view mercurial/rewriteutil.py @ 35983:f540b6448738

largefiles: register wire protocol commands with modern APIs

The wireproto.wireprotocommand decorator is the preferred mechanism for
registering wire protocol commands. In addition, wireproto.commands
is no longer a 2-tuple and use of that 2-tuple API should be considered
deprecated.

This commit ports largefiles to use wireproto.wireprotocommand()
and ports to the "commandentry" API.

As part of this, the definition of the "lheads" wire protocol
command is moved to the proper stanza.

We stop short of actually using wireprotocommand as a decorator
in order to minimize churn. We should ideally move wire protocol
commands to the registrar mechanism. But that's for another
changeset.

Differential Revision: https://phab.mercurial-scm.org/D2018

# rewriteutil.py - utility functions for rewriting changesets
#
# Copyright 2017 Octobus <[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.

from __future__ import absolute_import

from .i18n import _

from . import (
    error,
    node,
    obsolete,
    revset,
)

def precheck(repo, revs, action='rewrite'):
    """check if revs can be rewritten
    action is used to control the error message.

    Make sure this function is called after taking the lock.
    """
    if node.nullrev in revs:
        msg = _("cannot %s null changeset") % (action)
        hint = _("no changeset checked out")
        raise error.Abort(msg, hint=hint)

    publicrevs = repo.revs('%ld and public()', revs)
    if len(repo[None].parents()) > 1:
        raise error.Abort(_("cannot %s while merging") % action)

    if publicrevs:
        msg = _("cannot %s public changesets") % (action)
        hint = _("see 'hg help phases' for details")
        raise error.Abort(msg, hint=hint)

    newunstable = disallowednewunstable(repo, revs)
    if newunstable:
        raise error.Abort(_("cannot %s changeset with children") % action)

def disallowednewunstable(repo, revs):
    """Checks whether editing the revs will create new unstable changesets and
    are we allowed to create them.

    To allow new unstable changesets, set the config:
        `experimental.evolution.allowunstable=True`
    """
    allowunstable = obsolete.isenabled(repo, obsolete.allowunstableopt)
    if allowunstable:
        return revset.baseset()
    return repo.revs("(%ld::) - %ld", revs, revs)