~loggerhead-team/loggerhead/trunk-rich

#

# Copyright (C) 2008, 2009 Canonical Ltd.

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335  USA

#

"""Cache the whole history data needed by loggerhead about a branch."""

import logging

import time

from breezy.revision import NULL_REVISION, is_null

from breezy.tsort import merge_sort

def _strip_NULL_ghosts(revision_graph):

    """

    Copied over from breezy meant as a temporary workaround for

    deprecated methods.

    """

    # Filter ghosts, and null:

    if NULL_REVISION in revision_graph:

        del revision_graph[NULL_REVISION]

    for key, parents in revision_graph.items():

        revision_graph[key] = tuple(parent for parent in parents if parent

            in revision_graph)

    return revision_graph

def compute_whole_history_data(branch):

    """Compute _rev_info and _rev_indices for a branch.

    See History.__doc__ for what these data structures mean.

    """

    z = time.time()

    last_revid = branch.last_revision()

    log = logging.getLogger('loggerhead.%s' %

                            (branch.get_config().get_nickname(),))

    graph = branch.repository.get_graph()

    parent_map = dict((key, value) for key, value in

        graph.iter_ancestry([last_revid]) if value is not None)

    _revision_graph = _strip_NULL_ghosts(parent_map)

    _rev_info = []

    _rev_indices = {}

    if is_null(last_revid):

        _merge_sort = []

    else:

        _merge_sort = merge_sort(

            _revision_graph, last_revid, generate_revno=True)

    for info in _merge_sort:

        seq, revid, merge_depth, revno, end_of_merge = info

        revno_str = '.'.join(str(n) for n in revno)

        parents = _revision_graph[revid]

        _rev_indices[revid] = len(_rev_info)

        _rev_info.append([(seq, revid, merge_depth, revno_str, end_of_merge), (), parents])

    for revid in _revision_graph.keys():

        if _rev_info[_rev_indices[revid]][0][2] == 0:

            continue

        for parent in _revision_graph[revid]:

            c = _rev_info[_rev_indices[parent]]

            if revid not in c[1]:

                c[1] = c[1] + (revid,)

    log.info('built revision graph cache: %.3f secs' % (time.time() - z,))

    return (_rev_info, _rev_indices)