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
python类abstractmethod()的实例源码
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_abstractmethod_integration(self):
for abstractthing in [abc.abstractmethod, abc.abstractproperty]:
class C:
__metaclass__ = abc.ABCMeta
@abstractthing
def foo(self): pass # abstract
def bar(self): pass # concrete
self.assertEqual(C.__abstractmethods__, set(["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__, set(["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__, set(["bar"]))
self.assertRaises(TypeError, F) # because bar is abstract now
self.assertTrue(isabstract(F))
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_abstractmethod_integration(self):
for abstractthing in [abc.abstractmethod, abc.abstractproperty]:
class C:
__metaclass__ = abc.ABCMeta
@abstractthing
def foo(self): pass # abstract
def bar(self): pass # concrete
self.assertEqual(C.__abstractmethods__, set(["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__, set(["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__, set(["bar"]))
self.assertRaises(TypeError, F) # because bar is abstract now
self.assertTrue(isabstract(F))
def abstractmethod(func):
return func
# def abstractproperty():
# return None
def _set_info(self):
'''save useful info about table/datasource'''
pass
#@abc.abstractmethod
#def get_connection(self):
# '''get con[nection] for database handles'''
# pass
def abstractmethod(self):
return self
### ONE-TRICK PONIES ###
#class Iterable(metaclass=ABCMeta):
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_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 __nonzero__(self):
raise ValueError()
__len__ = __nonzero__
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 __iter__(self):
yield('Feed', dict(self._stree.snode_root))
# @abc.abstractmethod
# def create(self, **kwargs):
# """Create a new tree
#
# """
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_abstractmethod_integration(self):
for abstractthing in [abc.abstractmethod, abc.abstractproperty]:
class C:
__metaclass__ = abc.ABCMeta
@abstractthing
def foo(self): pass # abstract
def bar(self): pass # concrete
self.assertEqual(C.__abstractmethods__, set(["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__, set(["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__, set(["bar"]))
self.assertRaises(TypeError, F) # because bar is abstract now
self.assertTrue(isabstract(F))
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_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
