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##############################################################################
# Copyright (c) 2020 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
##############################################################################
"""
Interface definitions paralleling the abstract base classes defined in
:mod:`collections.abc`.

After this module is imported, the standard library types will declare that
they implement the appropriate interface. While most standard library types
will properly implement that interface (that is, ``verifyObject(ISequence,
list()))`` will pass, for example), a few might not:

    - `memoryview` doesn't feature all the defined methods of
      ``ISequence`` such as ``count``; it is still declared to provide
      ``ISequence`` though.

    - `collections.deque.pop` doesn't accept the ``index`` argument of
      `collections.abc.MutableSequence.pop`

    - `range.index` does not accept the ``start`` and ``stop`` arguments.

.. versionadded:: 5.0.0
"""

import sys
from abc import ABCMeta
from collections import OrderedDict
from collections import UserDict
from collections import UserList
from collections import UserString
from collections import abc

from zope.interface._compat import PY313_OR_OLDER
from zope.interface.common import ABCInterface
from zope.interface.common import optional


# pylint:disable=inherit-non-class,
# pylint:disable=no-self-argument,no-method-argument
# pylint:disable=unexpected-special-method-signature
# pylint:disable=no-value-for-parameter


def _new_in_ver(name, ver,
                bases_if_missing=(ABCMeta,),
                register_if_missing=()):
    if ver:
        return getattr(abc, name)

    # TODO: It's a shame to have to repeat the bases when
    # the ABC is missing. Can we DRY that?
    missing = ABCMeta(name, bases_if_missing, {
        '__doc__': "The ABC %s is not defined in this version of Python." % (
            name
        ),
    })

    for c in register_if_missing:
        missing.register(c)

    return missing


__all__ = [
    'IAsyncGenerator',
    'IAsyncIterable',
    'IAsyncIterator',
    'IAwaitable',
    'ICollection',
    'IContainer',
    'ICoroutine',
    'IGenerator',
    'IHashable',
    'IItemsView',
    'IIterable',
    'IIterator',
    'IKeysView',
    'IMapping',
    'IMappingView',
    'IMutableMapping',
    'IMutableSequence',
    'IMutableSet',
    'IReversible',
    'ISequence',
    'ISet',
    'ISized',
    'IValuesView',
]


class IContainer(ABCInterface):
    abc = abc.Container

    @optional
    def __contains__(other):
        """
        Optional method. If not provided, the interpreter will use
        ``__iter__`` or the old ``__getitem__`` protocol
        to implement ``in``.
        """


class IHashable(ABCInterface):
    abc = abc.Hashable


class IIterable(ABCInterface):
    abc = abc.Iterable

    @optional
    def __iter__():
        """
        Optional method. If not provided, the interpreter will
        implement `iter` using the old ``__getitem__`` protocol.
        """


class IIterator(IIterable):
    abc = abc.Iterator


class IReversible(IIterable):
    abc = _new_in_ver('Reversible', True, (IIterable.getABC(),))

    @optional
    def __reversed__():
        """
        Optional method. If this isn't present, the interpreter
        will use ``__len__`` and ``__getitem__`` to implement the
        `reversed` builtin.
        """


class IGenerator(IIterator):
    # New in Python 3.5
    abc = _new_in_ver('Generator', True, (IIterator.getABC(),))


class ISized(ABCInterface):
    abc = abc.Sized


# ICallable is not defined because there's no standard signature.


class ICollection(ISized,
                  IIterable,
                  IContainer):
    abc = _new_in_ver(
        'Collection',
        True,
        (ISized.getABC(), IIterable.getABC(), IContainer.getABC())
    )


class ISequence(IReversible,
                ICollection):
    abc = abc.Sequence
    extra_classes = (UserString,)
    # On Python 2, basestring was registered as an ISequence, and
    # its subclass str is an IByteString. If we also register str as
    # an ISequence, that tends to lead to inconsistent resolution order.
    ignored_classes = ()

    @optional
    def __reversed__():
        """
        Optional method. If this isn't present, the interpreter
        will use ``__len__`` and ``__getitem__`` to implement the
        `reversed` builtin.
        """

    @optional
    def __iter__():
        """
        Optional method. If not provided, the interpreter will
        implement `iter` using the old ``__getitem__`` protocol.
        """


class IMutableSequence(ISequence):
    abc = abc.MutableSequence
    extra_classes = (UserList,)


if PY313_OR_OLDER:
    class IByteString(ISequence):
        """
        This unifies `bytes` and `bytearray`.
        """
        abc = _new_in_ver(
            'ByteString', True, (ISequence.getABC(),), (bytes, bytearray),
        )


class ISet(ICollection):
    abc = abc.Set


class IMutableSet(ISet):
    abc = abc.MutableSet


class IMapping(ICollection):
    abc = abc.Mapping
    extra_classes = (dict,)
    # OrderedDict is a subclass of dict. On CPython 2,
    # it winds up registered as a IMutableMapping, which
    # produces an inconsistent IRO if we also try to register it
    # here.
    ignored_classes = (OrderedDict,)


class IMutableMapping(IMapping):
    abc = abc.MutableMapping
    extra_classes = (dict, UserDict,)
    ignored_classes = (OrderedDict,)


class IMappingView(ISized):
    abc = abc.MappingView


class IItemsView(IMappingView, ISet):
    abc = abc.ItemsView


class IKeysView(IMappingView, ISet):
    abc = abc.KeysView


class IValuesView(IMappingView, ICollection):
    abc = abc.ValuesView

    @optional
    def __contains__(other):
        """
        Optional method. If not provided, the interpreter will use
        ``__iter__`` or the old ``__len__`` and ``__getitem__`` protocol
        to implement ``in``.
        """


class IAwaitable(ABCInterface):
    abc = _new_in_ver('Awaitable', True)


class ICoroutine(IAwaitable):
    abc = _new_in_ver('Coroutine', True)


class IAsyncIterable(ABCInterface):
    abc = _new_in_ver('AsyncIterable', True)


class IAsyncIterator(IAsyncIterable):
    abc = _new_in_ver('AsyncIterator', True)


class IAsyncGenerator(IAsyncIterator):
    abc = _new_in_ver('AsyncGenerator', True)