hgext/hooklib/reject_merge_commits.py
author Joerg Sonnenberger <joerg@bec.de>
Sat, 07 Sep 2019 14:50:39 +0200
changeset 44413 4cabeea6d214
child 48875 6000f5b25c9b
permissions -rw-r--r--
hgext: start building a library for simple hooks Many workflows depend on hooks to enforce certain policies, e.g. to prevent forced pushes. The Mercurial Guide includes some cases and Google can help finding others, but it can save users a lot of time if hg itself has a couple of examples for further customization. Differential Revision: https://phab.mercurial-scm.org/D6825

# 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_merge_commits is a hook to check new changesets for merge commits.
Merge commits are allowed only between different branches, i.e. merging
a feature branch into the main development branch. This can be used to
enforce policies for linear commit histories.

Usage:
  [hooks]
  pretxnchangegroup.reject_merge_commits = \
    python:hgext.hooklib.reject_merge_commits.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"pretxnchangegroup":
        raise error.Abort(
            _(b'Unsupported hook type %r') % pycompat.bytestr(hooktype)
        )

    ctx = repo.unfiltered()[node]
    for rev in repo.changelog.revs(start=ctx.rev()):
        rev = repo[rev]
        parents = rev.parents()
        if len(parents) < 2:
            continue
        if all(repo[p].branch() == rev.branch() for p in parents):
            raise error.Abort(
                _(
                    b'%s rejected as merge on the same branch. '
                    b'Please consider rebase.'
                )
                % rev
            )