# Copyright 2017 FUJIWARA Katsunori <foozy@lares.dti.ne.jp>

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

"""

Compatibility module

"""

from __future__ import absolute_import

from mercurial import (

    obsolete,

    scmutil,

    util,

)

getmarkers = None

successorssets = None

try:

    from mercurial import obsutil

    getmarkers = getattr(obsutil, 'getmarkers', None)

    successorssets = getattr(obsutil, 'successorssets', None)

except ImportError:

    pass

if getmarkers is None:

    getmarkers = obsolete.getmarkers

if successorssets is None:

    successorssets = obsolete.successorssets

def startpager(ui, cmd):

    """function to start a pager in case ui.pager() exists"""

    try:

        ui.pager(cmd)

    except AttributeError:

        pass

def cleanupnodes(repo, replacements, operation, moves=None):

    # create obsmarkers and move bookmarks

    # XXX we should be creating marker as we go instead of only at the end,

    # this makes the operations more modulars

    if util.safehasattr(scmutil, 'cleanupnodes'):

        scmutil.cleanupnodes(repo, replacements, 'changetopics',

                             moves=moves)

    else:

        relations = [(repo[o], tuple(repo[n] for n in new))

                     for (o, new) in replacements.iteritems()]