anchor.diff:      {ok, #document{} = ParentDoc} = get(Parent),
       {ok, #document{value = #file_meta{name = FileName, version = V}} = FileDoc} = get(Entry),
       {ok, Scope} = get_scope(Parent),
  -    set_link_context(Scope),
       datastore:run_transaction(fun() ->
           ok = datastore:set_links(?LINK_STORE_LEVEL, ParentDoc, {FileName, FileDoc}),
           ok = datastore:set_links(?LINK_STORE_LEVEL, ParentDoc, {snapshot_name(FileName, V), FileDoc}),
  
positive.code:             {ok, #document{value = #file_meta{type = ?DIRECTORY_TYPE}}} ->
                  {ok, []};
              {ok, File} ->
                  set_link_context(File),
                  datastore:foreach_link(?LINK_STORE_LEVEL, File,
                      fun
                          (<<?LOCATION_PREFIX, _/binary>>, {_V, [{_, _, Key, file_location}]}, AccIn) ->
  
negative.code: get_ancestors(Entry) ->
      ?run(begin
          {ok, #document{key = Key} = Doc} = get(Entry),
          {ok, get_ancestors2(Key, [])}
      end).
  get_ancestors2(?ROOT_DIR_UUID, Acc) ->
  