tests/pullext.py

revlog: always enable generaldelta on version 2 revlogs

This commit starts the process of diverging version 2 revlogs
from version 1 revlogs.

generaldelta is a useful feature and has been enabled by
default for ages. I can't think of a good reason why the
feature should be disabled. Yes, it is true changelogs
today don't have generaldelta enabled. But that's because
they don't have delta chains enabled, so generaldelta makes
no sense there.

This commit makes generaldelta always enabled on version 2
revlogs.

As part of this, one-off code in changelog.py mucking with
revlog.version had to be made conditional on the revlog
version, as we don't want to change revlog feature
flags on version 2 revlogs. The fact this code exists
is horrible and stems from revlog options being shared by
the opener. We probably want a better API here. But that can
wait for another patch.

Differential Revision: https://phab.mercurial-scm.org/D5561

# pullext.py - Simple extension to test pulling
#
# Copyright 2018 Gregory Szorc <[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 mercurial.i18n import _
from mercurial import (
    commands,
    error,
    extensions,
    localrepo,
    repository,
)

def clonecommand(orig, ui, repo, *args, **kwargs):
    if kwargs.get(r'include') or kwargs.get(r'exclude'):
        kwargs[r'narrow'] = True

    if kwargs.get(r'depth'):
        try:
            kwargs[r'depth'] = int(kwargs[r'depth'])
        except ValueError:
            raise error.Abort(_('--depth must be an integer'))

    return orig(ui, repo, *args, **kwargs)

def featuresetup(ui, features):
    features.add(repository.NARROW_REQUIREMENT)

def extsetup(ui):
    entry = extensions.wrapcommand(commands.table, b'clone', clonecommand)

    hasinclude = any(x[1] == b'include' for x in entry[1])
    hasdepth = any(x[1] == b'depth' for x in entry[1])

    if not hasinclude:
        entry[1].append((b'', b'include', [],
                         _(b'pattern of file/directory to clone')))
        entry[1].append((b'', b'exclude', [],
                         _(b'pattern of file/directory to not clone')))

    if not hasdepth:
        entry[1].append((b'', b'depth', b'',
                         _(b'ancestry depth of changesets to fetch')))

    localrepo.featuresetupfuncs.add(featuresetup)