anchor.diff:  
   %%--------------------------------------------------------------------
   %% @doc
  -%% Returns content of storage test file.
  -%% @end
  -%%--------------------------------------------------------------------
  --spec read_test_file(helpers:helper(), helpers:user_ctx(), helpers:file_id()) ->
  -    Content :: binary().
  -read_test_file(Helper, UserCtx, FileId) ->
  -    Handle = helpers:get_helper_handle(Helper, UserCtx),
  -    {ok, FileHandle} = helpers:open(Handle, FileId, read),
  -    {ok, Content} = helpers:read(FileHandle, 0, ?TEST_FILE_CONTENT_LEN),
  -    ok = helpers:release(FileHandle),
  -    Content.
  -
  -%%--------------------------------------------------------------------
  -%% @doc
  -%% Verifies content of storage test file.
  +%% Verifies content of storage test file and removes it.
   %% @end
   %%--------------------------------------------------------------------
   -spec verify_test_file(helpers:helper(), helpers:user_ctx(), helpers:file_id(),
  
positive.code:         <<Acc/binary, (rand:uniform(26) + 96)>>
      end, <<>>, lists:seq(1, Length)).
  
  -spec verify_storage_internal(helpers:helper(), helpers:user_ctx(), [node()],
      helpers:file_id(), Content :: binary()) ->
      {ok, {helpers:file_id(), binary()}} | {error, term()}.
  
negative.code: verify_test_file(Helper, UserCtx, FileId, ExpectedFileContent) ->
      case read_test_file(Helper, UserCtx, FileId) of
          ExpectedFileContent ->
              remove_test_file(Helper, UserCtx, FileId, byte_size(ExpectedFileContent)),
              ok;
          UnexpectedFileContent ->
              {error, {storage_test_file, {ExpectedFileContent, UnexpectedFileContent}}}
  