def message(self):

        return safe_unicode(self._commit.message)

    @LazyProperty

    def committer(self):

        return safe_unicode(getattr(self._commit, self._committer_property))

    @LazyProperty

    def author(self):

        return safe_unicode(getattr(self._commit, self._author_property))

    @LazyProperty

    def date(self):

        return date_fromtimestamp(getattr(self._commit, self._date_property),

                                  getattr(self._commit, self._date_tz_property))

    @LazyProperty

    def _timestamp(self):

        return getattr(self._commit, self._date_property)

    @LazyProperty

    def status(self):

        """

        Returns modified, added, removed, deleted files for current changeset

        """

        return self.changed, self.added, self.removed

    @LazyProperty

    def tags(self):

        _tags = []

        for tname, tsha in self.repository.tags.iteritems():

            if tsha == self.raw_id:

                _tags.append(tname)

        return _tags

    @LazyProperty

    def branch(self):

        # Note: This function will return one branch name for the changeset -

        # that might not make sense in Git where branches() is a better match

        # for the basic model

        heads = self.repository._heads(reverse=False)

        ref = heads.get(self._commit.id)

        if ref:

            return safe_unicode(ref)

    @LazyProperty

    def branches(self):

        heads = self.repository._heads(reverse=True)

    def _fix_path(self, path):

        """

        Paths are stored without trailing slash so we need to get rid off it if

        needed.

        """

        if path.endswith('/'):

            path = path.rstrip('/')

        return path

    def _get_id_for_path(self, path):

        path = safe_str(path)

        # FIXME: Please, spare a couple of minutes and make those codes cleaner;

        if path not in self._paths:

            path = path.strip('/')

            # set root tree

            tree = self.repository._repo[self._tree_id]

            if path == '':

                self._paths[''] = tree.id

                return tree.id

            splitted = path.split('/')

            dirs, name = splitted[:-1], splitted[-1]

            curdir = ''

            # initially extract things from root dir

            for item, stat, id in tree.iteritems():

                if curdir:

                    name = '/'.join((curdir, item))

                else:

                    name = item

                self._paths[name] = id

                self._stat_modes[name] = stat

            for dir in dirs:

                if curdir:

                    curdir = '/'.join((curdir, dir))

                else:

                    curdir = dir

                dir_id = None

                for item, stat, id in tree.iteritems():

                    if dir == item:

                        dir_id = id

                if dir_id:

                    # Update tree

                    tree = self.repository._repo[dir_id]

                    if not isinstance(tree, objects.Tree):

                        raise ChangesetError('%s is not a directory' % curdir)

                else:

        assert isinstance(cmd, list), cmd

        cmd = [settings.GIT_EXECUTABLE_PATH, '-c', 'core.quotepath=false'] + cmd

        try:

            p = subprocessio.SubprocessIOChunker(cmd, cwd=cwd, env=gitenv, shell=False)

        except (EnvironmentError, OSError) as err:

            # output from the failing process is in str(EnvironmentError)

            msg = ("Couldn't run git command %s.\n"

                   "Subprocess failed with '%s': %s\n" %

                   (cmd, type(err).__name__, err)

            ).strip()

            log.error(msg)

            raise RepositoryError(msg)

        try:

            stdout = b''.join(p.output)

            stderr = b''.join(p.error)

        finally:

            p.close()

        # TODO: introduce option to make commands fail if they have any stderr output?

        if stderr:

            log.debug('stderr from %s:\n%s', cmd, stderr)

        else:

            log.debug('stderr from %s: None', cmd)

        return stdout, stderr

    def run_git_command(self, cmd):

        """

        Runs given ``cmd`` as git command with cwd set to current repo.

        Returns stdout as unicode str ... or raise RepositoryError.

        """

        cwd = None

        if os.path.isdir(self.path):

            cwd = self.path

        stdout, _stderr = self._run_git_command(cmd, cwd=cwd)

        return safe_unicode(stdout)

    @classmethod

    def _check_url(cls, url):

        """

        Function will check given url and try to verify if it's a valid

        link. Sometimes it may happened that git will issue basic

        auth request that can cause whole API to hang when used from python

        or other external calls.

        On failures it'll raise urllib2.HTTPError, exception is also thrown

        when the return code is non 200

        """

        # check first if it's not an local url

        if os.path.isdir(url) or url.startswith('file:'):

            return True

        if url.startswith('git://'):

            return True

        if '+' in url[:url.find('://')]:

            url = url[url.find('+') + 1:]

        handlers = []

        url_obj = mercurial.util.url(url)

        test_uri, authinfo = url_obj.authinfo()

        if not test_uri.endswith('info/refs'):

            test_uri = test_uri.rstrip('/') + '/info/refs'

        url_obj.passwd = b'*****'

        cleaned_uri = str(url_obj)

        if authinfo:

            # create a password manager

            passmgr = urllib2.HTTPPasswordMgrWithDefaultRealm()

            passmgr.add_password(*authinfo)

            handlers.extend((mercurial.url.httpbasicauthhandler(passmgr),

                             mercurial.url.httpdigestauthhandler(passmgr)))

        o = urllib2.build_opener(*handlers)

        o.addheaders = [('User-Agent', 'git/1.7.8.0')]  # fake some git

        try:

            resp = o.open(req)

            if resp.code != 200:

                raise Exception('Return Code is not 200')

        except Exception as e:

            # means it cannot be cloned

            raise urllib2.URLError("[%s] org_exc: %s" % (cleaned_uri, e))

        # now detect if it's proper git repo

        gitdata = resp.read()

        if 'service=git-upload-pack' not in gitdata:

            raise urllib2.URLError(

                "url [%s] does not look like an git" % cleaned_uri)

        return True

    def _get_repo(self, create, src_url=None, update_after_clone=False,

                  bare=False):

        if create and os.path.exists(self.path):

            raise RepositoryError("Location already exist")

        if src_url and not create:

            raise RepositoryError("Create should be set to True if src_url is "

                                  "given (clone operation creates repository)")

        try:

            if create and src_url:

                GitRepository._check_url(src_url)

                self.clone(src_url, update_after_clone, bare)

                return Repo(self.path)

            elif create:

                os.makedirs(self.path)

                if bare:

                    return Repo.init_bare(self.path)

                else:

                    return Repo.init(self.path)

            else:

                return Repo(self.path)

        except (NotGitRepository, OSError) as err:

            raise RepositoryError(err)

    def _get_all_revisions(self):

        # we must check if this repo is not empty, since later command

        # fails if it is. And it's cheaper to ask than throw the subprocess

        # errors

        try:

            self._repo.head()

        except KeyError:

            return []

        rev_filter = settings.GIT_REV_FILTER

        cmd = ['rev-list', rev_filter, '--reverse', '--date-order']

        try:

            so = self.run_git_command(cmd)

        except RepositoryError:

            # Can be raised for empty repositories

            return []

        return so.splitlines()

    def _get_all_revisions2(self):

        # alternate implementation using dulwich

        return [c.commit.id for c in self._repo.get_walker(include=includes)]

    def _get_revision(self, revision):

        """

        Given any revision identifier, returns a 40 char string with revision hash.

        """

        if self._empty:

            raise EmptyRepositoryError("There are no changesets yet")

        if revision in (None, '', 'tip', 'HEAD', 'head', -1):

            revision = -1

        if isinstance(revision, int):

            try:

                return self.revisions[revision]

            except IndexError:

                msg = ("Revision %s does not exist for %s" % (revision, self))

                raise ChangesetDoesNotExistError(msg)

        if isinstance(revision, (str, unicode)):

            if revision.isdigit() and (len(revision) < 12 or len(revision) == revision.count('0')):

                try:

                    return self.revisions[int(revision)]

                except IndexError:

                    msg = "Revision %r does not exist for %s" % (revision, self)

                    raise ChangesetDoesNotExistError(msg)

            # get by branch/tag name

            _ref_revision = self._parsed_refs.get(revision)

            if _ref_revision:  # and _ref_revision[1] in [b'H', b'RH', b'T']:

                return ascii_str(_ref_revision[0])

            if revision in self.revisions:

                return revision

            # maybe it's a tag ? we don't have them in self.revisions

            if revision in self.tags.values():

                return revision

            if SHA_PATTERN.match(revision):

                msg = ("Revision %s does not exist for %s" % (revision, self))

                raise ChangesetDoesNotExistError(msg)

        raise ChangesetDoesNotExistError("Given revision %r not recognized" % revision)

    def get_ref_revision(self, ref_type, ref_name):

        """

        Returns ``GitChangeset`` object representing repository's

    def get_hook_location(self):

        """

        returns absolute path to location where hooks are stored

        """

        loc = os.path.join(self.path, 'hooks')

        if not self.bare:

            loc = os.path.join(self.path, '.git', 'hooks')

        return loc

    @LazyProperty

    def name(self):

        return os.path.basename(self.path)

    @LazyProperty

    def last_change(self):

        """

        Returns last change made on this repository as datetime object

        """

        return date_fromtimestamp(self._get_mtime(), makedate()[1])

    def _get_mtime(self):

        try:

            return time.mktime(self.get_changeset().date.timetuple())

        except RepositoryError:

            idx_loc = '' if self.bare else '.git'

            # fallback to filesystem

            in_path = os.path.join(self.path, idx_loc, "index")

            he_path = os.path.join(self.path, idx_loc, "HEAD")

            if os.path.exists(in_path):

                return os.stat(in_path).st_mtime

            else:

                return os.stat(he_path).st_mtime

    @LazyProperty

    def description(self):

        return safe_unicode(self._repo.get_description() or b'unknown')

    @LazyProperty

    def contact(self):

        undefined_contact = u'Unknown'

        return undefined_contact

    @property

    def branches(self):

        if not self.revisions:

            return {}

        sortkey = lambda ctx: ctx[0]

        return OrderedDict(sorted(_branches, key=sortkey, reverse=False))

    @LazyProperty

    def closed_branches(self):

        return {}

    @LazyProperty

    def tags(self):

        return self._get_tags()

    def _get_tags(self):

        if not self.revisions:

            return {}

        sortkey = lambda ctx: ctx[0]

        return OrderedDict(sorted(_tags, key=sortkey, reverse=True))

    def tag(self, name, user, revision=None, message=None, date=None,

            **kwargs):

        """

        Creates and returns a tag for the given ``revision``.

        :param name: name for new tag

        :param user: full username, i.e.: "Joe Doe <joe.doe@example.com>"

        :param revision: changeset id for which new tag would be created

        :param message: message of the tag's commit

        :param date: date of tag's commit

        :raises TagAlreadyExistError: if tag with same name already exists

        """

        if name in self.tags:

            raise TagAlreadyExistError("Tag %s already exists" % name)

        changeset = self.get_changeset(revision)

        message = message or "Added tag %s for commit %s" % (name,

            changeset.raw_id)

        self._repo.refs[b"refs/tags/%s" % name] = changeset._commit.id

        self._parsed_refs = self._get_parsed_refs()

        self.tags = self._get_tags()

        return changeset

    def remove_tag(self, name, user, message=None, date=None):

        """

        Removes tag with the given ``name``.

        :param name: name of the tag to be removed

        :param user: full username, i.e.: "Joe Doe <joe.doe@example.com>"

        :param message: message of the tag's removal commit

        :param date: date of tag's removal commit

        :raises TagDoesNotExistError: if tag with given name does not exists

        """

        if name not in self.tags:

            raise TagDoesNotExistError("Tag %s does not exist" % name)

        # self._repo.refs is a DiskRefsContainer, and .path gives the full absolute path of '.git'

        tagpath = os.path.join(self._repo.refs.path, 'refs', 'tags', name)

        try:

            os.remove(tagpath)

            self._parsed_refs = self._get_parsed_refs()

            self.tags = self._get_tags()

        except OSError as e:

            raise RepositoryError(e.strerror)

        return {}

    @LazyProperty

    def _parsed_refs(self):

        return self._get_parsed_refs()

    def _get_parsed_refs(self):

        """Return refs as a dict, like:

        { b'v0.2.0': [b'599ba911aa24d2981225f3966eb659dfae9e9f30', b'T'] }

        """

        _repo = self._repo

        refs = _repo.get_refs()

        keys = [(b'refs/heads/', b'H'),

                (b'refs/remotes/origin/', b'RH'),

                (b'refs/tags/', b'T')]

        _refs = {}

        for ref, sha in refs.iteritems():

            for k, type_ in keys:

                if ref.startswith(k):

                    _key = ref[len(k):]

                    if type_ == b'T':

                        obj = _repo.get_object(sha)

                        if isinstance(obj, Tag):

                            sha = _repo.get_object(sha).object[1]

                    _refs[_key] = [sha, type_]

                    break

        return _refs

    def _heads(self, reverse=False):

        refs = self._repo.get_refs()

        heads = {}

        for key, val in refs.items():

            for ref_key in [b'refs/heads/', b'refs/remotes/origin/']:

                if key.startswith(ref_key):

                    n = key[len(ref_key):]

                    if n not in [b'HEAD']:

                        heads[n] = val

        return heads if reverse else dict((y, x) for x, y in heads.iteritems())

    def get_changeset(self, revision=None):

        """

        Returns ``GitChangeset`` object representing commit from git repository

        at the given revision or head (most recent commit) if None given.

        """

        if isinstance(revision, GitChangeset):

            return revision

    def get_changesets(self, start=None, end=None, start_date=None,

           end_date=None, branch_name=None, reverse=False, max_revisions=None):

        """

        Returns iterator of ``GitChangeset`` objects from start to end (both

        are inclusive), in ascending date order (unless ``reverse`` is set).

        :param start: changeset ID, as str; first returned changeset

        :param end: changeset ID, as str; last returned changeset

        :param start_date: if specified, changesets with commit date less than

          ``start_date`` would be filtered out from returned set

        :param end_date: if specified, changesets with commit date greater than

          ``end_date`` would be filtered out from returned set

        :param branch_name: if specified, changesets not reachable from given

          branch would be filtered out from returned set

        :param reverse: if ``True``, returned generator would be reversed

          (meaning that returned changesets would have descending date order)

        :raise BranchDoesNotExistError: If given ``branch_name`` does not

            exist.

        :raise ChangesetDoesNotExistError: If changeset for given ``start`` or

          ``end`` could not be found.

        """

        if branch_name and branch_name not in self.branches:

            raise BranchDoesNotExistError("Branch '%s' not found"

                                          % branch_name)

        # actually we should check now if it's not an empty repo to not spaw

        # subprocess commands

        if self._empty:

            raise EmptyRepositoryError("There are no changesets yet")

        # %H at format means (full) commit hash, initial hashes are retrieved

        # in ascending date order

        cmd = ['log', '--date-order', '--reverse', '--pretty=format:%H']

        if max_revisions:

            cmd += ['--max-count=%s' % max_revisions]

        if start_date:

            cmd += ['--since', start_date.strftime('%m/%d/%y %H:%M:%S')]

        if end_date:

            cmd += ['--until', end_date.strftime('%m/%d/%y %H:%M:%S')]

        if branch_name:

            cmd.append(branch_name)

        else:

            cmd.append(settings.GIT_REV_FILTER)

        revs = self.run_git_command(cmd).splitlines()

        start_pos = 0

import mercurial.scmutil

import mercurial.sshpeer

import mercurial.tags

import mercurial.ui

import mercurial.url

import mercurial.util

from kallithea.lib.vcs.backends.base import BaseRepository, CollectionGenerator

from kallithea.lib.vcs.exceptions import (

    BranchDoesNotExistError, ChangesetDoesNotExistError, EmptyRepositoryError, RepositoryError, TagAlreadyExistError, TagDoesNotExistError, VCSError)

from kallithea.lib.vcs.utils import ascii_str, author_email, author_name, date_fromtimestamp, makedate, safe_bytes, safe_str, safe_unicode

from kallithea.lib.vcs.utils.lazy import LazyProperty

from kallithea.lib.vcs.utils.paths import abspath

from .changeset import MercurialChangeset

from .inmemory import MercurialInMemoryChangeset

from .workdir import MercurialWorkdir

log = logging.getLogger(__name__)

class MercurialRepository(BaseRepository):

    """

    Mercurial repository backend

    """

    DEFAULT_BRANCH_NAME = 'default'

    scm = 'hg'

    def __init__(self, repo_path, create=False, baseui=None, src_url=None,

                 update_after_clone=False):

        """

        Raises RepositoryError if repository could not be find at the given

        ``repo_path``.

        :param repo_path: local path of the repository

        :param create=False: if set to True, would try to create repository if

           it does not exist rather than raising exception

        :param baseui=None: user data

        :param src_url=None: would try to clone repository from given location

        :param update_after_clone=False: sets update of working copy after

          making a clone

        """

        if not isinstance(repo_path, str):

            raise VCSError('Mercurial backend requires repository path to '

                           'be instance of <str> got %s instead' %

                           type(repo_path))

        self.path = abspath(repo_path)

        self.baseui = baseui or mercurial.ui.ui()

        # We've set path and ui, now we can set _repo itself

        self._repo = self._get_repo(create, src_url, update_after_clone)

    @property

    def _empty(self):

        """

        Checks if repository is empty ie. without any changesets

        """

        # TODO: Following raises errors when using InMemoryChangeset...

        # return len(self._repo.changelog) == 0

        return len(self.revisions) == 0

    @LazyProperty

    def revisions(self):

        """

        Returns list of revisions' ids, in ascending order.  Being lazy

        attribute allows external tools to inject shas from cache.

        """

        return self._get_all_revisions()

    @LazyProperty

    def name(self):

        return os.path.basename(self.path)

    @LazyProperty

    def branches(self):

        return self._get_branches()

    @LazyProperty

    def closed_branches(self):

        return self._get_branches(normal=False, closed=True)

    @LazyProperty

    def allbranches(self):

        """

        List all branches, including closed branches.

        """

        return self._get_branches(closed=True)

    def _get_branches(self, normal=True, closed=False):

        """

        Gets branches for this repository

        Returns only not closed branches by default

        :param closed: return also closed branches for mercurial

        :param normal: return also normal branches

                          opts=mercurial.mdiff.diffopts(git=True,

                                        showfunc=True,

                                        ignorews=ignore_whitespace,

                                        context=context)))

    @classmethod

    def _check_url(cls, url, repoui=None):

        """

        Function will check given url and try to verify if it's a valid

        link. Sometimes it may happened that mercurial will issue basic

        auth request that can cause whole API to hang when used from python

        or other external calls.

        On failures it'll raise urllib2.HTTPError, exception is also thrown

        when the return code is non 200

        """

        # check first if it's not an local url

        if os.path.isdir(url) or url.startswith(b'file:'):

            return True

        if url.startswith(b'ssh:'):

            # in case of invalid uri or authentication issues, sshpeer will

            # throw an exception.

            mercurial.sshpeer.instance(repoui or mercurial.ui.ui(), url, False).lookup(b'tip')

            return True

        url_prefix = None

        if b'+' in url[:url.find(b'://')]:

            url_prefix, url = url.split(b'+', 1)

        handlers = []

        url_obj = mercurial.util.url(url)

        test_uri, authinfo = url_obj.authinfo()

        url_obj.passwd = b'*****'

        cleaned_uri = str(url_obj)

        if authinfo:

            # create a password manager

            passmgr = urllib2.HTTPPasswordMgrWithDefaultRealm()

            passmgr.add_password(*authinfo)

            handlers.extend((mercurial.url.httpbasicauthhandler(passmgr),

                             mercurial.url.httpdigestauthhandler(passmgr)))

        o = urllib2.build_opener(*handlers)

        o.addheaders = [('Content-Type', 'application/mercurial-0.1'),

                        ('Accept', 'application/mercurial-0.1')]

        try:

            resp = o.open(req)

            if resp.code != 200:

                raise Exception('Return Code is not 200')

        except Exception as e:

            # means it cannot be cloned

            raise urllib2.URLError("[%s] org_exc: %s" % (cleaned_uri, e))

        if not url_prefix: # skip svn+http://... (and git+... too)

            # now check if it's a proper hg repo

            try:

                mercurial.httppeer.instance(repoui or mercurial.ui.ui(), url, False).lookup(b'tip')

            except Exception as e:

                raise urllib2.URLError(

                    "url [%s] does not look like an hg repo org_exc: %s"

                    % (cleaned_uri, e))

        return True

    def _get_repo(self, create, src_url=None, update_after_clone=False):

        """

        Function will check for mercurial repository in given path and return

        a localrepo object. If there is no repository in that path it will

        raise an exception unless ``create`` parameter is set to True - in

        that case repository would be created and returned.

        If ``src_url`` is given, would try to clone repository from the

        location at given clone_point. Additionally it'll make update to

        working copy accordingly to ``update_after_clone`` flag

        """

        try:

            if src_url:

                url = safe_bytes(self._get_url(src_url))

                opts = {}

                if not update_after_clone:

                    opts.update({'noupdate': True})

                MercurialRepository._check_url(url, self.baseui)

                mercurial.commands.clone(self.baseui, url, self.path, **opts)

                # Don't try to create if we've already cloned repo

                create = False

            return mercurial.localrepo.instance(self.baseui, self.path, create=create)

        except (mercurial.error.Abort, mercurial.error.RepoError) as err:

            if create:

                msg = "Cannot create repository at %s. Original error was %s" \

                    % (self.path, err)

            else:

                msg = "Not valid repository at %s. Original error was %s" \

                    % (self.path, err)

            raise RepositoryError(msg)

    @LazyProperty

    def in_memory_changeset(self):

        return MercurialInMemoryChangeset(self)

    @LazyProperty

    def description(self):

        _desc = self._repo.ui.config(b'web', b'description', None, untrusted=True)

        return safe_unicode(_desc or b'unknown')

    @LazyProperty

    def contact(self):

        return safe_unicode(mercurial.hgweb.common.get_contact(self._repo.ui.config)

                            or b'Unknown')

    @LazyProperty

    def last_change(self):

        """

        Returns last change made on this repository as datetime object

        """

        return date_fromtimestamp(self._get_mtime(), makedate()[1])

    def _get_mtime(self):

        try:

            return time.mktime(self.get_changeset().date.timetuple())

        except RepositoryError:

            # fallback to filesystem

            cl_path = os.path.join(self.path, '.hg', "00changelog.i")

        rev_spec = "%%s & %s(%%s)" % _revset_predicates[ref_type]

        try:

            revs = self._repo.revs(rev_spec, ref_name, ref_name)

        except LookupError:

            msg = ("Ambiguous identifier %s:%s for %s" % (ref_type, ref_name, self.name))

            raise ChangesetDoesNotExistError(msg)

        except mercurial.error.RepoLookupError:

            msg = ("Revision %s:%s does not exist for %s" % (ref_type, ref_name, self.name))

            raise ChangesetDoesNotExistError(msg)

        if revs:

            revision = revs.last()

        else:

            # TODO: just report 'not found'?

            revision = ref_name

        return self._get_revision(revision)

    def _get_archives(self, archive_name='tip'):

        allowed = self.baseui.configlist(b"web", b"allow_archive",

                                         untrusted=True)

        for name, ext in [(b'zip', '.zip'), (b'gz', '.tar.gz'), (b'bz2', '.tar.bz2')]:

            if name in allowed or self._repo.ui.configbool(b"web",

                                                           b"allow" + name,

                                                           untrusted=True):

                yield {"type": name, "extension": ext, "node": archive_name}

    def _get_url(self, url):

        """

        Returns normalized url. If schema is not given, would fall

        to filesystem

        (``file:///``) schema.

        """

        url = safe_str(url)

        if url != 'default' and '://' not in url:

            url = "file:" + urllib.pathname2url(url)

        return url

    def get_hook_location(self):

        """

        returns absolute path to location where hooks are stored

        """

        return os.path.join(self.path, '.hg', '.hgrc')

    def get_changeset(self, revision=None):

        """

        Returns ``MercurialChangeset`` object representing repository's

        changeset at the given ``revision``.

        """

    def get_changesets(self, start=None, end=None, start_date=None,

                       end_date=None, branch_name=None, reverse=False, max_revisions=None):

        """

        Returns iterator of ``MercurialChangeset`` objects from start to end

        (both are inclusive)

        :param start: None, str, int or mercurial lookup format

        :param end:  None, str, int or mercurial lookup format

        :param start_date:

        :param end_date:

        :param branch_name:

        :param reversed: return changesets in reversed order

        """

        start_raw_id = self._get_revision(start)

        start_pos = None if start is None else self.revisions.index(start_raw_id)

        end_raw_id = self._get_revision(end)

        end_pos = None if end is None else self.revisions.index(end_raw_id)

        if start_pos is not None and end_pos is not None and start_pos > end_pos:

            raise RepositoryError("Start revision '%s' cannot be "

                                  "after end revision '%s'" % (start, end))

        if branch_name and branch_name not in self.allbranches:

            msg = ("Branch %s not found in %s" % (branch_name, self))

            raise BranchDoesNotExistError(msg)

        if end_pos is not None:

            end_pos += 1

        # filter branches

        filter_ = []

        if branch_name:

            filter_.append(b'branch("%s")' % safe_bytes(branch_name))

        if start_date:

            filter_.append(b'date(">%s")' % start_date)

        if end_date:

            filter_.append(b'date("<%s")' % end_date)

        if filter_ or max_revisions:

            if filter_:

                revspec = b' and '.join(filter_)

            else:

                revspec = b'all()'

            if max_revisions:

                revspec = b'limit(%s, %d)' % (revspec, max_revisions)

            revisions = mercurial.scmutil.revrange(self._repo, [revspec])

        else:

            revisions = self.revisions

        # this is very much a hack to turn this into a list; a better solution