testmagicmethods.py 14 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468
  1. import unittest
  2. import sys
  3. from unittest.mock import Mock, MagicMock, _magics
  4. class TestMockingMagicMethods(unittest.TestCase):
  5. def test_deleting_magic_methods(self):
  6. mock = Mock()
  7. self.assertFalse(hasattr(mock, '__getitem__'))
  8. mock.__getitem__ = Mock()
  9. self.assertTrue(hasattr(mock, '__getitem__'))
  10. del mock.__getitem__
  11. self.assertFalse(hasattr(mock, '__getitem__'))
  12. def test_magicmock_del(self):
  13. mock = MagicMock()
  14. # before using getitem
  15. del mock.__getitem__
  16. self.assertRaises(TypeError, lambda: mock['foo'])
  17. mock = MagicMock()
  18. # this time use it first
  19. mock['foo']
  20. del mock.__getitem__
  21. self.assertRaises(TypeError, lambda: mock['foo'])
  22. def test_magic_method_wrapping(self):
  23. mock = Mock()
  24. def f(self, name):
  25. return self, 'fish'
  26. mock.__getitem__ = f
  27. self.assertIsNot(mock.__getitem__, f)
  28. self.assertEqual(mock['foo'], (mock, 'fish'))
  29. self.assertEqual(mock.__getitem__('foo'), (mock, 'fish'))
  30. mock.__getitem__ = mock
  31. self.assertIs(mock.__getitem__, mock)
  32. def test_magic_methods_isolated_between_mocks(self):
  33. mock1 = Mock()
  34. mock2 = Mock()
  35. mock1.__iter__ = Mock(return_value=iter([]))
  36. self.assertEqual(list(mock1), [])
  37. self.assertRaises(TypeError, lambda: list(mock2))
  38. def test_repr(self):
  39. mock = Mock()
  40. self.assertEqual(repr(mock), "<Mock id='%s'>" % id(mock))
  41. mock.__repr__ = lambda s: 'foo'
  42. self.assertEqual(repr(mock), 'foo')
  43. def test_str(self):
  44. mock = Mock()
  45. self.assertEqual(str(mock), object.__str__(mock))
  46. mock.__str__ = lambda s: 'foo'
  47. self.assertEqual(str(mock), 'foo')
  48. def test_dict_methods(self):
  49. mock = Mock()
  50. self.assertRaises(TypeError, lambda: mock['foo'])
  51. def _del():
  52. del mock['foo']
  53. def _set():
  54. mock['foo'] = 3
  55. self.assertRaises(TypeError, _del)
  56. self.assertRaises(TypeError, _set)
  57. _dict = {}
  58. def getitem(s, name):
  59. return _dict[name]
  60. def setitem(s, name, value):
  61. _dict[name] = value
  62. def delitem(s, name):
  63. del _dict[name]
  64. mock.__setitem__ = setitem
  65. mock.__getitem__ = getitem
  66. mock.__delitem__ = delitem
  67. self.assertRaises(KeyError, lambda: mock['foo'])
  68. mock['foo'] = 'bar'
  69. self.assertEqual(_dict, {'foo': 'bar'})
  70. self.assertEqual(mock['foo'], 'bar')
  71. del mock['foo']
  72. self.assertEqual(_dict, {})
  73. def test_numeric(self):
  74. original = mock = Mock()
  75. mock.value = 0
  76. self.assertRaises(TypeError, lambda: mock + 3)
  77. def add(self, other):
  78. mock.value += other
  79. return self
  80. mock.__add__ = add
  81. self.assertEqual(mock + 3, mock)
  82. self.assertEqual(mock.value, 3)
  83. del mock.__add__
  84. def iadd(mock):
  85. mock += 3
  86. self.assertRaises(TypeError, iadd, mock)
  87. mock.__iadd__ = add
  88. mock += 6
  89. self.assertEqual(mock, original)
  90. self.assertEqual(mock.value, 9)
  91. self.assertRaises(TypeError, lambda: 3 + mock)
  92. mock.__radd__ = add
  93. self.assertEqual(7 + mock, mock)
  94. self.assertEqual(mock.value, 16)
  95. def test_division(self):
  96. original = mock = Mock()
  97. mock.value = 32
  98. self.assertRaises(TypeError, lambda: mock / 2)
  99. def truediv(self, other):
  100. mock.value /= other
  101. return self
  102. mock.__truediv__ = truediv
  103. self.assertEqual(mock / 2, mock)
  104. self.assertEqual(mock.value, 16)
  105. del mock.__truediv__
  106. def itruediv(mock):
  107. mock /= 4
  108. self.assertRaises(TypeError, itruediv, mock)
  109. mock.__itruediv__ = truediv
  110. mock /= 8
  111. self.assertEqual(mock, original)
  112. self.assertEqual(mock.value, 2)
  113. self.assertRaises(TypeError, lambda: 8 / mock)
  114. mock.__rtruediv__ = truediv
  115. self.assertEqual(0.5 / mock, mock)
  116. self.assertEqual(mock.value, 4)
  117. def test_hash(self):
  118. mock = Mock()
  119. # test delegation
  120. self.assertEqual(hash(mock), Mock.__hash__(mock))
  121. def _hash(s):
  122. return 3
  123. mock.__hash__ = _hash
  124. self.assertEqual(hash(mock), 3)
  125. def test_nonzero(self):
  126. m = Mock()
  127. self.assertTrue(bool(m))
  128. m.__bool__ = lambda s: False
  129. self.assertFalse(bool(m))
  130. def test_comparison(self):
  131. mock = Mock()
  132. def comp(s, o):
  133. return True
  134. mock.__lt__ = mock.__gt__ = mock.__le__ = mock.__ge__ = comp
  135. self. assertTrue(mock < 3)
  136. self. assertTrue(mock > 3)
  137. self. assertTrue(mock <= 3)
  138. self. assertTrue(mock >= 3)
  139. self.assertRaises(TypeError, lambda: MagicMock() < object())
  140. self.assertRaises(TypeError, lambda: object() < MagicMock())
  141. self.assertRaises(TypeError, lambda: MagicMock() < MagicMock())
  142. self.assertRaises(TypeError, lambda: MagicMock() > object())
  143. self.assertRaises(TypeError, lambda: object() > MagicMock())
  144. self.assertRaises(TypeError, lambda: MagicMock() > MagicMock())
  145. self.assertRaises(TypeError, lambda: MagicMock() <= object())
  146. self.assertRaises(TypeError, lambda: object() <= MagicMock())
  147. self.assertRaises(TypeError, lambda: MagicMock() <= MagicMock())
  148. self.assertRaises(TypeError, lambda: MagicMock() >= object())
  149. self.assertRaises(TypeError, lambda: object() >= MagicMock())
  150. self.assertRaises(TypeError, lambda: MagicMock() >= MagicMock())
  151. def test_equality(self):
  152. for mock in Mock(), MagicMock():
  153. self.assertEqual(mock == mock, True)
  154. self.assertIsInstance(mock == mock, bool)
  155. self.assertEqual(mock != mock, False)
  156. self.assertIsInstance(mock != mock, bool)
  157. self.assertEqual(mock == object(), False)
  158. self.assertEqual(mock != object(), True)
  159. def eq(self, other):
  160. return other == 3
  161. mock.__eq__ = eq
  162. self.assertTrue(mock == 3)
  163. self.assertFalse(mock == 4)
  164. def ne(self, other):
  165. return other == 3
  166. mock.__ne__ = ne
  167. self.assertTrue(mock != 3)
  168. self.assertFalse(mock != 4)
  169. mock = MagicMock()
  170. mock.__eq__.return_value = True
  171. self.assertIsInstance(mock == 3, bool)
  172. self.assertEqual(mock == 3, True)
  173. mock.__ne__.return_value = False
  174. self.assertIsInstance(mock != 3, bool)
  175. self.assertEqual(mock != 3, False)
  176. def test_len_contains_iter(self):
  177. mock = Mock()
  178. self.assertRaises(TypeError, len, mock)
  179. self.assertRaises(TypeError, iter, mock)
  180. self.assertRaises(TypeError, lambda: 'foo' in mock)
  181. mock.__len__ = lambda s: 6
  182. self.assertEqual(len(mock), 6)
  183. mock.__contains__ = lambda s, o: o == 3
  184. self.assertIn(3, mock)
  185. self.assertNotIn(6, mock)
  186. mock.__iter__ = lambda s: iter('foobarbaz')
  187. self.assertEqual(list(mock), list('foobarbaz'))
  188. def test_magicmock(self):
  189. mock = MagicMock()
  190. mock.__iter__.return_value = iter([1, 2, 3])
  191. self.assertEqual(list(mock), [1, 2, 3])
  192. getattr(mock, '__bool__').return_value = False
  193. self.assertFalse(hasattr(mock, '__nonzero__'))
  194. self.assertFalse(bool(mock))
  195. for entry in _magics:
  196. self.assertTrue(hasattr(mock, entry))
  197. self.assertFalse(hasattr(mock, '__imaginary__'))
  198. def test_magic_mock_equality(self):
  199. mock = MagicMock()
  200. self.assertIsInstance(mock == object(), bool)
  201. self.assertIsInstance(mock != object(), bool)
  202. self.assertEqual(mock == object(), False)
  203. self.assertEqual(mock != object(), True)
  204. self.assertEqual(mock == mock, True)
  205. self.assertEqual(mock != mock, False)
  206. def test_magicmock_defaults(self):
  207. mock = MagicMock()
  208. self.assertEqual(int(mock), 1)
  209. self.assertEqual(complex(mock), 1j)
  210. self.assertEqual(float(mock), 1.0)
  211. self.assertNotIn(object(), mock)
  212. self.assertEqual(len(mock), 0)
  213. self.assertEqual(list(mock), [])
  214. self.assertEqual(hash(mock), object.__hash__(mock))
  215. self.assertEqual(str(mock), object.__str__(mock))
  216. self.assertTrue(bool(mock))
  217. # in Python 3 oct and hex use __index__
  218. # so these tests are for __index__ in py3k
  219. self.assertEqual(oct(mock), '0o1')
  220. self.assertEqual(hex(mock), '0x1')
  221. # how to test __sizeof__ ?
  222. def test_magic_methods_and_spec(self):
  223. class Iterable(object):
  224. def __iter__(self):
  225. pass
  226. mock = Mock(spec=Iterable)
  227. self.assertRaises(AttributeError, lambda: mock.__iter__)
  228. mock.__iter__ = Mock(return_value=iter([]))
  229. self.assertEqual(list(mock), [])
  230. class NonIterable(object):
  231. pass
  232. mock = Mock(spec=NonIterable)
  233. self.assertRaises(AttributeError, lambda: mock.__iter__)
  234. def set_int():
  235. mock.__int__ = Mock(return_value=iter([]))
  236. self.assertRaises(AttributeError, set_int)
  237. mock = MagicMock(spec=Iterable)
  238. self.assertEqual(list(mock), [])
  239. self.assertRaises(AttributeError, set_int)
  240. def test_magic_methods_and_spec_set(self):
  241. class Iterable(object):
  242. def __iter__(self):
  243. pass
  244. mock = Mock(spec_set=Iterable)
  245. self.assertRaises(AttributeError, lambda: mock.__iter__)
  246. mock.__iter__ = Mock(return_value=iter([]))
  247. self.assertEqual(list(mock), [])
  248. class NonIterable(object):
  249. pass
  250. mock = Mock(spec_set=NonIterable)
  251. self.assertRaises(AttributeError, lambda: mock.__iter__)
  252. def set_int():
  253. mock.__int__ = Mock(return_value=iter([]))
  254. self.assertRaises(AttributeError, set_int)
  255. mock = MagicMock(spec_set=Iterable)
  256. self.assertEqual(list(mock), [])
  257. self.assertRaises(AttributeError, set_int)
  258. def test_setting_unsupported_magic_method(self):
  259. mock = MagicMock()
  260. def set_setattr():
  261. mock.__setattr__ = lambda self, name: None
  262. self.assertRaisesRegex(AttributeError,
  263. "Attempting to set unsupported magic method '__setattr__'.",
  264. set_setattr
  265. )
  266. def test_attributes_and_return_value(self):
  267. mock = MagicMock()
  268. attr = mock.foo
  269. def _get_type(obj):
  270. # the type of every mock (or magicmock) is a custom subclass
  271. # so the real type is the second in the mro
  272. return type(obj).__mro__[1]
  273. self.assertEqual(_get_type(attr), MagicMock)
  274. returned = mock()
  275. self.assertEqual(_get_type(returned), MagicMock)
  276. def test_magic_methods_are_magic_mocks(self):
  277. mock = MagicMock()
  278. self.assertIsInstance(mock.__getitem__, MagicMock)
  279. mock[1][2].__getitem__.return_value = 3
  280. self.assertEqual(mock[1][2][3], 3)
  281. def test_magic_method_reset_mock(self):
  282. mock = MagicMock()
  283. str(mock)
  284. self.assertTrue(mock.__str__.called)
  285. mock.reset_mock()
  286. self.assertFalse(mock.__str__.called)
  287. def test_dir(self):
  288. # overriding the default implementation
  289. for mock in Mock(), MagicMock():
  290. def _dir(self):
  291. return ['foo']
  292. mock.__dir__ = _dir
  293. self.assertEqual(dir(mock), ['foo'])
  294. @unittest.skipIf('PyPy' in sys.version, "This fails differently on pypy")
  295. def test_bound_methods(self):
  296. m = Mock()
  297. # XXXX should this be an expected failure instead?
  298. # this seems like it should work, but is hard to do without introducing
  299. # other api inconsistencies. Failure message could be better though.
  300. m.__iter__ = [3].__iter__
  301. self.assertRaises(TypeError, iter, m)
  302. def test_magic_method_type(self):
  303. class Foo(MagicMock):
  304. pass
  305. foo = Foo()
  306. self.assertIsInstance(foo.__int__, Foo)
  307. def test_descriptor_from_class(self):
  308. m = MagicMock()
  309. type(m).__str__.return_value = 'foo'
  310. self.assertEqual(str(m), 'foo')
  311. def test_iterable_as_iter_return_value(self):
  312. m = MagicMock()
  313. m.__iter__.return_value = [1, 2, 3]
  314. self.assertEqual(list(m), [1, 2, 3])
  315. self.assertEqual(list(m), [1, 2, 3])
  316. m.__iter__.return_value = iter([4, 5, 6])
  317. self.assertEqual(list(m), [4, 5, 6])
  318. self.assertEqual(list(m), [])
  319. def test_matmul(self):
  320. m = MagicMock()
  321. self.assertIsInstance(m @ 1, MagicMock)
  322. m.__matmul__.return_value = 42
  323. m.__rmatmul__.return_value = 666
  324. m.__imatmul__.return_value = 24
  325. self.assertEqual(m @ 1, 42)
  326. self.assertEqual(1 @ m, 666)
  327. m @= 24
  328. self.assertEqual(m, 24)
  329. def test_divmod_and_rdivmod(self):
  330. m = MagicMock()
  331. self.assertIsInstance(divmod(5, m), MagicMock)
  332. m.__divmod__.return_value = (2, 1)
  333. self.assertEqual(divmod(m, 2), (2, 1))
  334. m = MagicMock()
  335. foo = divmod(2, m)
  336. self.assertIsInstance(foo, MagicMock)
  337. foo_direct = m.__divmod__(2)
  338. self.assertIsInstance(foo_direct, MagicMock)
  339. bar = divmod(m, 2)
  340. self.assertIsInstance(bar, MagicMock)
  341. bar_direct = m.__rdivmod__(2)
  342. self.assertIsInstance(bar_direct, MagicMock)
  343. # http://bugs.python.org/issue23310
  344. # Check if you can change behaviour of magic methods in MagicMock init
  345. def test_magic_in_initialization(self):
  346. m = MagicMock(**{'__str__.return_value': "12"})
  347. self.assertEqual(str(m), "12")
  348. def test_changing_magic_set_in_initialization(self):
  349. m = MagicMock(**{'__str__.return_value': "12"})
  350. m.__str__.return_value = "13"
  351. self.assertEqual(str(m), "13")
  352. m = MagicMock(**{'__str__.return_value': "12"})
  353. m.configure_mock(**{'__str__.return_value': "14"})
  354. self.assertEqual(str(m), "14")
  355. if __name__ == '__main__':
  356. unittest.main()