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import unittest
class TestLoadAttrCache(unittest.TestCase):
def test_descriptor_added_after_optimization(self):
class Descriptor:
pass
class C:
def __init__(self):
self.x = 1
x = Descriptor()
def f(o):
return o.x
o = C()
for i in range(1025):
assert f(o) == 1
Descriptor.__get__ = lambda self, instance, value: 2
Descriptor.__set__ = lambda *args: None
self.assertEqual(f(o), 2)
def test_metaclass_descriptor_added_after_optimization(self):
class Descriptor:
pass
class Metaclass(type):
attribute = Descriptor()
class Class(metaclass=Metaclass):
attribute = True
def __get__(self, instance, owner):
return False
def __set__(self, instance, value):
return None
def f():
return Class.attribute
for _ in range(1025):
self.assertTrue(f())
Descriptor.__get__ = __get__
Descriptor.__set__ = __set__
for _ in range(1025):
self.assertFalse(f())
def test_metaclass_descriptor_shadows_class_attribute(self):
class Metaclass(type):
@property
def attribute(self):
return True
class Class(metaclass=Metaclass):
attribute = False
def f():
return Class.attribute
for _ in range(1025):
self.assertTrue(f())
def test_metaclass_set_descriptor_after_optimization(self):
class Metaclass(type):
pass
class Class(metaclass=Metaclass):
attribute = True
@property
def attribute(self):
return False
def f():
return Class.attribute
for _ in range(1025):
self.assertTrue(f())
Metaclass.attribute = attribute
for _ in range(1025):
self.assertFalse(f())
def test_metaclass_del_descriptor_after_optimization(self):
class Metaclass(type):
@property
def attribute(self):
return True
class Class(metaclass=Metaclass):
attribute = False
def f():
return Class.attribute
for _ in range(1025):
self.assertTrue(f())
del Metaclass.attribute
for _ in range(1025):
self.assertFalse(f())
def test_type_descriptor_shadows_attribute_method(self):
class Class:
mro = None
def f():
return Class.mro
for _ in range(1025):
self.assertIsNone(f())
def test_type_descriptor_shadows_attribute_member(self):
class Class:
__base__ = None
def f():
return Class.__base__
for _ in range(1025):
self.assertIs(f(), object)
def test_type_descriptor_shadows_attribute_getset(self):
class Class:
__name__ = "Spam"
def f():
return Class.__name__
for _ in range(1025):
self.assertEqual(f(), "Class")
def test_metaclass_getattribute(self):
class Metaclass(type):
def __getattribute__(self, name):
return True
class Class(metaclass=Metaclass):
attribute = False
def f():
return Class.attribute
for _ in range(1025):
self.assertTrue(f())
def test_metaclass_swap(self):
class OldMetaclass(type):
@property
def attribute(self):
return True
class NewMetaclass(type):
@property
def attribute(self):
return False
class Class(metaclass=OldMetaclass):
pass
def f():
return Class.attribute
for _ in range(1025):
self.assertTrue(f())
Class.__class__ = NewMetaclass
for _ in range(1025):
self.assertFalse(f())
def test_load_shadowing_slot_should_raise_type_error(self):
class Class:
__slots__ = ("slot",)
class Sneaky:
__slots__ = ("shadowed",)
shadowing = Class.slot
def f(o):
o.shadowing
o = Sneaky()
o.shadowed = 42
for _ in range(1025):
with self.assertRaises(TypeError):
f(o)
def test_store_shadowing_slot_should_raise_type_error(self):
class Class:
__slots__ = ("slot",)
class Sneaky:
__slots__ = ("shadowed",)
shadowing = Class.slot
def f(o):
o.shadowing = 42
o = Sneaky()
for _ in range(1025):
with self.assertRaises(TypeError):
f(o)
def test_load_borrowed_slot_should_not_crash(self):
class Class:
__slots__ = ("slot",)
class Sneaky:
borrowed = Class.slot
def f(o):
o.borrowed
o = Sneaky()
for _ in range(1025):
with self.assertRaises(TypeError):
f(o)
def test_store_borrowed_slot_should_not_crash(self):
class Class:
__slots__ = ("slot",)
class Sneaky:
borrowed = Class.slot
def f(o):
o.borrowed = 42
o = Sneaky()
for _ in range(1025):
with self.assertRaises(TypeError):
f(o)
class TestLoadMethodCache(unittest.TestCase):
def test_descriptor_added_after_optimization(self):
class Descriptor:
pass
class Class:
attribute = Descriptor()
def __get__(self, instance, owner):
return lambda: False
def __set__(self, instance, value):
return None
def attribute():
return True
instance = Class()
instance.attribute = attribute
def f():
return instance.attribute()
for _ in range(1025):
self.assertTrue(f())
Descriptor.__get__ = __get__
Descriptor.__set__ = __set__
for _ in range(1025):
self.assertFalse(f())
def test_metaclass_descriptor_added_after_optimization(self):
class Descriptor:
pass
class Metaclass(type):
attribute = Descriptor()
class Class(metaclass=Metaclass):
def attribute():
return True
def __get__(self, instance, owner):
return lambda: False
def __set__(self, instance, value):
return None
def f():
return Class.attribute()
for _ in range(1025):
self.assertTrue(f())
Descriptor.__get__ = __get__
Descriptor.__set__ = __set__
for _ in range(1025):
self.assertFalse(f())
def test_metaclass_descriptor_shadows_class_attribute(self):
class Metaclass(type):
@property
def attribute(self):
return lambda: True
class Class(metaclass=Metaclass):
def attribute():
return False
def f():
return Class.attribute()
for _ in range(1025):
self.assertTrue(f())
def test_metaclass_set_descriptor_after_optimization(self):
class Metaclass(type):
pass
class Class(metaclass=Metaclass):
def attribute():
return True
@property
def attribute(self):
return lambda: False
def f():
return Class.attribute()
for _ in range(1025):
self.assertTrue(f())
Metaclass.attribute = attribute
for _ in range(1025):
self.assertFalse(f())
def test_metaclass_del_descriptor_after_optimization(self):
class Metaclass(type):
@property
def attribute(self):
return lambda: True
class Class(metaclass=Metaclass):
def attribute():
return False
def f():
return Class.attribute()
for _ in range(1025):
self.assertTrue(f())
del Metaclass.attribute
for _ in range(1025):
self.assertFalse(f())
def test_type_descriptor_shadows_attribute_method(self):
class Class:
def mro():
return ["Spam", "eggs"]
def f():
return Class.mro()
for _ in range(1025):
self.assertEqual(f(), ["Spam", "eggs"])
def test_type_descriptor_shadows_attribute_member(self):
class Class:
def __base__():
return "Spam"
def f():
return Class.__base__()
for _ in range(1025):
self.assertNotEqual(f(), "Spam")
def test_metaclass_getattribute(self):
class Metaclass(type):
def __getattribute__(self, name):
return lambda: True
class Class(metaclass=Metaclass):
def attribute():
return False
def f():
return Class.attribute()
for _ in range(1025):
self.assertTrue(f())
def test_metaclass_swap(self):
class OldMetaclass(type):
@property
def attribute(self):
return lambda: True
class NewMetaclass(type):
@property
def attribute(self):
return lambda: False
class Class(metaclass=OldMetaclass):
pass
def f():
return Class.attribute()
for _ in range(1025):
self.assertTrue(f())
Class.__class__ = NewMetaclass
for _ in range(1025):
self.assertFalse(f())
class TestCallCache(unittest.TestCase):
def test_too_many_defaults_0(self):
def f():
pass
f.__defaults__ = (None,)
for _ in range(1025):
f()
def test_too_many_defaults_1(self):
def f(x):
pass
f.__defaults__ = (None, None)
for _ in range(1025):
f(None)
f()
def test_too_many_defaults_2(self):
def f(x, y):
pass
f.__defaults__ = (None, None, None)
for _ in range(1025):
f(None, None)
f(None)
f()
if __name__ == "__main__":
import unittest
unittest.main()
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