many(Refs, Worker1, Notify, OnComplete) ->
  
negative.code: 
      fetch_many(Refs, Worker1, notify_fun(), on_complete_fun(CounterPid)),
  
      stop_counter(CounterPid),
      %% then
      ?assertReceivedMatch(
          {counterOnComplete, {ok, RequestsNum}, {errors, 0}}, ?TIMEOUT).
  
  error_open_fun_test(Config) ->
      %% test with open_fun callback returning an error
  