hgdemandimport/__init__.py

setup: prevent setuptools from laying an egg

Previously, test-hghave.t was failing on Windows (and on Linux if
$FORCE_SETUPTOOLS was set) with the following:

  --- c:/Users/Matt/Projects/hg/tests/test-hghave.t
  +++ c:/Users/Matt/Projects/hg/tests/test-hghave.t.err
  @@ -19,7 +19,11 @@
     >   foo
     > EOF
     $ run-tests.py $HGTEST_RUN_TESTS_PURE test-hghaveaddon.t
  +  warning: Testing with unexpected mercurial lib: c:\Users\Matt\Projects\hg\mercurial
  +           (expected ...\hgtests.mu9rou\install\lib\python\mercurial)
     .
  +  warning: Tested with unexpected mercurial lib: c:\Users\Matt\Projects\hg\mercurial
  +           (expected ...\hgtests.mu9rou\install\lib\python\mercurial)

Augie relayed concerns[1] about the first attempt at this, which also excluded
'install_egg_info'.  All that needs to be excluded to avoid the egg and make the
test work is to filter out 'bdist_egg'.  (Actually, the body of this class could
simply be 'pass', and 'bdist_egg' still isn't run.  But that seems to magical.)

Also note that prior to this (and still now), `make clean` doesn't delete the
'mercurial.egg-info' that is generated by `make install`.

[1] https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-May/097668.html

# no-check-commit

# 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.

from __future__ import absolute_import

import sys

if sys.version_info[0] >= 3:
    from . import demandimportpy3 as demandimport
else:
    from . import demandimportpy2 as demandimport

# Extensions can add to this list if necessary.
ignore = [
    '__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__',
    '_ssl', # conditional imports in the stdlib, issue1964
    '_sre', # issue4920
    'rfc822',
    'mimetools',
    'sqlalchemy.events', # has import-time side effects (issue5085)
    # setuptools 8 expects this module to explode early when not on windows
    'distutils.msvc9compiler',
    '__builtin__',
    'builtins',
    'urwid.command_map', # for pudb
    ]

_pypy = '__pypy__' in sys.builtin_module_names

if _pypy:
    ignore.extend([
        # _ctypes.pointer is shadowed by "from ... import pointer" (PyPy 5)
        '_ctypes.pointer',
    ])

demandimport.init(ignore)

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