hgext/remotefilelog/shallowverifier.py

rust: translation of missingancestors

This is as direct as possible a translation of the ancestor.missingancestors
Python class in pure Rust. The goal for this changeset is to make it easy
to compare with the Python version.

We also add to Python tests the cases that helped us develop and debug
this implementation.

Some possible optimizations are marked along the way as TODO comments

Differential Revision: https://phab.mercurial-scm.org/D5416

# shallowverifier.py - shallow repository verifier
#
# Copyright 2015 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import

from mercurial.i18n import _
from mercurial import verify

class shallowverifier(verify.verifier):
    def _verifyfiles(self, filenodes, filelinkrevs):
        """Skips files verification since repo's not guaranteed to have them"""
        self.repo.ui.status(
            _("skipping filelog check since remotefilelog is used\n"))
        return 0, 0