from dulwich.client import SubprocessGitClient

                gitrepo = Repo(org_repo.path)

                SubprocessGitClient(thin_packs=False).fetch(safe_str(other_repo.path), gitrepo)

                gitrepo_remote = Repo(other_repo.path)

                SubprocessGitClient(thin_packs=False).fetch(safe_str(org_repo.path), gitrepo_remote)

                revs = [

                    x.commit.id

                    for x in gitrepo_remote.get_walker(include=[other_rev],

                                                       exclude=[org_rev])

                ]

                other_changesets = [other_repo.get_changeset(rev) for rev in reversed(revs)]

                if other_changesets:

                    ancestors = [other_changesets[0].parents[0].raw_id]

                else:

                    # no changesets from other repo, ancestor is the other_rev

                    ancestors = [other_rev]

                gitrepo.close()

                gitrepo_remote.close()

            else:

                    ['log', '--reverse', '--pretty=format:%H',

                     '-s', '%s..%s' % (org_rev, other_rev)]

                )

                other_changesets = [org_repo.get_changeset(cs)

                              for cs in re.findall(r'[0-9a-fA-F]{40}', so)]

                    ['merge-base', org_rev, other_rev]

                )

                ancestors = [re.findall(r'[0-9a-fA-F]{40}', so)[0]]

            org_changesets = []

        else:

            raise Exception('Bad alias only git and hg is allowed')

        return other_changesets, org_changesets, ancestors

    @LoginRequired(allow_default_user=True)

    @HasRepoPermissionLevelDecorator('read')

    def index(self, repo_name):

        c.compare_home = True

        c.a_ref_name = c.cs_ref_name = None

        return render('compare/compare_diff.html')

    @LoginRequired(allow_default_user=True)

    @HasRepoPermissionLevelDecorator('read')

    def compare(self, repo_name, org_ref_type, org_ref_name, other_ref_type, other_ref_name):

        org_ref_name = org_ref_name.strip()

        other_ref_name = other_ref_name.strip()

        # If merge is True:

    rev_data = []

    for l in git_stdin_lines:

        old_rev, new_rev, ref = l.strip().split(' ')

        _ref_data = ref.split('/')

        if _ref_data[1] in ['tags', 'heads']:

            rev_data.append({'old_rev': old_rev,

                             'new_rev': new_rev,

                             'ref': ref,

                             'type': _ref_data[1],

                             'name': '/'.join(_ref_data[2:])})

    git_revs = []

    for push_ref in rev_data:

        _type = push_ref['type']

        if _type == 'heads':

            if push_ref['old_rev'] == EmptyChangeset().raw_id:

                # update the symbolic ref if we push new repo

                if scm_repo.is_empty():

                    scm_repo._repo.refs.set_symbolic_ref('HEAD',

                                        'refs/heads/%s' % push_ref['name'])

                # build exclude list without the ref

                cmd = ['for-each-ref', '--format=%(refname)', 'refs/heads/*']

                ref = push_ref['ref']

                heads = [head for head in stdout.splitlines() if head != ref]

                # now list the git revs while excluding from the list

                cmd = ['log', push_ref['new_rev'], '--reverse', '--pretty=format:%H']

                cmd.append('--not')

                cmd.extend(heads) # empty list is ok

                git_revs += stdout.splitlines()

            elif push_ref['new_rev'] == EmptyChangeset().raw_id:

                # delete branch case

                git_revs += ['delete_branch=>%s' % push_ref['name']]

            else:

                cmd = ['log', '%(old_rev)s..%(new_rev)s' % push_ref,

                       '--reverse', '--pretty=format:%H']

                git_revs += stdout.splitlines()

        elif _type == 'tags':

            git_revs += ['tag=>%s' % push_ref['name']]

    process_pushed_raw_ids(git_revs)

    return 0

# Almost exactly like Mercurial contrib/hg-ssh:

def rejectpush(ui, **kwargs):

    """Mercurial hook to be installed as pretxnopen and prepushkey for read-only repos"""

    ex = get_hook_environment()

    ui.warn((b"Push access to %r denied\n") % safe_str(ex.repository))

    return 1

    def _get_filectx(self, path):

        path = self._fix_path(path)

        if self._get_kind(path) != NodeKind.FILE:

            raise ChangesetError("File does not exist for revision %s at "

                " '%s'" % (self.raw_id, path))

        return path

    def _get_file_nodes(self):

        return chain(*(t[2] for t in self.walk()))

    @LazyProperty

    def parents(self):

        """

        Returns list of parents changesets.

        """

        return [self.repository.get_changeset(parent)

                for parent in self._commit.parents]

    @LazyProperty

    def children(self):

        """

        Returns list of children changesets.

        """

        rev_filter = settings.GIT_REV_FILTER

            ['rev-list', rev_filter, '--children']

        )

        return [

            self.repository.get_changeset(cs)

            for parts in (l.split(' ') for l in so.splitlines())

            if parts[0] == self.raw_id

            for cs in parts[1:]

        ]

    def next(self, branch=None):

        if branch and self.branch != branch:

            raise VCSError('Branch option used on changeset not belonging '

                           'to that branch')

        cs = self

        while True:

            try:

                next_ = cs.revision + 1

                next_rev = cs.repository.revisions[next_]

            except IndexError:

                raise ChangesetDoesNotExistError

            cs = cs.repository.get_changeset(next_rev)

            if not branch or branch == cs.branch:

        Returns last commit of the file at the given ``path``.

        """

        return self.get_file_history(path, limit=1)[0]

    def get_file_history(self, path, limit=None):

        """

        Returns history of file as reversed list of ``Changeset`` objects for

        which file at given ``path`` has been modified.

        TODO: This function now uses os underlying 'git' and 'grep' commands

        which is generally not good. Should be replaced with algorithm

        iterating commits.

        """

        self._get_filectx(path)

        cs_id = safe_str(self.id)

        f_path = safe_str(path)

        if limit is not None:

            cmd = ['log', '-n', str(safe_int(limit, 0)),

                   '--pretty=format:%H', '-s', cs_id, '--', f_path]

        else:

            cmd = ['log',

                   '--pretty=format:%H', '-s', cs_id, '--', f_path]

        ids = re.findall(r'[0-9a-fA-F]{40}', so)

        return [self.repository.get_changeset(sha) for sha in ids]

    def get_file_history_2(self, path):

        """

        Returns history of file as reversed list of ``Changeset`` objects for

        which file at given ``path`` has been modified.

        """

        self._get_filectx(path)

        from dulwich.walk import Walker

        include = [self.id]

        walker = Walker(self.repository._repo.object_store, include,

                        paths=[path], max_entries=1)

        return [self.repository.get_changeset(sha)

                for sha in (x.commit.id for x in walker)]

    def get_file_annotate(self, path):

        """

        Returns a generator of four element tuples with

            lineno, sha, changeset lazy loader and line

        TODO: This function now uses os underlying 'git' command which is

        generally not good. Should be replaced with algorithm iterating

        commits.

        """

        cmd = ['blame', '-l', '--root', '-r', self.id, '--', path]

        # -l     ==> outputs long shas (and we need all 40 characters)

        # --root ==> doesn't put '^' character for boundaries

        # -r sha ==> blames for the given revision

        for i, blame_line in enumerate(so.split('\n')[:-1]):

            ln_no = i + 1

            sha, line = re.split(r' ', blame_line, 1)

            yield (ln_no, sha, lambda: self.repository.get_changeset(sha), line)

    def fill_archive(self, stream=None, kind='tgz', prefix=None,

                     subrepos=False):

        """

        Fills up given stream.

        :param stream: file like object.

        :param kind: one of following: ``zip``, ``tgz`` or ``tbz2``.

            Default: ``tgz``.

        :param prefix: name of root directory in archive.

            Default is repository name and changeset's raw_id joined with dash

            (``repo-tip.<KIND>``).

        :param subrepos: include subrepos in this archive.

        :raise ImproperArchiveTypeError: If given kind is wrong.

        :raise VcsError: If given stream is None

        """

        allowed_kinds = settings.ARCHIVE_SPECS

        if kind not in allowed_kinds:

        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 = ''.join(p.output)

            stderr = ''.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.

        """

        cwd = None

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

            cwd = self.path

    @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 = []

                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:

        except RepositoryError:

            # Can be raised for empty repositories

            return []

        return so.splitlines()

    def _get_all_revisions2(self):

        # alternate implementation using dulwich

        includes = [x[1][0] for x in self._parsed_refs.iteritems()

                    if x[1][1] != 'T']

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

    def _get_revision(self, revision):

        """

        For git backend we always return integer here. This way we ensure

        that changeset's revision attribute would become integer.

        """

        is_null = lambda o: len(o) == revision.count('0')

        if self._empty:

            raise EmptyRepositoryError("There are no changesets yet")

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

            return self.revisions[-1]

        """

        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)

        start_pos = 0

        end_pos = len(revs)

        if start:

            _start = self._get_revision(start)

            try:

                start_pos = revs.index(_start)

            except ValueError:

                pass

        if end is not None:

            _end = self._get_revision(end)

            try:

                end_pos = revs.index(_end)

            except ValueError:

                pass

        if None not in [start, end] and start_pos > end_pos:

            raise RepositoryError('start cannot be after end')

        if end_pos is not None:

            end_pos += 1

        revs = revs[start_pos:end_pos]

        if reverse:

        url = self._get_url(url)

        cmd = ['clone', '-q']

        if bare:

            cmd.append('--bare')

        elif not update_after_clone:

            cmd.append('--no-checkout')

        cmd += ['--', url, self.path]

        # If error occurs run_git_command raises RepositoryError already

        self.run_git_command(cmd)

    def pull(self, url):

        """

        Tries to pull changes from external location.

        """

        url = self._get_url(url)

        cmd = ['pull', '--ff-only', url]

        # If error occurs run_git_command raises RepositoryError already

        self.run_git_command(cmd)

    def fetch(self, url):

        """

        Tries to pull changes from external location.

        """

        url = self._get_url(url)

        cmd = ['fetch', url, '--']

        for line in (x for x in so.splitlines()):

            sha, ref = line.split('\t')

            cmd.append('+%s:%s' % (ref, ref))

        self.run_git_command(cmd)

    def _update_server_info(self):

        """

        runs gits update-server-info command in this repo instance

        """

        from dulwich.server import update_server_info

        try:

            update_server_info(self._repo)

        except OSError as e:

            if e.errno not in [errno.ENOENT, errno.EROFS]:

                raise

            # Workaround for dulwich crashing on for example its own dulwich/tests/data/repos/simple_merge.git/info/refs.lock

            log.error('Ignoring %s running update-server-info: %s', type(e).__name__, e)

    @LazyProperty

    def workdir(self):

        """

        Returns ``Workdir`` instance for this repository.

        """