mercurial/scmposix.py

demandimport: import sub-module relatively as expected (issue5208)

Before this patch, importing sub-module might (1) fail or (2) success
but import incorrect module, because demandimport tries to import
sub-module with level=-1 (on Python 2.x) or level=0 (on Python 3.x),
which is default value of "level" argument at construction of
"_demandmod" proxy object.

  (1) on Python 3.x, importing sub-module always fails to import
      existing sub-module

  (2) both on Python 2.x and 3.x, importing sub-module might import
      same name module on root level unintentionally

      On Python 2.x, existing sub-module is prior to this unexpected
      module. Therefore, this problem hasn't appeared.

To import sub-module relatively as expected, this patch specifies "1"
as import level explicitly at construction of "_demandmod" proxy
object for sub-module.

from __future__ import absolute_import

import os
import sys

from . import (
    osutil,
)

def _rcfiles(path):
    rcs = [os.path.join(path, 'hgrc')]
    rcdir = os.path.join(path, 'hgrc.d')
    try:
        rcs.extend([os.path.join(rcdir, f)
                    for f, kind in osutil.listdir(rcdir)
                    if f.endswith(".rc")])
    except OSError:
        pass
    return rcs

def systemrcpath():
    path = []
    if sys.platform == 'plan9':
        root = 'lib/mercurial'
    else:
        root = 'etc/mercurial'
    # old mod_python does not set sys.argv
    if len(getattr(sys, 'argv', [])) > 0:
        p = os.path.dirname(os.path.dirname(sys.argv[0]))
        if p != '/':
            path.extend(_rcfiles(os.path.join(p, root)))
    path.extend(_rcfiles('/' + root))
    return path

def userrcpath():
    if sys.platform == 'plan9':
        return [os.environ['home'] + '/lib/hgrc']
    else:
        return [os.path.expanduser('~/.hgrc')]