view hgext/hooklib/reject_merge_commits.py @ 51711:832a1aeb576f

pytype: only try the hacky way of finding PYTHON if not provided

This allows us to work in more environments, like when using pyenv. This
syntax is compatible with all POSIX shells.

# Copyright 2020 Joerg Sonnenberger <[e-mail]>
#
# 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 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
            )