513 lines
19 KiB
Python
513 lines
19 KiB
Python
# Copyright 2007 Google, Inc. All Rights Reserved.
|
|
# Licensed to PSF under a Contributor Agreement.
|
|
|
|
# Note: each test is run with Python and C versions of ABCMeta. Except for
|
|
# test_ABC_helper(), which assures that abc.ABC is an instance of abc.ABCMeta.
|
|
|
|
"""Unit tests for abc.py."""
|
|
|
|
import unittest
|
|
|
|
import abc
|
|
import _py_abc
|
|
from inspect import isabstract
|
|
|
|
def test_factory(abc_ABCMeta, abc_get_cache_token):
|
|
class TestLegacyAPI(unittest.TestCase):
|
|
|
|
def test_abstractproperty_basics(self):
|
|
@abc.abstractproperty
|
|
def foo(self): pass
|
|
self.assertTrue(foo.__isabstractmethod__)
|
|
def bar(self): pass
|
|
self.assertFalse(hasattr(bar, "__isabstractmethod__"))
|
|
|
|
class C(metaclass=abc_ABCMeta):
|
|
@abc.abstractproperty
|
|
def foo(self): return 3
|
|
self.assertRaises(TypeError, C)
|
|
class D(C):
|
|
@property
|
|
def foo(self): return super().foo
|
|
self.assertEqual(D().foo, 3)
|
|
self.assertFalse(getattr(D.foo, "__isabstractmethod__", False))
|
|
|
|
def test_abstractclassmethod_basics(self):
|
|
@abc.abstractclassmethod
|
|
def foo(cls): pass
|
|
self.assertTrue(foo.__isabstractmethod__)
|
|
@classmethod
|
|
def bar(cls): pass
|
|
self.assertFalse(getattr(bar, "__isabstractmethod__", False))
|
|
|
|
class C(metaclass=abc_ABCMeta):
|
|
@abc.abstractclassmethod
|
|
def foo(cls): return cls.__name__
|
|
self.assertRaises(TypeError, C)
|
|
class D(C):
|
|
@classmethod
|
|
def foo(cls): return super().foo()
|
|
self.assertEqual(D.foo(), 'D')
|
|
self.assertEqual(D().foo(), 'D')
|
|
|
|
def test_abstractstaticmethod_basics(self):
|
|
@abc.abstractstaticmethod
|
|
def foo(): pass
|
|
self.assertTrue(foo.__isabstractmethod__)
|
|
@staticmethod
|
|
def bar(): pass
|
|
self.assertFalse(getattr(bar, "__isabstractmethod__", False))
|
|
|
|
class C(metaclass=abc_ABCMeta):
|
|
@abc.abstractstaticmethod
|
|
def foo(): return 3
|
|
self.assertRaises(TypeError, C)
|
|
class D(C):
|
|
@staticmethod
|
|
def foo(): return 4
|
|
self.assertEqual(D.foo(), 4)
|
|
self.assertEqual(D().foo(), 4)
|
|
|
|
|
|
class TestABC(unittest.TestCase):
|
|
|
|
def test_ABC_helper(self):
|
|
# create an ABC using the helper class and perform basic checks
|
|
class C(abc.ABC):
|
|
@classmethod
|
|
@abc.abstractmethod
|
|
def foo(cls): return cls.__name__
|
|
self.assertEqual(type(C), abc.ABCMeta)
|
|
self.assertRaises(TypeError, C)
|
|
class D(C):
|
|
@classmethod
|
|
def foo(cls): return super().foo()
|
|
self.assertEqual(D.foo(), 'D')
|
|
|
|
def test_abstractmethod_basics(self):
|
|
@abc.abstractmethod
|
|
def foo(self): pass
|
|
self.assertTrue(foo.__isabstractmethod__)
|
|
def bar(self): pass
|
|
self.assertFalse(hasattr(bar, "__isabstractmethod__"))
|
|
|
|
def test_abstractproperty_basics(self):
|
|
@property
|
|
@abc.abstractmethod
|
|
def foo(self): pass
|
|
self.assertTrue(foo.__isabstractmethod__)
|
|
def bar(self): pass
|
|
self.assertFalse(getattr(bar, "__isabstractmethod__", False))
|
|
|
|
class C(metaclass=abc_ABCMeta):
|
|
@property
|
|
@abc.abstractmethod
|
|
def foo(self): return 3
|
|
self.assertRaises(TypeError, C)
|
|
class D(C):
|
|
@C.foo.getter
|
|
def foo(self): return super().foo
|
|
self.assertEqual(D().foo, 3)
|
|
|
|
def test_abstractclassmethod_basics(self):
|
|
@classmethod
|
|
@abc.abstractmethod
|
|
def foo(cls): pass
|
|
self.assertTrue(foo.__isabstractmethod__)
|
|
@classmethod
|
|
def bar(cls): pass
|
|
self.assertFalse(getattr(bar, "__isabstractmethod__", False))
|
|
|
|
class C(metaclass=abc_ABCMeta):
|
|
@classmethod
|
|
@abc.abstractmethod
|
|
def foo(cls): return cls.__name__
|
|
self.assertRaises(TypeError, C)
|
|
class D(C):
|
|
@classmethod
|
|
def foo(cls): return super().foo()
|
|
self.assertEqual(D.foo(), 'D')
|
|
self.assertEqual(D().foo(), 'D')
|
|
|
|
def test_abstractstaticmethod_basics(self):
|
|
@staticmethod
|
|
@abc.abstractmethod
|
|
def foo(): pass
|
|
self.assertTrue(foo.__isabstractmethod__)
|
|
@staticmethod
|
|
def bar(): pass
|
|
self.assertFalse(getattr(bar, "__isabstractmethod__", False))
|
|
|
|
class C(metaclass=abc_ABCMeta):
|
|
@staticmethod
|
|
@abc.abstractmethod
|
|
def foo(): return 3
|
|
self.assertRaises(TypeError, C)
|
|
class D(C):
|
|
@staticmethod
|
|
def foo(): return 4
|
|
self.assertEqual(D.foo(), 4)
|
|
self.assertEqual(D().foo(), 4)
|
|
|
|
def test_object_new_with_one_abstractmethod(self):
|
|
class C(metaclass=abc_ABCMeta):
|
|
@abc.abstractmethod
|
|
def method_one(self):
|
|
pass
|
|
msg = r"class C with abstract method method_one"
|
|
self.assertRaisesRegex(TypeError, msg, C)
|
|
|
|
def test_object_new_with_many_abstractmethods(self):
|
|
class C(metaclass=abc_ABCMeta):
|
|
@abc.abstractmethod
|
|
def method_one(self):
|
|
pass
|
|
@abc.abstractmethod
|
|
def method_two(self):
|
|
pass
|
|
msg = r"class C with abstract methods method_one, method_two"
|
|
self.assertRaisesRegex(TypeError, msg, C)
|
|
|
|
def test_abstractmethod_integration(self):
|
|
for abstractthing in [abc.abstractmethod, abc.abstractproperty,
|
|
abc.abstractclassmethod,
|
|
abc.abstractstaticmethod]:
|
|
class C(metaclass=abc_ABCMeta):
|
|
@abstractthing
|
|
def foo(self): pass # abstract
|
|
def bar(self): pass # concrete
|
|
self.assertEqual(C.__abstractmethods__, {"foo"})
|
|
self.assertRaises(TypeError, C) # because foo is abstract
|
|
self.assertTrue(isabstract(C))
|
|
class D(C):
|
|
def bar(self): pass # concrete override of concrete
|
|
self.assertEqual(D.__abstractmethods__, {"foo"})
|
|
self.assertRaises(TypeError, D) # because foo is still abstract
|
|
self.assertTrue(isabstract(D))
|
|
class E(D):
|
|
def foo(self): pass
|
|
self.assertEqual(E.__abstractmethods__, set())
|
|
E() # now foo is concrete, too
|
|
self.assertFalse(isabstract(E))
|
|
class F(E):
|
|
@abstractthing
|
|
def bar(self): pass # abstract override of concrete
|
|
self.assertEqual(F.__abstractmethods__, {"bar"})
|
|
self.assertRaises(TypeError, F) # because bar is abstract now
|
|
self.assertTrue(isabstract(F))
|
|
|
|
def test_descriptors_with_abstractmethod(self):
|
|
class C(metaclass=abc_ABCMeta):
|
|
@property
|
|
@abc.abstractmethod
|
|
def foo(self): return 3
|
|
@foo.setter
|
|
@abc.abstractmethod
|
|
def foo(self, val): pass
|
|
self.assertRaises(TypeError, C)
|
|
class D(C):
|
|
@C.foo.getter
|
|
def foo(self): return super().foo
|
|
self.assertRaises(TypeError, D)
|
|
class E(D):
|
|
@D.foo.setter
|
|
def foo(self, val): pass
|
|
self.assertEqual(E().foo, 3)
|
|
# check that the property's __isabstractmethod__ descriptor does the
|
|
# right thing when presented with a value that fails truth testing:
|
|
class NotBool(object):
|
|
def __bool__(self):
|
|
raise ValueError()
|
|
__len__ = __bool__
|
|
with self.assertRaises(ValueError):
|
|
class F(C):
|
|
def bar(self):
|
|
pass
|
|
bar.__isabstractmethod__ = NotBool()
|
|
foo = property(bar)
|
|
|
|
|
|
def test_customdescriptors_with_abstractmethod(self):
|
|
class Descriptor:
|
|
def __init__(self, fget, fset=None):
|
|
self._fget = fget
|
|
self._fset = fset
|
|
def getter(self, callable):
|
|
return Descriptor(callable, self._fget)
|
|
def setter(self, callable):
|
|
return Descriptor(self._fget, callable)
|
|
@property
|
|
def __isabstractmethod__(self):
|
|
return (getattr(self._fget, '__isabstractmethod__', False)
|
|
or getattr(self._fset, '__isabstractmethod__', False))
|
|
class C(metaclass=abc_ABCMeta):
|
|
@Descriptor
|
|
@abc.abstractmethod
|
|
def foo(self): return 3
|
|
@foo.setter
|
|
@abc.abstractmethod
|
|
def foo(self, val): pass
|
|
self.assertRaises(TypeError, C)
|
|
class D(C):
|
|
@C.foo.getter
|
|
def foo(self): return super().foo
|
|
self.assertRaises(TypeError, D)
|
|
class E(D):
|
|
@D.foo.setter
|
|
def foo(self, val): pass
|
|
self.assertFalse(E.foo.__isabstractmethod__)
|
|
|
|
def test_metaclass_abc(self):
|
|
# Metaclasses can be ABCs, too.
|
|
class A(metaclass=abc_ABCMeta):
|
|
@abc.abstractmethod
|
|
def x(self):
|
|
pass
|
|
self.assertEqual(A.__abstractmethods__, {"x"})
|
|
class meta(type, A):
|
|
def x(self):
|
|
return 1
|
|
class C(metaclass=meta):
|
|
pass
|
|
|
|
def test_registration_basics(self):
|
|
class A(metaclass=abc_ABCMeta):
|
|
pass
|
|
class B(object):
|
|
pass
|
|
b = B()
|
|
self.assertFalse(issubclass(B, A))
|
|
self.assertFalse(issubclass(B, (A,)))
|
|
self.assertNotIsInstance(b, A)
|
|
self.assertNotIsInstance(b, (A,))
|
|
B1 = A.register(B)
|
|
self.assertTrue(issubclass(B, A))
|
|
self.assertTrue(issubclass(B, (A,)))
|
|
self.assertIsInstance(b, A)
|
|
self.assertIsInstance(b, (A,))
|
|
self.assertIs(B1, B)
|
|
class C(B):
|
|
pass
|
|
c = C()
|
|
self.assertTrue(issubclass(C, A))
|
|
self.assertTrue(issubclass(C, (A,)))
|
|
self.assertIsInstance(c, A)
|
|
self.assertIsInstance(c, (A,))
|
|
|
|
def test_register_as_class_deco(self):
|
|
class A(metaclass=abc_ABCMeta):
|
|
pass
|
|
@A.register
|
|
class B(object):
|
|
pass
|
|
b = B()
|
|
self.assertTrue(issubclass(B, A))
|
|
self.assertTrue(issubclass(B, (A,)))
|
|
self.assertIsInstance(b, A)
|
|
self.assertIsInstance(b, (A,))
|
|
@A.register
|
|
class C(B):
|
|
pass
|
|
c = C()
|
|
self.assertTrue(issubclass(C, A))
|
|
self.assertTrue(issubclass(C, (A,)))
|
|
self.assertIsInstance(c, A)
|
|
self.assertIsInstance(c, (A,))
|
|
self.assertIs(C, A.register(C))
|
|
|
|
def test_isinstance_invalidation(self):
|
|
class A(metaclass=abc_ABCMeta):
|
|
pass
|
|
class B:
|
|
pass
|
|
b = B()
|
|
self.assertFalse(isinstance(b, A))
|
|
self.assertFalse(isinstance(b, (A,)))
|
|
token_old = abc_get_cache_token()
|
|
A.register(B)
|
|
token_new = abc_get_cache_token()
|
|
self.assertNotEqual(token_old, token_new)
|
|
self.assertTrue(isinstance(b, A))
|
|
self.assertTrue(isinstance(b, (A,)))
|
|
|
|
def test_registration_builtins(self):
|
|
class A(metaclass=abc_ABCMeta):
|
|
pass
|
|
A.register(int)
|
|
self.assertIsInstance(42, A)
|
|
self.assertIsInstance(42, (A,))
|
|
self.assertTrue(issubclass(int, A))
|
|
self.assertTrue(issubclass(int, (A,)))
|
|
class B(A):
|
|
pass
|
|
B.register(str)
|
|
class C(str): pass
|
|
self.assertIsInstance("", A)
|
|
self.assertIsInstance("", (A,))
|
|
self.assertTrue(issubclass(str, A))
|
|
self.assertTrue(issubclass(str, (A,)))
|
|
self.assertTrue(issubclass(C, A))
|
|
self.assertTrue(issubclass(C, (A,)))
|
|
|
|
def test_registration_edge_cases(self):
|
|
class A(metaclass=abc_ABCMeta):
|
|
pass
|
|
A.register(A) # should pass silently
|
|
class A1(A):
|
|
pass
|
|
self.assertRaises(RuntimeError, A1.register, A) # cycles not allowed
|
|
class B(object):
|
|
pass
|
|
A1.register(B) # ok
|
|
A1.register(B) # should pass silently
|
|
class C(A):
|
|
pass
|
|
A.register(C) # should pass silently
|
|
self.assertRaises(RuntimeError, C.register, A) # cycles not allowed
|
|
C.register(B) # ok
|
|
|
|
def test_register_non_class(self):
|
|
class A(metaclass=abc_ABCMeta):
|
|
pass
|
|
self.assertRaisesRegex(TypeError, "Can only register classes",
|
|
A.register, 4)
|
|
|
|
def test_registration_transitiveness(self):
|
|
class A(metaclass=abc_ABCMeta):
|
|
pass
|
|
self.assertTrue(issubclass(A, A))
|
|
self.assertTrue(issubclass(A, (A,)))
|
|
class B(metaclass=abc_ABCMeta):
|
|
pass
|
|
self.assertFalse(issubclass(A, B))
|
|
self.assertFalse(issubclass(A, (B,)))
|
|
self.assertFalse(issubclass(B, A))
|
|
self.assertFalse(issubclass(B, (A,)))
|
|
class C(metaclass=abc_ABCMeta):
|
|
pass
|
|
A.register(B)
|
|
class B1(B):
|
|
pass
|
|
self.assertTrue(issubclass(B1, A))
|
|
self.assertTrue(issubclass(B1, (A,)))
|
|
class C1(C):
|
|
pass
|
|
B1.register(C1)
|
|
self.assertFalse(issubclass(C, B))
|
|
self.assertFalse(issubclass(C, (B,)))
|
|
self.assertFalse(issubclass(C, B1))
|
|
self.assertFalse(issubclass(C, (B1,)))
|
|
self.assertTrue(issubclass(C1, A))
|
|
self.assertTrue(issubclass(C1, (A,)))
|
|
self.assertTrue(issubclass(C1, B))
|
|
self.assertTrue(issubclass(C1, (B,)))
|
|
self.assertTrue(issubclass(C1, B1))
|
|
self.assertTrue(issubclass(C1, (B1,)))
|
|
C1.register(int)
|
|
class MyInt(int):
|
|
pass
|
|
self.assertTrue(issubclass(MyInt, A))
|
|
self.assertTrue(issubclass(MyInt, (A,)))
|
|
self.assertIsInstance(42, A)
|
|
self.assertIsInstance(42, (A,))
|
|
|
|
def test_issubclass_bad_arguments(self):
|
|
class A(metaclass=abc_ABCMeta):
|
|
pass
|
|
|
|
with self.assertRaises(TypeError):
|
|
issubclass({}, A) # unhashable
|
|
|
|
with self.assertRaises(TypeError):
|
|
issubclass(42, A) # No __mro__
|
|
|
|
# Python version supports any iterable as __mro__.
|
|
# But it's implementation detail and don't emulate it in C version.
|
|
class C:
|
|
__mro__ = 42 # __mro__ is not tuple
|
|
|
|
with self.assertRaises(TypeError):
|
|
issubclass(C(), A)
|
|
|
|
# bpo-34441: Check that issubclass() doesn't crash on bogus
|
|
# classes.
|
|
bogus_subclasses = [
|
|
None,
|
|
lambda x: [],
|
|
lambda: 42,
|
|
lambda: [42],
|
|
]
|
|
|
|
for i, func in enumerate(bogus_subclasses):
|
|
class S(metaclass=abc_ABCMeta):
|
|
__subclasses__ = func
|
|
|
|
with self.subTest(i=i):
|
|
with self.assertRaises(TypeError):
|
|
issubclass(int, S)
|
|
|
|
# Also check that issubclass() propagates exceptions raised by
|
|
# __subclasses__.
|
|
exc_msg = "exception from __subclasses__"
|
|
|
|
def raise_exc():
|
|
raise Exception(exc_msg)
|
|
|
|
class S(metaclass=abc_ABCMeta):
|
|
__subclasses__ = raise_exc
|
|
|
|
with self.assertRaisesRegex(Exception, exc_msg):
|
|
issubclass(int, S)
|
|
|
|
def test_all_new_methods_are_called(self):
|
|
class A(metaclass=abc_ABCMeta):
|
|
pass
|
|
class B(object):
|
|
counter = 0
|
|
def __new__(cls):
|
|
B.counter += 1
|
|
return super().__new__(cls)
|
|
class C(A, B):
|
|
pass
|
|
self.assertEqual(B.counter, 0)
|
|
C()
|
|
self.assertEqual(B.counter, 1)
|
|
|
|
def test_ABC_has___slots__(self):
|
|
self.assertTrue(hasattr(abc.ABC, '__slots__'))
|
|
|
|
def test_tricky_new_works(self):
|
|
def with_metaclass(meta, *bases):
|
|
class metaclass(type):
|
|
def __new__(cls, name, this_bases, d):
|
|
return meta(name, bases, d)
|
|
return type.__new__(metaclass, 'temporary_class', (), {})
|
|
class A: ...
|
|
class B: ...
|
|
class C(with_metaclass(abc_ABCMeta, A, B)):
|
|
pass
|
|
self.assertEqual(C.__class__, abc_ABCMeta)
|
|
|
|
|
|
class TestABCWithInitSubclass(unittest.TestCase):
|
|
def test_works_with_init_subclass(self):
|
|
class abc_ABC(metaclass=abc_ABCMeta):
|
|
__slots__ = ()
|
|
saved_kwargs = {}
|
|
class ReceivesClassKwargs:
|
|
def __init_subclass__(cls, **kwargs):
|
|
super().__init_subclass__()
|
|
saved_kwargs.update(kwargs)
|
|
class Receiver(ReceivesClassKwargs, abc_ABC, x=1, y=2, z=3):
|
|
pass
|
|
self.assertEqual(saved_kwargs, dict(x=1, y=2, z=3))
|
|
return TestLegacyAPI, TestABC, TestABCWithInitSubclass
|
|
|
|
TestLegacyAPI_Py, TestABC_Py, TestABCWithInitSubclass_Py = test_factory(abc.ABCMeta,
|
|
abc.get_cache_token)
|
|
TestLegacyAPI_C, TestABC_C, TestABCWithInitSubclass_C = test_factory(_py_abc.ABCMeta,
|
|
_py_abc.get_cache_token)
|
|
|
|
if __name__ == "__main__":
|
|
unittest.main()
|