hgdemandimport/__init__.py

setup: drop the hack to disable linker warning 4197 on Windows

I don't see this when building on Windows with py3.8 or py3.12, so either the
code was fixed, or (more likely) the compiler stopped warning about it some time
after VS 2008.  If we do have to put this back, it would probably be better to
put a `#pragma` in a header file somewhere, and avoid `setuptools` technical
debt.

# hgdemandimport - global demand-loading of modules for Mercurial
#
# Copyright 2017 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.

'''demandimport - automatic demand-loading of modules'''

# This is in a separate package from mercurial because in Python 3,
# demand loading is per-package. Keeping demandimport in the mercurial package
# would disable demand loading for any modules in mercurial.


import os
import sys

from . import demandimportpy3 as demandimport

# Full module names which can't be lazy imported.
# Extensions can add to this set.
IGNORES = {
    '__future__',
    '_hashlib',
    # ImportError during pkg_resources/__init__.py:fixup_namespace_package
    '_imp',
    '_xmlplus',
    'fcntl',
    'nt',  # pathlib2 tests the existence of built-in 'nt' module
    'win32com.gen_py',
    'win32com.shell',  # 'appdirs' tries to import win32com.shell
    '_winreg',  # 2.7 mimetypes needs immediate ImportError
    'pythoncom',
    # imported by tarfile, not available under Windows
    'pwd',
    'grp',
    # imported by profile, itself imported by hotshot.stats,
    # not available under Windows
    'resource',
    # this trips up many extension authors
    'gtk',
    # setuptools' pkg_resources.py expects "from __main__ import x" to
    # raise ImportError if x not defined
    '__main__',
    '_ast',  # https://bugs.python.org/issue41631
    '_ssl',  # conditional imports in the stdlib, issue1964
    '_sre',  # issue4920
    'rfc822',
    'mimetools',
    'sqlalchemy.events',  # has import-time side effects (issue5085)
    'sqlalchemy.dialects',  # similar problems as above
    # setuptools 8 expects this module to explode early when not on windows
    'distutils.msvc9compiler',
    '__builtin__',
    'builtins',
    'urwid.command_map',  # for pudb
    'lzma',
    # setuptools uses this hack to inject it's own distutils at import time
    'setuptools',
    '_distutils_hack.override',
    # threading is locally imported by importlib.util.LazyLoader.exec_module
    '_weakrefset',
    'warnings',
    'threading',
}

_pypy = '__pypy__' in sys.builtin_module_names

if _pypy:
    # _ctypes.pointer is shadowed by "from ... import pointer" (PyPy 5)
    IGNORES.add('_ctypes.pointer')
    # pure Python module on PyPy, must be loaded to raise ModuleNotFoundError
    # on non-Windows platforms
    IGNORES.add('msvcrt')

demandimport.init(IGNORES)

# Re-export.
isenabled = demandimport.isenabled
disable = demandimport.disable
deactivated = demandimport.deactivated


def enable():
    # chg pre-imports modules so do not enable demandimport for it
    if (
        'CHGINTERNALMARK' not in os.environ
        and os.environ.get('HGDEMANDIMPORT') != 'disable'
    ):
        demandimport.enable()