import unittest
import sys
from unittest.mock import Mock, MagicMock, _magics
class TestMockingMagicMethods(unittest.TestCase):
def test_deleting_magic_methods(self):
mock = Mock()
self.assertFalse(hasattr(mock, '__getitem__'))
mock.__getitem__ = Mock()
self.assertTrue(hasattr(mock, '__getitem__'))
del mock.__getitem__
self.assertFalse(hasattr(mock, '__getitem__'))
def test_magicmock_del(self):
mock = MagicMock()
# before using getitem
del mock.__getitem__
self.assertRaises(TypeError, lambda: mock['foo'])
mock = MagicMock()
# this time use it first
mock['foo']
del mock.__getitem__
self.assertRaises(TypeError, lambda: mock['foo'])
def test_magic_method_wrapping(self):
mock = Mock()
def f(self, name):
return self, 'fish'
mock.__getitem__ = f
self.assertIsNot(mock.__getitem__, f)
self.assertEqual(mock['foo'], (mock, 'fish'))
self.assertEqual(mock.__getitem__('foo'), (mock, 'fish'))
mock.__getitem__ = mock
self.assertIs(mock.__getitem__, mock)
def test_magic_methods_isolated_between_mocks(self):
mock1 = Mock()
mock2 = Mock()
mock1.__iter__ = Mock(return_value=iter([]))
self.assertEqual(list(mock1), [])
self.assertRaises(TypeError, lambda: list(mock2))
def test_repr(self):
mock = Mock()
self.assertEqual(repr(mock), "<Mock id='%s'>" % id(mock))
mock.__repr__ = lambda s: 'foo'
self.assertEqual(repr(mock), 'foo')
def test_str(self):
mock = Mock()
self.assertEqual(str(mock), object.__str__(mock))
mock.__str__ = lambda s: 'foo'
self.assertEqual(str(mock), 'foo')
def test_dict_methods(self):
mock = Mock()
self.assertRaises(TypeError, lambda: mock['foo'])
def _del():
del mock['foo']
def _set():
mock['foo'] = 3
self.assertRaises(TypeError, _del)
self.assertRaises(TypeError, _set)
_dict = {}
def getitem(s, name):
return _dict[name]
def setitem(s, name, value):
_dict[name] = value
def delitem(s, name):
del _dict[name]
mock.__setitem__ = setitem
mock.__getitem__ = getitem
mock.__delitem__ = delitem
self.assertRaises(KeyError, lambda: mock['foo'])
mock['foo'] = 'bar'
self.assertEqual(_dict, {'foo': 'bar'})
self.assertEqual(mock['foo'], 'bar')
del mock['foo']
self.assertEqual(_dict, {})
def test_numeric(self):
original = mock = Mock()
mock.value = 0
self.assertRaises(TypeError, lambda: mock + 3)
def add(self, other):
mock.value += other
return self
mock.__add__ = add
self.assertEqual(mock + 3, mock)
self.assertEqual(mock.value, 3)
del mock.__add__
def iadd(mock):
mock += 3
self.assertRaises(TypeError, iadd, mock)
mock.__iadd__ = add
mock += 6
self.assertEqual(mock, original)
self.assertEqual(mock.value, 9)
self.assertRaises(TypeError, lambda: 3 + mock)
mock.__radd__ = add
self.assertEqual(7 + mock, mock)
self.assertEqual(mock.value, 16)
def test_division(self):
original = mock = Mock()
mock.value = 32
self.assertRaises(TypeError, lambda: mock / 2)
def truediv(self, other):
mock.value /= other
return self
mock.__truediv__ = truediv
self.assertEqual(mock / 2, mock)
self.assertEqual(mock.value, 16)
del mock.__truediv__
def itruediv(mock):
mock /= 4
self.assertRaises(TypeError, itruediv, mock)
mock.__itruediv__ = truediv
mock /= 8
self.assertEqual(mock, original)
self.assertEqual(mock.value, 2)
self.assertRaises(TypeError, lambda: 8 / mock)
mock.__rtruediv__ = truediv
self.assertEqual(0.5 / mock, mock)
self.assertEqual(mock.value, 4)
def test_hash(self):
mock = Mock()
# test delegation
self.assertEqual(hash(mock), Mock.__hash__(mock))
def _hash(s):
return 3
mock.__hash__ = _hash
self.assertEqual(hash(mock), 3)
def test_nonzero(self):
m = Mock()
self.assertTrue(bool(m))
m.__bool__ = lambda s: False
self.assertFalse(bool(m))
def test_comparison(self):
mock = Mock()
def comp(s, o):
return True
mock.__lt__ = mock.__gt__ = mock.__le__ = mock.__ge__ = comp
self. assertTrue(mock < 3)
self. assertTrue(mock > 3)
self. assertTrue(mock <= 3)
self. assertTrue(mock >= 3)
self.assertRaises(TypeError, lambda: MagicMock() < object())
self.assertRaises(TypeError, lambda: object() < MagicMock())
self.assertRaises(TypeError, lambda: MagicMock() < MagicMock())
self.assertRaises(TypeError, lambda: MagicMock() > object())
self.assertRaises(TypeError, lambda: object() > MagicMock())
self.assertRaises(TypeError, lambda: MagicMock() > MagicMock())
self.assertRaises(TypeError, lambda: MagicMock() <= object())
self.assertRaises(TypeError, lambda: object() <= MagicMock())
self.assertRaises(TypeError, lambda: MagicMock() <= MagicMock())
self.assertRaises(TypeError, lambda: MagicMock() >= object())
self.assertRaises(TypeError, lambda: object() >= MagicMock())
self.assertRaises(TypeError, lambda: MagicMock() >= MagicMock())
def test_equality(self):
for mock in Mock(), MagicMock():
self.assertEqual(mock == mock, True)
self.assertIsInstance(mock == mock, bool)
self.assertEqual(mock != mock, False)
self.assertIsInstance(mock != mock, bool)
self.assertEqual(mock == object(), False)
self.assertEqual(mock != object(), True)
def eq(self, other):
return other == 3
mock.__eq__ = eq
self.assertTrue(mock == 3)
self.assertFalse(mock == 4)
def ne(self, other):
return other == 3
mock.__ne__ = ne
self.assertTrue(mock != 3)
self.assertFalse(mock != 4)
mock = MagicMock()
mock.__eq__.return_value = True
self.assertIsInstance(mock == 3, bool)
self.assertEqual(mock == 3, True)
mock.__ne__.return_value = False
self.assertIsInstance(mock != 3, bool)
self.assertEqual(mock != 3, False)
def test_len_contains_iter(self):
mock = Mock()
self.assertRaises(TypeError, len, mock)
self.assertRaises(TypeError, iter, mock)
self.assertRaises(TypeError, lambda: 'foo' in mock)
mock.__len__ = lambda s: 6
self.assertEqual(len(mock), 6)
mock.__contains__ = lambda s, o: o == 3
self.assertIn(3, mock)
self.assertNotIn(6, mock)
mock.__iter__ = lambda s: iter('foobarbaz')
self.assertEqual(list(mock), list('foobarbaz'))
def test_magicmock(self):
mock = MagicMock()
mock.__iter__.return_value = iter([1, 2, 3])
self.assertEqual(list(mock), [1, 2, 3])
getattr(mock, '__bool__').return_value = False
self.assertFalse(hasattr(mock, '__nonzero__'))
self.assertFalse(bool(mock))
for entry in _magics:
self.assertTrue(hasattr(mock, entry))
self.assertFalse(hasattr(mock, '__imaginery__'))
def test_magic_mock_equality(self):
mock = MagicMock()
self.assertIsInstance(mock == object(), bool)
self.assertIsInstance(mock != object(), bool)
self.assertEqual(mock == object(), False)
self.assertEqual(mock != object(), True)
self.assertEqual(mock == mock, True)
self.assertEqual(mock != mock, False)
def test_magicmock_defaults(self):
mock = MagicMock()
self.assertEqual(int(mock), 1)
self.assertEqual(complex(mock), 1j)
self.assertEqual(float(mock), 1.0)
self.assertNotIn(object(), mock)
self.assertEqual(len(mock), 0)
self.assertEqual(list(mock), [])
self.assertEqual(hash(mock), object.__hash__(mock))
self.assertEqual(str(mock), object.__str__(mock))
self.assertTrue(bool(mock))
# in Python 3 oct and hex use __index__
# so these tests are for __index__ in py3k
self.assertEqual(oct(mock), '0o1')
self.assertEqual(hex(mock), '0x1')
# how to test __sizeof__ ?
def test_magic_methods_and_spec(self):
class Iterable(object):
def __iter__(self):
pass
mock = Mock(spec=Iterable)
self.assertRaises(AttributeError, lambda: mock.__iter__)
mock.__iter__ = Mock(return_value=iter([]))
self.assertEqual(list(mock), [])
class NonIterable(object):
pass
mock = Mock(spec=NonIterable)
self.assertRaises(AttributeError, lambda: mock.__iter__)
def set_int():
mock.__int__ = Mock(return_value=iter([]))
self.assertRaises(AttributeError, set_int)
mock = MagicMock(spec=Iterable)
self.assertEqual(list(mock), [])
self.assertRaises(AttributeError, set_int)
def test_magic_methods_and_spec_set(self):
class Iterable(object):
def __iter__(self):
pass
mock = Mock(spec_set=Iterable)
self.assertRaises(AttributeError, lambda: mock.__iter__)
mock.__iter__ = Mock(return_value=iter([]))
self.assertEqual(list(mock), [])
class NonIterable(object):
pass
mock = Mock(spec_set=NonIterable)
self.assertRaises(AttributeError, lambda: mock.__iter__)
def set_int():
mock.__int__ = Mock(return_value=iter([]))
self.assertRaises(AttributeError, set_int)
mock = MagicMock(spec_set=Iterable)
self.assertEqual(list(mock), [])
self.assertRaises(AttributeError, set_int)
def test_setting_unsupported_magic_method(self):
mock = MagicMock()
def set_setattr():
mock.__setattr__ = lambda self, name: None
self.assertRaisesRegex(AttributeError,
"Attempting to set unsupported magic method '__setattr__'.",
set_setattr
)
def test_attributes_and_return_value(self):
mock = MagicMock()
attr = mock.foo
def _get_type(obj):
# the type of every mock (or magicmock) is a custom subclass
# so the real type is the second in the mro
return type(obj).__mro__[1]
self.assertEqual(_get_type(attr), MagicMock)
returned = mock()
self.assertEqual(_get_type(returned), MagicMock)
def test_magic_methods_are_magic_mocks(self):
mock = MagicMock()
self.assertIsInstance(mock.__getitem__, MagicMock)
mock[1][2].__getitem__.return_value = 3
self.assertEqual(mock[1][2][3], 3)
def test_magic_method_reset_mock(self):
mock = MagicMock()
str(mock)
self.assertTrue(mock.__str__.called)
mock.reset_mock()
self.assertFalse(mock.__str__.called)
def test_dir(self):
# overriding the default implementation
for mock in Mock(), MagicMock():
def _dir(self):
return ['foo']
mock.__dir__ = _dir
self.assertEqual(dir(mock), ['foo'])
@unittest.skipIf('PyPy' in sys.version, "This fails differently on pypy")
def test_bound_methods(self):
m = Mock()
# XXXX should this be an expected failure instead?
# this seems like it should work, but is hard to do without introducing
# other api inconsistencies. Failure message could be better though.
m.__iter__ = [3].__iter__
self.assertRaises(TypeError, iter, m)
def test_magic_method_type(self):
class Foo(MagicMock):
pass
foo = Foo()
self.assertIsInstance(foo.__int__, Foo)
def test_descriptor_from_class(self):
m = MagicMock()
type(m).__str__.return_value = 'foo'
self.assertEqual(str(m), 'foo')
def test_iterable_as_iter_return_value(self):
m = MagicMock()
m.__iter__.return_value = [1, 2, 3]
self.assertEqual(list(m), [1, 2, 3])
self.assertEqual(list(m), [1, 2, 3])
m.__iter__.return_value = iter([4, 5, 6])
self.assertEqual(list(m), [4, 5, 6])
self.assertEqual(list(m), [])
def test_matmul(self):
m = MagicMock()
self.assertIsInstance(m @ 1, MagicMock)
m.__matmul__.return_value = 42
m.__rmatmul__.return_value = 666
m.__imatmul__.return_value = 24
self.assertEqual(m @ 1, 42)
self.assertEqual(1 @ m, 666)
m @= 24
self.assertEqual(m, 24)
def test_divmod_and_rdivmod(self):
m = MagicMock()
self.assertIsInstance(divmod(5, m), MagicMock)
m.__divmod__.return_value = (2, 1)
self.assertEqual(divmod(m, 2), (2, 1))
m = MagicMock()
foo = divmod(2, m)
self.assertIsInstance(foo, MagicMock)
foo_direct = m.__divmod__(2)
self.assertIsInstance(foo_direct, MagicMock)
bar = divmod(m, 2)
self.assertIsInstance(bar, MagicMock)
bar_direct = m.__rdivmod__(2)
self.assertIsInstance(bar_direct, MagicMock)
# http://bugs.python.org/issue23310
# Check if you can change behaviour of magic methods in MagicMock init
def test_magic_in_initialization(self):
m = MagicMock(**{'__str__.return_value': "12"})
self.assertEqual(str(m), "12")
def test_changing_magic_set_in_initialization(self):
m = MagicMock(**{'__str__.return_value': "12"})
m.__str__.return_value = "13"
self.assertEqual(str(m), "13")
m = MagicMock(**{'__str__.return_value': "12"})
m.configure_mock(**{'__str__.return_value': "14"})
self.assertEqual(str(m), "14")
if __name__ == '__main__':
unittest.main()