split: close transaction in the unlikely event of a conflict while rebasing
`hg split` *should* never result in conflicts, but in case there are
bugs, we should at least commit the transaction so they can continue
the rebase. One of our users ran into the regression fixed by
D10120. They fixed the conflict and the tried to continue the rebase,
but it failed with "abort: cannot continue inconsistent rebase"
because the rebase state referred to commits written in a transaction
that was never committed.
Side note: `hg split` should probably turn off copy tracing to reduce
the impact of such bugs, and to speed it up as well. Copies made in
the rebased commits should still be respected because `hg rebase`
calls `copies.graftcopies()`.
Differential Revision: https://phab.mercurial-scm.org/D10164
# Copyright 2020 Joerg Sonnenberger <joerg@bec.de>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""reject_new_heads is a hook to check that branches touched by new changesets
have at most one open head. It can be used to enforce policies for
merge-before-push or rebase-before-push. It does not handle pre-existing
hydras.
Usage:
[hooks]
pretxnclose.reject_new_heads = \
python:hgext.hooklib.reject_new_heads.hook
"""
from __future__ import absolute_import
from mercurial.i18n import _
from mercurial import (
error,
pycompat,
)
def hook(ui, repo, hooktype, node=None, **kwargs):
if hooktype != b"pretxnclose":
raise error.Abort(
_(b'Unsupported hook type %r') % pycompat.bytestr(hooktype)
)
ctx = repo.unfiltered()[node]
branches = set()
for rev in repo.changelog.revs(start=ctx.rev()):
rev = repo[rev]
branches.add(rev.branch())
for branch in branches:
if len(repo.revs("head() and not closed() and branch(%s)", branch)) > 1:
raise error.Abort(
_(b'Changes on branch %r resulted in multiple heads')
% pycompat.bytestr(branch)
)