merge: remove direct rustmod reference We shouldn't rely on this member being present in `dirstate.py`, this creates unnecessary coupling. This also can trigger certain issues in edge-cases where the policy is changed at runtime or multiple Python environments fight, which is an added bonus. Differential Revision: https://phab.mercurial-scm.org/D12217

from __future__ import absolute_import

from mercurial.i18n import _
from mercurial import changegroup, error, extensions


def abort(orig, *args, **kwargs):
    raise error.Abort(_('this is an exercise'))


def uisetup(ui):
    extensions.wrapfunction(changegroup, 'getbundler', abort)