anchor.diff:      ComplementaryPermsPerFile, AllRequiredPerms, ExtraData, group
   ) ->
       OperationRequiresOwnership = lists:any(fun({_, Perm}) ->
  -        Perm == owner orelse Perm == owner_if_parent_sticky
  +        Perm == owner
       end, AllRequiredPerms),
   
       case OperationRequiresOwnership of
  
positive.code:     ls_test/1,
      readdir_plus_test/1,
      get_child_attr_test/1,
  
      create_file_test/1,
      open_for_read_test/1,
      open_for_write_test/1,
      open_for_rdwr_test/1,
      create_and_open_test/1,
  
      get_parent_test/1,
      get_file_path_test/1,
  
negative.code:             ParentDirPath = <<TestCaseRootDirPath/binary, "/dir1">>,
              ParentDirGuid = maps:get(ParentDirPath, ExtraData),
              lfm_proxy:create_and_open(W, SessId, ParentDirGuid, <<"file1">>, 8#777)
          end
      }, Config).
  
  
  truncate_test(Config) ->
      [W | _] = ?config(op_worker_nodes, Config),
  
      run_tests(W, #test_spec{
          root_dir = atom_to_binary(?FUNCTION_NAME, utf8),
          files = [#file{
              name = <<"file1">>,
              perms = [?write_object]
          }],
          operation = fun(_OwnerSessId, SessId, TestCaseRootDirPath, ExtraData) ->
              FilePath = <<TestCaseRootDirPath/binary, "/file1">>,
              FileGuid = maps:get(FilePath, ExtraData),
              lfm_proxy:truncate(W, SessId, {guid, FileGuid}, 0)
          end
      }, Config).
  
  
  rm_file_test(Config) ->
      [W | _] = ?config(op_worker_nodes, Config),
  
      run_tests(W, #test_spec{
          root_dir = atom_to_binary(?FUNCTION_NAME, utf8),
          files = [
              #dir{
                  name = <<"dir1">>,
                  perms = [?traverse_container, ?delete_object],
                  children = [
                      #file{
                          name = <<"file1">>,
                          perms = [?delete]
                      }
                  ]
              }
          ],
          operation = fun(_OwnerSessId, SessId, TestCaseRootDirPath, ExtraData) ->
              FilePath = <<TestCaseRootDirPath/binary, "/dir1/file1">>,
              FileGuid = maps:get(FilePath, ExtraData),
              lfm_proxy:unlink(W, SessId, {guid, FileGuid})
          end
      }, Config).
  
  