docs: private IQueryResult<T> filteredResult(IQueryResult<T> unfilteredResult) {
          List<T> unfilteredList = unfilteredResult.getResults();
          List<T> filteredList = unfilteredList == null ? null : filters.filter(unfilteredList);
          Map<String, Object> metadata = Collections.<String, Object> singletonMap("unfiltered", unfilteredResult);
          return QueryUtil.packageResult(filteredList, unfilteredResult.getStatus(), metadata);
      }