hgext/commitextras.py

diff: make sure we output stat even when --git is not passed (issue4037) (BC)

Before this patch, `hg diff --stat` will give an empty output. It will not show
the stat information. I debugged and found that the underlying code does not
return the diff header and due to that, other code paths fails to parse that as
a diff.

I looked into why we don't return diff headers in quiet mode and found the
behavior is from 8f8bb77d560e70bcc95577e4dfa877df18d876ab which does not have
any mention about why it is done. We also show the diff headers in git, so I
think it's fine showing diff header in normal diff in quiet mode.

Differential Revision: https://phab.mercurial-scm.org/D6007

# commitextras.py
#
# Copyright 2013 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''adds a new flag extras to commit (ADVANCED)'''

from __future__ import absolute_import

import re

from mercurial.i18n import _
from mercurial import (
    commands,
    error,
    extensions,
    registrar,
    util,
)

cmdtable = {}
command = registrar.command(cmdtable)
testedwith = 'ships-with-hg-core'

usedinternally = {
    'amend_source',
    'branch',
    'close',
    'histedit_source',
    'topic',
    'rebase_source',
    'intermediate-source',
    '__touch-noise__',
    'source',
    'transplant_source',
}

def extsetup(ui):
    entry = extensions.wrapcommand(commands.table, 'commit', _commit)
    options = entry[1]
    options.append(('', 'extra', [],
        _('set a changeset\'s extra values'), _("KEY=VALUE")))

def _commit(orig, ui, repo, *pats, **opts):
    if util.safehasattr(repo, 'unfiltered'):
        repo = repo.unfiltered()
    class repoextra(repo.__class__):
        def commit(self, *innerpats, **inneropts):
            extras = opts.get(r'extra')
            for raw in extras:
                if '=' not in raw:
                    msg = _("unable to parse '%s', should follow "
                            "KEY=VALUE format")
                    raise error.Abort(msg % raw)
                k, v = raw.split('=', 1)
                if not k:
                    msg = _("unable to parse '%s', keys can't be empty")
                    raise error.Abort(msg % raw)
                if re.search(br'[^\w-]', k):
                    msg = _("keys can only contain ascii letters, digits,"
                            " '_' and '-'")
                    raise error.Abort(msg)
                if k in usedinternally:
                    msg = _("key '%s' is used internally, can't be set "
                            "manually")
                    raise error.Abort(msg % k)
                inneropts[r'extra'][k] = v
            return super(repoextra, self).commit(*innerpats, **inneropts)
    repo.__class__ = repoextra
    return orig(ui, repo, *pats, **opts)