view mercurial/utils/interfaceutil.py @ 40793:64cdfcc73706

cache: create `cache` directory at init time

The cache directory will be needed very quickly, so it seems simpler to create
it early to make sure it has the same owner and permission than the other
directory in the repository.

# interfaceutil.py - Utilities for declaring interfaces.
#
# Copyright 2018 Gregory Szorc <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

# zope.interface imposes a run-time cost due to module import overhead and
# bookkeeping for declaring interfaces. So, we use stubs for various
# zope.interface primitives unless instructed otherwise.

from __future__ import absolute_import

from .. import (
    encoding,
)

if encoding.environ.get('HGREALINTERFACES'):
    from ..thirdparty.zope import (
        interface as zi,
    )

    Attribute = zi.Attribute
    Interface = zi.Interface
    implementer = zi.implementer
else:
    class Attribute(object):
        def __init__(self, __name__, __doc__=''):
            pass

    class Interface(object):
        def __init__(self, name, bases=(), attrs=None, __doc__=None,
                 __module__=None):
            pass

    def implementer(*ifaces):
        def wrapper(cls):
            return cls

        return wrapper