1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
# Copyright 2007 Google, Inc. All Rights Reserved.
# Licensed to PSF under a Contributor Agreement.
"""Unit tests for abc.py."""
import unittest, weakref
from test import test_support
import abc
from inspect import isabstract
class TestABC(unittest.TestCase):
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):
@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
class D(C):
@property
def foo(self): return super(D, self).foo
self.assertEqual(D().foo, 3)
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_subclass_oldstyle_class(self):
class A:
__metaclass__ = abc.ABCMeta
class OldstyleClass:
pass
self.assertFalse(issubclass(OldstyleClass, A))
self.assertFalse(issubclass(A, OldstyleClass))
def test_isinstance_class(self):
class A:
__metaclass__ = abc.ABCMeta
class OldstyleClass:
pass
self.assertFalse(isinstance(OldstyleClass, A))
self.assertTrue(isinstance(OldstyleClass, type(OldstyleClass)))
self.assertFalse(isinstance(A, OldstyleClass))
# This raises a recursion depth error, but is low-priority:
# self.assertTrue(isinstance(A, abc.ABCMeta))
def test_registration_basics(self):
class A:
__metaclass__ = abc.ABCMeta
class B(object):
pass
b = B()
self.assertFalse(issubclass(B, A))
self.assertFalse(issubclass(B, (A,)))
self.assertNotIsInstance(b, A)
self.assertNotIsInstance(b, (A,))
A.register(B)
self.assertTrue(issubclass(B, A))
self.assertTrue(issubclass(B, (A,)))
self.assertIsInstance(b, A)
self.assertIsInstance(b, (A,))
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_isinstance_invalidation(self):
class A:
__metaclass__ = abc.ABCMeta
class B(object):
pass
b = B()
self.assertFalse(isinstance(b, A))
self.assertFalse(isinstance(b, (A,)))
A.register(B)
self.assertTrue(isinstance(b, A))
self.assertTrue(isinstance(b, (A,)))
def test_registration_builtins(self):
class A:
__metaclass__ = abc.ABCMeta
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(basestring)
self.assertIsInstance("", A)
self.assertIsInstance("", (A,))
self.assertTrue(issubclass(str, A))
self.assertTrue(issubclass(str, (A,)))
def test_registration_edge_cases(self):
class A:
__metaclass__ = abc.ABCMeta
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(object):
__metaclass__ = abc.ABCMeta
self.assertRaisesRegexp(TypeError, "Can only register classes",
A.register, 4)
def test_registration_transitiveness(self):
class A:
__metaclass__ = abc.ABCMeta
self.assertTrue(issubclass(A, A))
self.assertTrue(issubclass(A, (A,)))
class B:
__metaclass__ = abc.ABCMeta
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
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_all_new_methods_are_called(self):
class A:
__metaclass__ = abc.ABCMeta
class B(object):
counter = 0
def __new__(cls):
B.counter += 1
return super(B, cls).__new__(cls)
class C(A, B):
pass
self.assertEqual(B.counter, 0)
C()
self.assertEqual(B.counter, 1)
def test_cache_leak(self):
# See issue #2521.
class A(object):
__metaclass__ = abc.ABCMeta
@abc.abstractmethod
def f(self):
pass
class C(A):
def f(self):
A.f(self)
r = weakref.ref(C)
# Trigger cache.
C().f()
del C
test_support.gc_collect()
self.assertEqual(r(), None)
def test_main():
test_support.run_unittest(TestABC)
if __name__ == "__main__":
unittest.main()
|
