Do not leak python references when using the gobject.property() helper.

Since this helper was storing plain references in a long-lived dict, the
refcount for the instances would never drop to zero, and so they would
never get finalized.

https://bugzilla.gnome.org/show_bug.cgi?id=644039

2 files changed, 25 insertions, 3 deletions

diff --git a/gobject/propertyhelper.py b/gobject/propertyhelper.py
index 745a13c4..9643c82b 100644
--- a/gobject/propertyhelper.py
+++ b/gobject/propertyhelper.py
@@ -144,7 +144,6 @@ class property(object):
 
         self.name = None
 
-        self._values = {}
         self._exc = None
 
     def __repr__(self):
@@ -270,10 +269,10 @@ class property(object):
     #
 
     def _default_setter(self, instance, value):
-        self._values[instance] = value
+        setattr(instance, '_property_helper_'+self.name, value)
 
     def _default_getter(self, instance):
-        return self._values.get(instance, self.default)
+        return getattr(instance, '_property_helper_'+self.name, self.default)
 
     def _readonly_setter(self, instance, value):
         self._exc = TypeError("%s property of %s is read-only" % (
diff --git a/tests/test_properties.py b/tests/test_properties.py
index 90db3ac6..14999031 100644
--- a/tests/test_properties.py
+++ b/tests/test_properties.py
@@ -401,5 +401,28 @@ class TestProperty(unittest.TestCase):
         gobject.property(type=gobject.TYPE_FLOAT, minimum=-1)
         gobject.property(type=gobject.TYPE_DOUBLE, minimum=-1)
 
+    # Bug 644039
+    def testReferenceCount(self):
+        # We can check directly if an object gets finalized, so we will
+        # observe it indirectly through the refcount of a member object.
+
+        # We create our dummy object and store its current refcount
+        o = object()
+        rc = sys.getrefcount(o)
+
+        # We add our object as a member to our newly created object we
+        # want to observe. Its refcount is increased by one.
+        t = PropertyObject(normal="test")
+        t.o = o
+        self.assertEquals(sys.getrefcount(o), rc + 1)
+
+        # Now we want to ensure we do not leak any references to our
+        # object with properties. If no ref is leaked, then when deleting
+        # the local reference to this object, its reference count shoud
+        # drop to zero, and our dummy object should loose one reference.
+        del t
+        self.assertEquals(sys.getrefcount(o), rc)
+
+
 if __name__ == '__main__':
     unittest.main()