Python code coverage for Lib/test/test_abc.py

#	count	content
1	n/a	# Copyright 2007 Google, Inc. All Rights Reserved.
2	n/a	# Licensed to PSF under a Contributor Agreement.
3	n/a
4	n/a	"""Unit tests for abc.py."""
5	n/a
6	n/a	import unittest
7	n/a	from test import support
8	n/a
9	n/a	import abc
10	n/a	from inspect import isabstract
11	n/a
12	n/a
13	n/a	class TestLegacyAPI(unittest.TestCase):
14	n/a
15	n/a	def test_abstractproperty_basics(self):
16	n/a	@abc.abstractproperty
17	n/a	def foo(self): pass
18	n/a	self.assertTrue(foo.__isabstractmethod__)
19	n/a	def bar(self): pass
20	n/a	self.assertFalse(hasattr(bar, "__isabstractmethod__"))
21	n/a
22	n/a	class C(metaclass=abc.ABCMeta):
23	n/a	@abc.abstractproperty
24	n/a	def foo(self): return 3
25	n/a	self.assertRaises(TypeError, C)
26	n/a	class D(C):
27	n/a	@property
28	n/a	def foo(self): return super().foo
29	n/a	self.assertEqual(D().foo, 3)
30	n/a	self.assertFalse(getattr(D.foo, "__isabstractmethod__", False))
31	n/a
32	n/a	def test_abstractclassmethod_basics(self):
33	n/a	@abc.abstractclassmethod
34	n/a	def foo(cls): pass
35	n/a	self.assertTrue(foo.__isabstractmethod__)
36	n/a	@classmethod
37	n/a	def bar(cls): pass
38	n/a	self.assertFalse(getattr(bar, "__isabstractmethod__", False))
39	n/a
40	n/a	class C(metaclass=abc.ABCMeta):
41	n/a	@abc.abstractclassmethod
42	n/a	def foo(cls): return cls.__name__
43	n/a	self.assertRaises(TypeError, C)
44	n/a	class D(C):
45	n/a	@classmethod
46	n/a	def foo(cls): return super().foo()
47	n/a	self.assertEqual(D.foo(), 'D')
48	n/a	self.assertEqual(D().foo(), 'D')
49	n/a
50	n/a	def test_abstractstaticmethod_basics(self):
51	n/a	@abc.abstractstaticmethod
52	n/a	def foo(): pass
53	n/a	self.assertTrue(foo.__isabstractmethod__)
54	n/a	@staticmethod
55	n/a	def bar(): pass
56	n/a	self.assertFalse(getattr(bar, "__isabstractmethod__", False))
57	n/a
58	n/a	class C(metaclass=abc.ABCMeta):
59	n/a	@abc.abstractstaticmethod
60	n/a	def foo(): return 3
61	n/a	self.assertRaises(TypeError, C)
62	n/a	class D(C):
63	n/a	@staticmethod
64	n/a	def foo(): return 4
65	n/a	self.assertEqual(D.foo(), 4)
66	n/a	self.assertEqual(D().foo(), 4)
67	n/a
68	n/a
69	n/a	class TestABC(unittest.TestCase):
70	n/a
71	n/a	def test_ABC_helper(self):
72	n/a	# create an ABC using the helper class and perform basic checks
73	n/a	class C(abc.ABC):
74	n/a	@classmethod
75	n/a	@abc.abstractmethod
76	n/a	def foo(cls): return cls.__name__
77	n/a	self.assertEqual(type(C), abc.ABCMeta)
78	n/a	self.assertRaises(TypeError, C)
79	n/a	class D(C):
80	n/a	@classmethod
81	n/a	def foo(cls): return super().foo()
82	n/a	self.assertEqual(D.foo(), 'D')
83	n/a
84	n/a	def test_abstractmethod_basics(self):
85	n/a	@abc.abstractmethod
86	n/a	def foo(self): pass
87	n/a	self.assertTrue(foo.__isabstractmethod__)
88	n/a	def bar(self): pass
89	n/a	self.assertFalse(hasattr(bar, "__isabstractmethod__"))
90	n/a
91	n/a	def test_abstractproperty_basics(self):
92	n/a	@property
93	n/a	@abc.abstractmethod
94	n/a	def foo(self): pass
95	n/a	self.assertTrue(foo.__isabstractmethod__)
96	n/a	def bar(self): pass
97	n/a	self.assertFalse(getattr(bar, "__isabstractmethod__", False))
98	n/a
99	n/a	class C(metaclass=abc.ABCMeta):
100	n/a	@property
101	n/a	@abc.abstractmethod
102	n/a	def foo(self): return 3
103	n/a	self.assertRaises(TypeError, C)
104	n/a	class D(C):
105	n/a	@C.foo.getter
106	n/a	def foo(self): return super().foo
107	n/a	self.assertEqual(D().foo, 3)
108	n/a
109	n/a	def test_abstractclassmethod_basics(self):
110	n/a	@classmethod
111	n/a	@abc.abstractmethod
112	n/a	def foo(cls): pass
113	n/a	self.assertTrue(foo.__isabstractmethod__)
114	n/a	@classmethod
115	n/a	def bar(cls): pass
116	n/a	self.assertFalse(getattr(bar, "__isabstractmethod__", False))
117	n/a
118	n/a	class C(metaclass=abc.ABCMeta):
119	n/a	@classmethod
120	n/a	@abc.abstractmethod
121	n/a	def foo(cls): return cls.__name__
122	n/a	self.assertRaises(TypeError, C)
123	n/a	class D(C):
124	n/a	@classmethod
125	n/a	def foo(cls): return super().foo()
126	n/a	self.assertEqual(D.foo(), 'D')
127	n/a	self.assertEqual(D().foo(), 'D')
128	n/a
129	n/a	def test_abstractstaticmethod_basics(self):
130	n/a	@staticmethod
131	n/a	@abc.abstractmethod
132	n/a	def foo(): pass
133	n/a	self.assertTrue(foo.__isabstractmethod__)
134	n/a	@staticmethod
135	n/a	def bar(): pass
136	n/a	self.assertFalse(getattr(bar, "__isabstractmethod__", False))
137	n/a
138	n/a	class C(metaclass=abc.ABCMeta):
139	n/a	@staticmethod
140	n/a	@abc.abstractmethod
141	n/a	def foo(): return 3
142	n/a	self.assertRaises(TypeError, C)
143	n/a	class D(C):
144	n/a	@staticmethod
145	n/a	def foo(): return 4
146	n/a	self.assertEqual(D.foo(), 4)
147	n/a	self.assertEqual(D().foo(), 4)
148	n/a
149	n/a	def test_abstractmethod_integration(self):
150	n/a	for abstractthing in [abc.abstractmethod, abc.abstractproperty,
151	n/a	abc.abstractclassmethod,
152	n/a	abc.abstractstaticmethod]:
153	n/a	class C(metaclass=abc.ABCMeta):
154	n/a	@abstractthing
155	n/a	def foo(self): pass # abstract
156	n/a	def bar(self): pass # concrete
157	n/a	self.assertEqual(C.__abstractmethods__, {"foo"})
158	n/a	self.assertRaises(TypeError, C) # because foo is abstract
159	n/a	self.assertTrue(isabstract(C))
160	n/a	class D(C):
161	n/a	def bar(self): pass # concrete override of concrete
162	n/a	self.assertEqual(D.__abstractmethods__, {"foo"})
163	n/a	self.assertRaises(TypeError, D) # because foo is still abstract
164	n/a	self.assertTrue(isabstract(D))
165	n/a	class E(D):
166	n/a	def foo(self): pass
167	n/a	self.assertEqual(E.__abstractmethods__, set())
168	n/a	E() # now foo is concrete, too
169	n/a	self.assertFalse(isabstract(E))
170	n/a	class F(E):
171	n/a	@abstractthing
172	n/a	def bar(self): pass # abstract override of concrete
173	n/a	self.assertEqual(F.__abstractmethods__, {"bar"})
174	n/a	self.assertRaises(TypeError, F) # because bar is abstract now
175	n/a	self.assertTrue(isabstract(F))
176	n/a
177	n/a	def test_descriptors_with_abstractmethod(self):
178	n/a	class C(metaclass=abc.ABCMeta):
179	n/a	@property
180	n/a	@abc.abstractmethod
181	n/a	def foo(self): return 3
182	n/a	@foo.setter
183	n/a	@abc.abstractmethod
184	n/a	def foo(self, val): pass
185	n/a	self.assertRaises(TypeError, C)
186	n/a	class D(C):
187	n/a	@C.foo.getter
188	n/a	def foo(self): return super().foo
189	n/a	self.assertRaises(TypeError, D)
190	n/a	class E(D):
191	n/a	@D.foo.setter
192	n/a	def foo(self, val): pass
193	n/a	self.assertEqual(E().foo, 3)
194	n/a	# check that the property's __isabstractmethod__ descriptor does the
195	n/a	# right thing when presented with a value that fails truth testing:
196	n/a	class NotBool(object):
197	n/a	def __bool__(self):
198	n/a	raise ValueError()
199	n/a	__len__ = __bool__
200	n/a	with self.assertRaises(ValueError):
201	n/a	class F(C):
202	n/a	def bar(self):
203	n/a	pass
204	n/a	bar.__isabstractmethod__ = NotBool()
205	n/a	foo = property(bar)
206	n/a
207	n/a
208	n/a	def test_customdescriptors_with_abstractmethod(self):
209	n/a	class Descriptor:
210	n/a	def __init__(self, fget, fset=None):
211	n/a	self._fget = fget
212	n/a	self._fset = fset
213	n/a	def getter(self, callable):
214	n/a	return Descriptor(callable, self._fget)
215	n/a	def setter(self, callable):
216	n/a	return Descriptor(self._fget, callable)
217	n/a	@property
218	n/a	def __isabstractmethod__(self):
219	n/a	return (getattr(self._fget, '__isabstractmethod__', False)
220	n/a	or getattr(self._fset, '__isabstractmethod__', False))
221	n/a	class C(metaclass=abc.ABCMeta):
222	n/a	@Descriptor
223	n/a	@abc.abstractmethod
224	n/a	def foo(self): return 3
225	n/a	@foo.setter
226	n/a	@abc.abstractmethod
227	n/a	def foo(self, val): pass
228	n/a	self.assertRaises(TypeError, C)
229	n/a	class D(C):
230	n/a	@C.foo.getter
231	n/a	def foo(self): return super().foo
232	n/a	self.assertRaises(TypeError, D)
233	n/a	class E(D):
234	n/a	@D.foo.setter
235	n/a	def foo(self, val): pass
236	n/a	self.assertFalse(E.foo.__isabstractmethod__)
237	n/a
238	n/a	def test_metaclass_abc(self):
239	n/a	# Metaclasses can be ABCs, too.
240	n/a	class A(metaclass=abc.ABCMeta):
241	n/a	@abc.abstractmethod
242	n/a	def x(self):
243	n/a	pass
244	n/a	self.assertEqual(A.__abstractmethods__, {"x"})
245	n/a	class meta(type, A):
246	n/a	def x(self):
247	n/a	return 1
248	n/a	class C(metaclass=meta):
249	n/a	pass
250	n/a
251	n/a	def test_registration_basics(self):
252	n/a	class A(metaclass=abc.ABCMeta):
253	n/a	pass
254	n/a	class B(object):
255	n/a	pass
256	n/a	b = B()
257	n/a	self.assertFalse(issubclass(B, A))
258	n/a	self.assertFalse(issubclass(B, (A,)))
259	n/a	self.assertNotIsInstance(b, A)
260	n/a	self.assertNotIsInstance(b, (A,))
261	n/a	B1 = A.register(B)
262	n/a	self.assertTrue(issubclass(B, A))
263	n/a	self.assertTrue(issubclass(B, (A,)))
264	n/a	self.assertIsInstance(b, A)
265	n/a	self.assertIsInstance(b, (A,))
266	n/a	self.assertIs(B1, B)
267	n/a	class C(B):
268	n/a	pass
269	n/a	c = C()
270	n/a	self.assertTrue(issubclass(C, A))
271	n/a	self.assertTrue(issubclass(C, (A,)))
272	n/a	self.assertIsInstance(c, A)
273	n/a	self.assertIsInstance(c, (A,))
274	n/a
275	n/a	def test_register_as_class_deco(self):
276	n/a	class A(metaclass=abc.ABCMeta):
277	n/a	pass
278	n/a	@A.register
279	n/a	class B(object):
280	n/a	pass
281	n/a	b = B()
282	n/a	self.assertTrue(issubclass(B, A))
283	n/a	self.assertTrue(issubclass(B, (A,)))
284	n/a	self.assertIsInstance(b, A)
285	n/a	self.assertIsInstance(b, (A,))
286	n/a	@A.register
287	n/a	class C(B):
288	n/a	pass
289	n/a	c = C()
290	n/a	self.assertTrue(issubclass(C, A))
291	n/a	self.assertTrue(issubclass(C, (A,)))
292	n/a	self.assertIsInstance(c, A)
293	n/a	self.assertIsInstance(c, (A,))
294	n/a	self.assertIs(C, A.register(C))
295	n/a
296	n/a	def test_isinstance_invalidation(self):
297	n/a	class A(metaclass=abc.ABCMeta):
298	n/a	pass
299	n/a	class B:
300	n/a	pass
301	n/a	b = B()
302	n/a	self.assertFalse(isinstance(b, A))
303	n/a	self.assertFalse(isinstance(b, (A,)))
304	n/a	token_old = abc.get_cache_token()
305	n/a	A.register(B)
306	n/a	token_new = abc.get_cache_token()
307	n/a	self.assertNotEqual(token_old, token_new)
308	n/a	self.assertTrue(isinstance(b, A))
309	n/a	self.assertTrue(isinstance(b, (A,)))
310	n/a
311	n/a	def test_registration_builtins(self):
312	n/a	class A(metaclass=abc.ABCMeta):
313	n/a	pass
314	n/a	A.register(int)
315	n/a	self.assertIsInstance(42, A)
316	n/a	self.assertIsInstance(42, (A,))
317	n/a	self.assertTrue(issubclass(int, A))
318	n/a	self.assertTrue(issubclass(int, (A,)))
319	n/a	class B(A):
320	n/a	pass
321	n/a	B.register(str)
322	n/a	class C(str): pass
323	n/a	self.assertIsInstance("", A)
324	n/a	self.assertIsInstance("", (A,))
325	n/a	self.assertTrue(issubclass(str, A))
326	n/a	self.assertTrue(issubclass(str, (A,)))
327	n/a	self.assertTrue(issubclass(C, A))
328	n/a	self.assertTrue(issubclass(C, (A,)))
329	n/a
330	n/a	def test_registration_edge_cases(self):
331	n/a	class A(metaclass=abc.ABCMeta):
332	n/a	pass
333	n/a	A.register(A) # should pass silently
334	n/a	class A1(A):
335	n/a	pass
336	n/a	self.assertRaises(RuntimeError, A1.register, A) # cycles not allowed
337	n/a	class B(object):
338	n/a	pass
339	n/a	A1.register(B) # ok
340	n/a	A1.register(B) # should pass silently
341	n/a	class C(A):
342	n/a	pass
343	n/a	A.register(C) # should pass silently
344	n/a	self.assertRaises(RuntimeError, C.register, A) # cycles not allowed
345	n/a	C.register(B) # ok
346	n/a
347	n/a	def test_register_non_class(self):
348	n/a	class A(metaclass=abc.ABCMeta):
349	n/a	pass
350	n/a	self.assertRaisesRegex(TypeError, "Can only register classes",
351	n/a	A.register, 4)
352	n/a
353	n/a	def test_registration_transitiveness(self):
354	n/a	class A(metaclass=abc.ABCMeta):
355	n/a	pass
356	n/a	self.assertTrue(issubclass(A, A))
357	n/a	self.assertTrue(issubclass(A, (A,)))
358	n/a	class B(metaclass=abc.ABCMeta):
359	n/a	pass
360	n/a	self.assertFalse(issubclass(A, B))
361	n/a	self.assertFalse(issubclass(A, (B,)))
362	n/a	self.assertFalse(issubclass(B, A))
363	n/a	self.assertFalse(issubclass(B, (A,)))
364	n/a	class C(metaclass=abc.ABCMeta):
365	n/a	pass
366	n/a	A.register(B)
367	n/a	class B1(B):
368	n/a	pass
369	n/a	self.assertTrue(issubclass(B1, A))
370	n/a	self.assertTrue(issubclass(B1, (A,)))
371	n/a	class C1(C):
372	n/a	pass
373	n/a	B1.register(C1)
374	n/a	self.assertFalse(issubclass(C, B))
375	n/a	self.assertFalse(issubclass(C, (B,)))
376	n/a	self.assertFalse(issubclass(C, B1))
377	n/a	self.assertFalse(issubclass(C, (B1,)))
378	n/a	self.assertTrue(issubclass(C1, A))
379	n/a	self.assertTrue(issubclass(C1, (A,)))
380	n/a	self.assertTrue(issubclass(C1, B))
381	n/a	self.assertTrue(issubclass(C1, (B,)))
382	n/a	self.assertTrue(issubclass(C1, B1))
383	n/a	self.assertTrue(issubclass(C1, (B1,)))
384	n/a	C1.register(int)
385	n/a	class MyInt(int):
386	n/a	pass
387	n/a	self.assertTrue(issubclass(MyInt, A))
388	n/a	self.assertTrue(issubclass(MyInt, (A,)))
389	n/a	self.assertIsInstance(42, A)
390	n/a	self.assertIsInstance(42, (A,))
391	n/a
392	n/a	def test_all_new_methods_are_called(self):
393	n/a	class A(metaclass=abc.ABCMeta):
394	n/a	pass
395	n/a	class B(object):
396	n/a	counter = 0
397	n/a	def __new__(cls):
398	n/a	B.counter += 1
399	n/a	return super().__new__(cls)
400	n/a	class C(A, B):
401	n/a	pass
402	n/a	self.assertEqual(B.counter, 0)
403	n/a	C()
404	n/a	self.assertEqual(B.counter, 1)
405	n/a
406	n/a
407	n/a	if __name__ == "__main__":
408	n/a	unittest.main()