:param file_idx_writer: the whoosh index writer to add to

        :param repo_name: name of the repository we're indexing

        :param repo: instance of vcs repo

        """

        i_cnt = iwc_cnt = 0

        log.debug('building index for [%s]' % repo.path)

        for idx_path in self.get_paths(repo):

            i, iwc = self.add_doc(file_idx_writer, idx_path, repo, repo_name)

            i_cnt += i

            iwc_cnt += iwc

        log.debug('added %s files %s with content for repo %s' %

                  (i_cnt + iwc_cnt, iwc_cnt, repo.path))

        return i_cnt, iwc_cnt

    def update_changeset_index(self):

        idx = open_dir(self.index_location, indexname=CHGSET_IDX_NAME)

        with idx.searcher() as searcher:

            writer = idx.writer()

            writer_is_dirty = False

            try:

                indexed_total = 0

                for repo_name, repo in self.repo_paths.items():

                    # skip indexing if there aren't any revs in the repo

                    num_of_revs = len(repo)

                    if num_of_revs < 1:

                        continue

                    qp = QueryParser('repository', schema=CHGSETS_SCHEMA)

                    q = qp.parse(u"last:t AND %s" % repo_name)

                    results = searcher.search(q)

                    # default to scanning the entire repo

                    last_rev = 0

                    start_id = None

                    if len(results) > 0:

                        # assuming that there is only one result, if not this

                        # may require a full re-index.

                        start_id = results[0]['raw_id']

                        last_rev = repo.get_changeset(revision=start_id).revision

                    # there are new changesets to index or a new repo to index

                    if last_rev == 0 or num_of_revs > last_rev + 1:

                        # delete the docs in the index for the previous