def testRefCountingOfReferredObjectAfterDeletingReferrer(self):
'''Deleting the object referring to other object should decrease the reference count of the referee.'''
d = Derived()
o = ObjectType()
refcount = getrefcount(o)
d.objectTypeField = o
self.assertEqual(getrefcount(o), refcount + 1)
del d
self.assertEqual(getrefcount(o), refcount)
def testRefCountingAccessingObjectTypeField(self):
'''Accessing a object type field should respect the reference counting rules.'''
d = Derived()
# attributing object to instance's field should increase its reference count
o1 = ObjectType()
refcount1 = getrefcount(o1)
d.objectTypeField = o1
self.assertEqual(d.objectTypeField, o1)
self.assertEqual(getrefcount(d.objectTypeField), refcount1 + 1)
# attributing a new object to instance's field should decrease the previous object's reference count
o2 = ObjectType()
refcount2 = getrefcount(o2)
d.objectTypeField = o2
self.assertEqual(d.objectTypeField, o2)
self.assertEqual(getrefcount(o1), refcount1)
self.assertEqual(getrefcount(d.objectTypeField), refcount2 + 1)
def testAccessingObjectTypeField(self):
'''Reads and writes a object type (in this case an 'ObjectType') field.'''
d = Derived()
# attribution
old_value = d.objectTypeField
new_value = ObjectType()
d.objectTypeField = new_value
self.assertEqual(d.objectTypeField, new_value)
self.assertNotEqual(d.objectTypeField, old_value)
# attribution with a convertible type
value = None
d.objectTypeField = value
self.assertEqual(d.objectTypeField, value)
# attribution with invalid type
self.assertRaises(TypeError, lambda : setattr(d, 'objectTypeField', 123))
def testAccessingObjectTypeField(self):
'''Reads and writes a object type (in this case an 'ObjectType') field.'''
d = Derived()
# attribution
old_value = d.objectTypeField
new_value = ObjectType()
d.objectTypeField = new_value
self.assertEqual(d.objectTypeField, new_value)
self.assertNotEqual(d.objectTypeField, old_value)
# attribution with a convertible type
value = None
d.objectTypeField = value
self.assertEqual(d.objectTypeField, value)
# attribution with invalid type
self.assertRaises(TypeError, lambda : setattr(d, 'objectTypeField', 123))
def testRefCountingOfReferredObjectAfterDeletingReferrer(self):
'''Deleting the object referring to other object should decrease the reference count of the referee.'''
d = Derived()
o = ObjectType()
refcount = getrefcount(o)
d.objectTypeField = o
self.assertEqual(getrefcount(o), refcount + 1)
del d
self.assertEqual(getrefcount(o), refcount)
def testRefCountingAccessingObjectTypeField(self):
'''Accessing a object type field should respect the reference counting rules.'''
d = Derived()
# attributing object to instance's field should increase its reference count
o1 = ObjectType()
refcount1 = getrefcount(o1)
d.objectTypeField = o1
self.assertEqual(d.objectTypeField, o1)
self.assertEqual(getrefcount(d.objectTypeField), refcount1 + 1)
# attributing a new object to instance's field should decrease the previous object's reference count
o2 = ObjectType()
refcount2 = getrefcount(o2)
d.objectTypeField = o2
self.assertEqual(d.objectTypeField, o2)
self.assertEqual(getrefcount(o1), refcount1)
self.assertEqual(getrefcount(d.objectTypeField), refcount2 + 1)
