diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/test/test_weakref.py | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/Lib/test/test_weakref.py b/Lib/test/test_weakref.py index dc6bf77..cdd26c7 100644 --- a/Lib/test/test_weakref.py +++ b/Lib/test/test_weakref.py @@ -781,6 +781,27 @@ class ReferencesTestCase(TestBase): self.assertEqual(hash(a), hash(42)) self.assertRaises(TypeError, hash, b) + def test_trashcan_16602(self): + # Issue #16602: when a weakref's target was part of a long + # deallocation chain, the trashcan mechanism could delay clearing + # of the weakref and make the target object visible from outside + # code even though its refcount had dropped to 0. A crash ensued. + class C: + def __init__(self, parent): + if not parent: + return + wself = weakref.ref(self) + def cb(wparent): + o = wself() + self.wparent = weakref.ref(parent, cb) + + d = weakref.WeakKeyDictionary() + root = c = C(None) + for n in range(100): + d[c] = c = C(c) + del root + gc.collect() + class SubclassableWeakrefTestCase(TestBase): |