diff options
| -rw-r--r-- | Lib/test/test_weakref.py | 105 | ||||
| -rw-r--r-- | Misc/NEWS | 2 | ||||
| -rw-r--r-- | Objects/weakrefobject.c | 10 |
3 files changed, 93 insertions, 24 deletions
diff --git a/Lib/test/test_weakref.py b/Lib/test/test_weakref.py index 74b9a87..92a4713 100644 --- a/Lib/test/test_weakref.py +++ b/Lib/test/test_weakref.py @@ -32,6 +32,27 @@ def create_bound_method(): return C().method +class Object: + def __init__(self, arg): + self.arg = arg + def __repr__(self): + return "<Object %r>" % self.arg + def __eq__(self, other): + if isinstance(other, Object): + return self.arg == other.arg + return NotImplemented + def __lt__(self, other): + if isinstance(other, Object): + return self.arg < other.arg + return NotImplemented + def __hash__(self): + return hash(self.arg) + +class RefCycle: + def __init__(self): + self.cycle = self + + class TestBase(unittest.TestCase): def setUp(self): @@ -692,6 +713,69 @@ class ReferencesTestCase(TestBase): self.assertEqual(a(), None) self.assertEqual(l, [a]) + def test_equality(self): + # Alive weakrefs defer equality testing to their underlying object. + x = Object(1) + y = Object(1) + z = Object(2) + a = weakref.ref(x) + b = weakref.ref(y) + c = weakref.ref(z) + d = weakref.ref(x) + # Note how we directly test the operators here, to stress both + # __eq__ and __ne__. + self.assertTrue(a == b) + self.assertFalse(a != b) + self.assertFalse(a == c) + self.assertTrue(a != c) + self.assertTrue(a == d) + self.assertFalse(a != d) + del x, y, z + gc.collect() + for r in a, b, c: + # Sanity check + self.assertIs(r(), None) + # Dead weakrefs compare by identity: whether `a` and `d` are the + # same weakref object is an implementation detail, since they pointed + # to the same original object and didn't have a callback. + # (see issue #16453). + self.assertFalse(a == b) + self.assertTrue(a != b) + self.assertFalse(a == c) + self.assertTrue(a != c) + self.assertEqual(a == d, a is d) + self.assertEqual(a != d, a is not d) + + def test_ordering(self): + # weakrefs cannot be ordered, even if the underlying objects can. + ops = [operator.lt, operator.gt, operator.le, operator.ge] + x = Object(1) + y = Object(1) + a = weakref.ref(x) + b = weakref.ref(y) + for op in ops: + self.assertRaises(TypeError, op, a, b) + # Same when dead. + del x, y + gc.collect() + for op in ops: + self.assertRaises(TypeError, op, a, b) + + def test_hashing(self): + # Alive weakrefs hash the same as the underlying object + x = Object(42) + y = Object(42) + a = weakref.ref(x) + b = weakref.ref(y) + self.assertEqual(hash(a), hash(42)) + del x, y + gc.collect() + # Dead weakrefs: + # - retain their hash is they were hashed when alive; + # - otherwise, cannot be hashed. + self.assertEqual(hash(a), hash(42)) + self.assertRaises(TypeError, hash, b) + class SubclassableWeakrefTestCase(TestBase): @@ -796,27 +880,6 @@ class SubclassableWeakrefTestCase(TestBase): self.assertEqual(self.cbcalled, 0) -class Object: - def __init__(self, arg): - self.arg = arg - def __repr__(self): - return "<Object %r>" % self.arg - def __eq__(self, other): - if isinstance(other, Object): - return self.arg == other.arg - return NotImplemented - def __lt__(self, other): - if isinstance(other, Object): - return self.arg < other.arg - return NotImplemented - def __hash__(self): - return hash(self.arg) - -class RefCycle: - def __init__(self): - self.cycle = self - - class MappingTestCase(TestBase): COUNT = 10 @@ -10,6 +10,8 @@ What's New in Python 3.4.0 Alpha 1? Core and Builtins ----------------- +- Issue #16453: Fix equality testing of dead weakref objects. + - Issue #9535: Fix pending signals that have been received but not yet handled by Python to not persist after os.fork() in the child process. diff --git a/Objects/weakrefobject.c b/Objects/weakrefobject.c index e07adb2..d3a4dd5 100644 --- a/Objects/weakrefobject.c +++ b/Objects/weakrefobject.c @@ -198,9 +198,13 @@ weakref_richcompare(PyWeakReference* self, PyWeakReference* other, int op) } if (PyWeakref_GET_OBJECT(self) == Py_None || PyWeakref_GET_OBJECT(other) == Py_None) { - PyObject *res = self==other ? Py_True : Py_False; - Py_INCREF(res); - return res; + int res = (self == other); + if (op == Py_NE) + res = !res; + if (res) + Py_RETURN_TRUE; + else + Py_RETURN_FALSE; } return PyObject_RichCompare(PyWeakref_GET_OBJECT(self), PyWeakref_GET_OBJECT(other), op); |