view mercurial/utils/interfaceutil.py @ 38850:6104b203bec8

index: replace insert(-1, e) method by append(e) method

I want to make index[len(index) - 1] be the tip revision, not null
revision as it is today. insert(-1, e) will then make little
sense. Since insert() currently requires the first argument to be -1,
it seems simpler to replace it by a method that allows insertion only
at the end.

Note that revlogoldindex already has this method (by virtue of
extending list).

Differential Revision: https://phab.mercurial-scm.org/D4021

# 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