def testNestedPointers(self):
# Wrapped borrowed pointer vars do not modify in-place.
d = nested_fields.DD()
d.i = 123
a = nested_fields.AA()
a.dp = d
self.assertEqual(a.dp.i, 123)
a.dp.i = 321
self.assertEqual(a.dp.i, 123)
x = a.dp
self.assertIsNot(d, x)
self.assertEqual(d.i, x.i)
x.i = 321
self.assertEqual(a.dp.i, 123)
# Wrapped shared_ptr vars modify in-place.
a.ds = d
self.assertEqual(a.ds.i, 123)
a.ds.i = 456
self.assertEqual(a.ds.i, 456)
self.assertEqual(d.i, 456)
# Wrapped unique_ptr vars takes ownership (original var no longer valid)
# and do not modify in-place.
d = nested_fields.DD()
d.i = 321
a.du = d
with self.assertRaises(ValueError):
_ = d.i
self.assertEqual(a.du.i, 321)
a.du.i = 123
self.assertEqual(a.du.i, 321)
def testNestedStructFields(self):
a = nested_fields.AA()
a.b.c.i = 123
# The above change was "in-place".
self.assertEqual(a.b.c.i, 123)
c = a.b.c
c.i = 321
# |c| refers to the "in-place" attribute inside of |a|. Hence, the above
# change stays.
self.assertEqual(a.b.c.i, 321)
del c
# |a| is still alive and valid
self.assertEqual(a.b.c.i, 321)
c = a.b.c
del a
# |c| is still alive and valid
self.assertEqual(c.i, 321)
a = nested_fields.AA()
a.b.c.i = 123
c = a.b.c
with self.assertRaises(ValueError):
# Cannot give up |a| as |c| still is alive
nested_fields.ConsumeAA(a)
del c
# Since |c| is now gone, we can give up |a|
nested_fields.ConsumeAA(a)
a = nested_fields.AA()
a.b.c.i = 123
c = a.b.c
with self.assertRaises(ValueError):
# Cannot give up |c|
nested_fields.ConsumeCC(c)
del a
with self.assertRaises(ValueError):
# Cannot give up |c| even after |a| is gone; |c| holds a part of |a| and
# is unsafe to give up!
nested_fields.ConsumeCC(c)
def testNestedProperties(self):
# Properties and unproperties call functions which return the field values.
# We copy the returned values and do not modidy in-place (infact,
# "in-place" does not have any meaning for such cases.)
c = nested_fields.CC()
c.i = 123
a = nested_fields.AA()
a.SetC(c)
c = a.GetC()
c.i = 321
# Modifying the above |c| did not modify the field in |a|.
self.assertEqual(a.GetC().i, 123)
d = nested_fields.DD()
d.i = 123
b = a.b
b.d = d
b.d.i = 321
# Modifying |d| above did not modify the field in |b|.
self.assertEqual(b.d.i, 123)
def testNestedContainers(self): a = nested_fields.AA() a.v.append(123) # Above modification of field |v| in |a| did not happen in place. self.assertEqual(len(a.v), 0)