view hgdemandimport/__init__.py @ 37911:0a79fb64118e

revset: use resolvehexnodeidprefix() in id() predicate (BC)

We now have a public method for this purpose, so we don't need to
access the private revlog._partialmatch(). Also, I'll probably make
some changes to resolvehexnodeidprefix() later, and I want those to be
reflected by the id() predicate.

Note that this breaks a test case, because we now resolve the prefix
in the unfiltered repo and get an ambiguous lookup, which results in
no revision being added to the revset. The test case was already
documented to be broken even though it wasn't. It's important to note
that {shortest(node)} already uses the unfiltered repo, so we're not
going to break people who get the prefix from there.

I think we may not want to ever use shortest() in the filtered
repo. It seems unlikely to be enough of a win to matter much. For
example, in my hg repo, it would save me only 0.2 hex digits. In
another repo that only I modify, it saves a little more, but it's
still only 0.29 hex digits. It seems unlikely that people will prune
enough commits that only 1/16 of the commits are visible (which is
what it would take a to save a single hex digit). Instead, I'm working
on another approach: allow ambiguous matches to be disambiguated
within a user-specified revset. Whether or not that pans out, I hope
we're okay with this little change in behavior for now and we can
decide what to do about it later.

Differential Revision: https://phab.mercurial-scm.org/D3311

# 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 os
import sys

if sys.version_info[0] >= 3:
    from . import demandimportpy3 as demandimport
else:
    from . import demandimportpy2 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__',
    '_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:
    # _ctypes.pointer is shadowed by "from ... import pointer" (PyPy 5)
    IGNORES.add('_ctypes.pointer')

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()