revlog: make _partialmatch fail fast on almost-hex inputs
Before this change, resolving a revision like [0123456789^] on
a large repo can take multiple seconds because:
- hg does not realize this is a revset, so it tries various things,
including _partialmatch(b"0123456789^")
- after the rust lookup fails, it falls back to pure hg
- pure hg takes all-but-last chars and converts them to binary,
which *succeeds*, so it does the expensive part.
# tiny extension to abort a transaction very late during test
#
# Copyright 2020 Pierre-Yves David <pierre-yves.david@octobus.net>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from mercurial import (
error,
)
def abort(fp):
raise error.Abort(b"This is a late abort")
def reposetup(ui, repo):
class LateAbortRepo(repo.__class__):
def transaction(self, *args, **kwargs):
tr = super(LateAbortRepo, self).transaction(*args, **kwargs)
tr.addfilegenerator(
b'late-abort',
[b'late-abort'],
abort,
order=9999999,
post_finalize=True,
)
return tr
repo.__class__ = LateAbortRepo