view hgext/hooklib/reject_new_heads.py @ 51925:3a90a6fd710d

dirstate: subclass the new dirstate Protocol class

Behold the chaos that ensues.  We'll use the generated *.pyi files to apply type
annotations to the interface, and see how much agrees with the documentation.

Since the CamelCase name was used to try to work around pytype issues with zope
interfaces and is a new innovation this cycle (see c1d7ac70980b), drop the
CamelCase name.  I think the Protocol classes *should* be CamelCase, but that
can be done later in one pass.  For now, the CamelCase alias is extra noise in
the *.pyi files.

# 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_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 annotations

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)
            )