tests/pullext.py

help: get helptext/ data from `resources` module if available

For PyOxidizer, we need to read configs using the `resources`
module. This patch makes it so we use that module if available
(i.e. Python >= 3.7). It does that by adding a new `open_resource()`
function to our `resourceutil` module.

Tested by running `$PYTHON ./hg help pager` for each $PYTHON in
{python2, python3.6, python3.7}.

Differential Revision: https://phab.mercurial-scm.org/D7622

# 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,
)
from mercurial.interfaces import repository


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

    if kwargs.get('depth'):
        try:
            kwargs['depth'] = int(kwargs['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)