interfaces: convert the zope `Attribute` attrs to regular fields At this point, we should have a useful protocol class. The file syntax requires the type to be supplied for any fields that are declared, but we'll leave the complex ones partially unspecified for now, for simplicity. (Also, the things documented as `Callable` are really as future type annotating worked showed- roll with it for now, but they're marked as TODO for fixing later.) All of the fields and all of the attrs will need type annotations, or the type rules say they are considered to be `Any`. That can be done in a separate pass, possibly applying the `dirstate.pyi` file generated from the concrete class. The first cut of this turned the `interfaceutil.Attribute` fields into plain fields, and thus the types on them. PyCharm flagged a few things as having incompatible signatures when the concrete dirstate class subclassed this, when the concrete class has them declared as `@property`. So they've been changed to `@property` here in those cases. The remaining fields that are decorated in the concrete class have comments noting the differences. We'll see if they need to be changed going forward, but leave them for now. We'll be in trouble if the `@util.propertycache` is needed, because we can't import that module here at runtime, due to circular imports.

# util.py - Utilities for declaring interfaces.
#
# Copyright 2018 Gregory Szorc <gregory.szorc@gmail.com>
#
# 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 annotations

from .. import encoding

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

    Attribute = zi.Attribute
    Interface = zi.Interface
    implementer = zi.implementer
else:

    class Attribute:
        def __init__(self, __name__, __doc__=b''):
            pass

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

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

        return wrapper