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Merged
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May 18, 2016
Merged

Stop generic subclasses from inheriting __extra__ #223

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25 changes: 22 additions & 3 deletions python2/test_typing.py
View file
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Original file line number Diff line number Diff line change
@@ -1,5 +1,6 @@
from __future__ import absolute_import, unicode_literals

import collections
import pickle
import re
import sys
Expand Down Expand Up @@ -970,13 +971,17 @@ def test_no_list_instantiation(self):
with self.assertRaises(TypeError):
typing.List[int]()

def test_list_subclass_instantiation(self):
def test_list_subclass(self):

class MyList(typing.List[int]):
pass

a = MyList()
self.assertIsInstance(a, MyList)
self.assertIsInstance(a, typing.Sequence)

self.assertIsSubclass(MyList, list)
self.assertNotIsSubclass(list, MyList)

def test_no_dict_instantiation(self):
with self.assertRaises(TypeError):
Expand All @@ -986,13 +991,17 @@ def test_no_dict_instantiation(self):
with self.assertRaises(TypeError):
typing.Dict[str, int]()

def test_dict_subclass_instantiation(self):
def test_dict_subclass(self):

class MyDict(typing.Dict[str, int]):
pass

d = MyDict()
self.assertIsInstance(d, MyDict)
self.assertIsInstance(d, typing.MutableMapping)

self.assertIsSubclass(MyDict, dict)
self.assertNotIsSubclass(dict, MyDict)

def test_no_defaultdict_instantiation(self):
with self.assertRaises(TypeError):
Expand All @@ -1002,14 +1011,17 @@ def test_no_defaultdict_instantiation(self):
with self.assertRaises(TypeError):
typing.DefaultDict[str, int]()

def test_defaultdict_subclass_instantiation(self):
def test_defaultdict_subclass(self):

class MyDefDict(typing.DefaultDict[str, int]):
pass

dd = MyDefDict()
self.assertIsInstance(dd, MyDefDict)

self.assertIsSubclass(MyDefDict, collections.defaultdict)
self.assertNotIsSubclass(collections.defaultdict, MyDefDict)

def test_no_set_instantiation(self):
with self.assertRaises(TypeError):
typing.Set()
Expand Down Expand Up @@ -1090,6 +1102,13 @@ def __len__(self):
self.assertEqual(len(MMB[str, str]()), 0)
self.assertEqual(len(MMB[KT, VT]()), 0)

self.assertNotIsSubclass(dict, MMA)
self.assertNotIsSubclass(dict, MMB)

self.assertIsSubclass(MMA, typing.Mapping)
self.assertIsSubclass(MMB, typing.Mapping)
self.assertIsSubclass(MMC, typing.Mapping)


class NamedTupleTests(BaseTestCase):

Expand Down
14 changes: 8 additions & 6 deletions python2/typing.py
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Original file line number Diff line number Diff line change
Expand Up @@ -911,8 +911,6 @@ def _next_in_mro(cls):
class GenericMeta(TypingMeta, abc.ABCMeta):
"""Metaclass for generic types."""

__extra__ = None

def __new__(cls, name, bases, namespace,
tvars=None, args=None, origin=None, extra=None):
self = super(GenericMeta, cls).__new__(cls, name, bases, namespace)
Expand Down Expand Up @@ -960,10 +958,7 @@ def __new__(cls, name, bases, namespace,
self.__parameters__ = tvars
self.__args__ = args
self.__origin__ = origin
if extra is not None:
self.__extra__ = extra
# Else __extra__ is inherited, eventually from the
# (meta-)class default above.
self.__extra__ = namespace.get('__extra__')
# Speed hack (https://github.com/python/typing/issues/196).
self.__next_in_mro__ = _next_in_mro(self)
return self
Expand Down Expand Up @@ -1289,6 +1284,7 @@ def _get_protocol_attrs(self):
attr != '__next_in_mro__' and
attr != '__parameters__' and
attr != '__origin__' and
attr != '__extra__' and
attr != '__module__'):
attrs.add(attr)

Expand Down Expand Up @@ -1414,10 +1410,12 @@ class ByteString(Sequence[int]):
pass


ByteString.register(str)
ByteString.register(bytearray)


class List(list, MutableSequence[T]):
__extra__ = list

def __new__(cls, *args, **kwds):
if _geqv(cls, List):
Expand All @@ -1427,6 +1425,7 @@ def __new__(cls, *args, **kwds):


class Set(set, MutableSet[T]):
__extra__ = set

def __new__(cls, *args, **kwds):
if _geqv(cls, Set):
Expand All @@ -1452,6 +1451,7 @@ def __subclasscheck__(self, cls):
class FrozenSet(frozenset, AbstractSet[T_co]):
__metaclass__ = _FrozenSetMeta
__slots__ = ()
__extra__ = frozenset

def __new__(cls, *args, **kwds):
if _geqv(cls, FrozenSet):
Expand Down Expand Up @@ -1479,6 +1479,7 @@ class ValuesView(MappingView[VT_co]):


class Dict(dict, MutableMapping[KT, VT]):
__extra__ = dict

def __new__(cls, *args, **kwds):
if _geqv(cls, Dict):
Expand All @@ -1488,6 +1489,7 @@ def __new__(cls, *args, **kwds):


class DefaultDict(collections.defaultdict, MutableMapping[KT, VT]):
__extra__ = collections.defaultdict

def __new__(cls, *args, **kwds):
if _geqv(cls, DefaultDict):
Expand Down
25 changes: 22 additions & 3 deletions src/test_typing.py
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,4 +1,5 @@
import contextlib
import collections
import pickle
import re
import sys
Expand Down Expand Up @@ -1218,13 +1219,17 @@ def test_no_list_instantiation(self):
with self.assertRaises(TypeError):
typing.List[int]()

def test_list_subclass_instantiation(self):
def test_list_subclass(self):

class MyList(typing.List[int]):
pass

a = MyList()
self.assertIsInstance(a, MyList)
self.assertIsInstance(a, typing.Sequence)

self.assertIsSubclass(MyList, list)
self.assertNotIsSubclass(list, MyList)

def test_no_dict_instantiation(self):
with self.assertRaises(TypeError):
Expand All @@ -1234,13 +1239,17 @@ def test_no_dict_instantiation(self):
with self.assertRaises(TypeError):
typing.Dict[str, int]()

def test_dict_subclass_instantiation(self):
def test_dict_subclass(self):

class MyDict(typing.Dict[str, int]):
pass

d = MyDict()
self.assertIsInstance(d, MyDict)
self.assertIsInstance(d, typing.MutableMapping)

self.assertIsSubclass(MyDict, dict)
self.assertNotIsSubclass(dict, MyDict)

def test_no_defaultdict_instantiation(self):
with self.assertRaises(TypeError):
Expand All @@ -1250,14 +1259,17 @@ def test_no_defaultdict_instantiation(self):
with self.assertRaises(TypeError):
typing.DefaultDict[str, int]()

def test_defaultdict_subclass_instantiation(self):
def test_defaultdict_subclass(self):

class MyDefDict(typing.DefaultDict[str, int]):
pass

dd = MyDefDict()
self.assertIsInstance(dd, MyDefDict)

self.assertIsSubclass(MyDefDict, collections.defaultdict)
self.assertNotIsSubclass(collections.defaultdict, MyDefDict)

def test_no_set_instantiation(self):
with self.assertRaises(TypeError):
typing.Set()
Expand Down Expand Up @@ -1338,6 +1350,13 @@ def __len__(self):
self.assertEqual(len(MMB[str, str]()), 0)
self.assertEqual(len(MMB[KT, VT]()), 0)

self.assertNotIsSubclass(dict, MMA)
self.assertNotIsSubclass(dict, MMB)

self.assertIsSubclass(MMA, typing.Mapping)
self.assertIsSubclass(MMB, typing.Mapping)
self.assertIsSubclass(MMC, typing.Mapping)


class OtherABCTests(BaseTestCase):

Expand Down
20 changes: 9 additions & 11 deletions src/typing.py
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -894,8 +894,6 @@ def _next_in_mro(cls):
class GenericMeta(TypingMeta, abc.ABCMeta):
"""Metaclass for generic types."""

__extra__ = None

def __new__(cls, name, bases, namespace,
tvars=None, args=None, origin=None, extra=None):
self = super().__new__(cls, name, bases, namespace, _root=True)
Expand Down Expand Up @@ -943,10 +941,7 @@ def __new__(cls, name, bases, namespace,
self.__parameters__ = tvars
self.__args__ = args
self.__origin__ = origin
if extra is not None:
self.__extra__ = extra
# Else __extra__ is inherited, eventually from the
# (meta-)class default above.
self.__extra__ = extra
# Speed hack (https://github.com/python/typing/issues/196).
self.__next_in_mro__ = _next_in_mro(self)
return self
Expand Down Expand Up @@ -1307,6 +1302,7 @@ def _get_protocol_attrs(self):
attr != '__next_in_mro__' and
attr != '__parameters__' and
attr != '__origin__' and
attr != '__extra__' and
attr != '__module__'):
attrs.add(attr)

Expand Down Expand Up @@ -1470,7 +1466,7 @@ class ByteString(Sequence[int], extra=collections_abc.ByteString):
ByteString.register(type(memoryview(b'')))


class List(list, MutableSequence[T]):
class List(list, MutableSequence[T], extra=list):

def __new__(cls, *args, **kwds):
if _geqv(cls, List):
Expand All @@ -1479,7 +1475,7 @@ def __new__(cls, *args, **kwds):
return list.__new__(cls, *args, **kwds)


class Set(set, MutableSet[T]):
class Set(set, MutableSet[T], extra=set):

def __new__(cls, *args, **kwds):
if _geqv(cls, Set):
Expand All @@ -1502,7 +1498,8 @@ def __subclasscheck__(self, cls):
return super().__subclasscheck__(cls)


class FrozenSet(frozenset, AbstractSet[T_co], metaclass=_FrozenSetMeta):
class FrozenSet(frozenset, AbstractSet[T_co], metaclass=_FrozenSetMeta,
extra=frozenset):
__slots__ = ()

def __new__(cls, *args, **kwds):
Expand Down Expand Up @@ -1538,15 +1535,16 @@ class ContextManager(Generic[T_co], extra=contextlib.AbstractContextManager):
__all__.append('ContextManager')


class Dict(dict, MutableMapping[KT, VT]):
class Dict(dict, MutableMapping[KT, VT], extra=dict):

def __new__(cls, *args, **kwds):
if _geqv(cls, Dict):
raise TypeError("Type Dict cannot be instantiated; "
"use dict() instead")
return dict.__new__(cls, *args, **kwds)

class DefaultDict(collections.defaultdict, MutableMapping[KT, VT]):
class DefaultDict(collections.defaultdict, MutableMapping[KT, VT],
extra=collections.defaultdict):

def __new__(cls, *args, **kwds):
if _geqv(cls, DefaultDict):
Expand Down