mercurial/scmwindows.py

py3: add "b" prefix to string literals related to module policy

String literals without explicit prefix in __init__.py and policy.py
are treated as unicode object on Python3, because these modules are
loaded before setup of our specific code transformation (the later
module is imported at the beginning of __init__.py).

BTW, "modulepolicy" in __init__.py is initialized by "policy.policy".

This causes issues below;

  - checking "policy" value in other modules causes unintentional result

    For example, "b'py' not in (u'c', u'py')" returns True
    unintentionally on Python3.

  - writing "policy" out fails at conversion from unicode to bytes

    62939e0148f1 fixed this issue for default code path, but "policy"
    can be overridden by HGMODULEPOLICY environment variable (it should
    be rare case for developer using Python3, though).

This patch does:

  - add "b" prefix to all string literals, which are related to module
    policy, in modules above.

  - check existence of HGMODULEPOLICY, and overwrite "policy" only if
    it exists

    For simplicity, this patch omits checking "supports_bytes_environ",
    switching os.environ/os.environb, and so on (Yuya agreed this in
    personal talking)

from __future__ import absolute_import

import os

from . import (
    encoding,
    osutil,
    pycompat,
    util,
    win32,
)

try:
    import _winreg as winreg
    winreg.CloseKey
except ImportError:
    import winreg

def systemrcpath():
    '''return default os-specific hgrc search path'''
    rcpath = []
    filename = util.executablepath()
    # Use mercurial.ini found in directory with hg.exe
    progrc = os.path.join(os.path.dirname(filename), 'mercurial.ini')
    rcpath.append(progrc)
    # Use hgrc.d found in directory with hg.exe
    progrcd = os.path.join(os.path.dirname(filename), 'hgrc.d')
    if os.path.isdir(progrcd):
        for f, kind in osutil.listdir(progrcd):
            if f.endswith('.rc'):
                rcpath.append(os.path.join(progrcd, f))
    # else look for a system rcpath in the registry
    value = util.lookupreg('SOFTWARE\\Mercurial', None,
                           winreg.HKEY_LOCAL_MACHINE)
    if not isinstance(value, str) or not value:
        return rcpath
    value = util.localpath(value)
    for p in value.split(pycompat.ospathsep):
        if p.lower().endswith('mercurial.ini'):
            rcpath.append(p)
        elif os.path.isdir(p):
            for f, kind in osutil.listdir(p):
                if f.endswith('.rc'):
                    rcpath.append(os.path.join(p, f))
    return rcpath

def userrcpath():
    '''return os-specific hgrc search path to the user dir'''
    home = os.path.expanduser('~')
    path = [os.path.join(home, 'mercurial.ini'),
            os.path.join(home, '.hgrc')]
    userprofile = encoding.environ.get('USERPROFILE')
    if userprofile and userprofile != home:
        path.append(os.path.join(userprofile, 'mercurial.ini'))
        path.append(os.path.join(userprofile, '.hgrc'))
    return path

def termsize(ui):
    return win32.termsize()