- add workaround for sqlite memusage tests, so no longer need to count to 220/skip tests

- Fixed potential memory leak which could occur if an
arbitrary number of :class:`.sessionmaker` objects
were created.   The anonymous subclass created by
the sessionmaker, when dereferenced, would not be garbage
collected due to remaining class-level references from the
event package.  This issue also applies to any custom system
that made use of ad-hoc subclasses in conjunction with
an event dispatcher.  Also in 0.7.10. [ticket:2650]

1 files changed, 27 insertions, 1 deletions

diff --git a/test/base/test_events.py b/test/base/test_events.py
index eb58f5183..4efb30aba 100644
--- a/test/base/test_events.py
+++ b/test/base/test_events.py
@@ -2,8 +2,9 @@
 
 from sqlalchemy.testing import eq_, assert_raises, assert_raises_message, \
     is_, is_not_
-from sqlalchemy import event, exc, util
+from sqlalchemy import event, exc
 from sqlalchemy.testing import fixtures
+from sqlalchemy.testing.util import gc_collect
 
 class EventsTest(fixtures.TestBase):
     """Test class- and instance-level event registration."""
@@ -359,6 +360,31 @@ class CustomTargetsTest(fixtures.TestBase):
             listen, "event_one", self.Target
         )
 
+class SubclassGrowthTest(fixtures.TestBase):
+    """test that ad-hoc subclasses are garbage collected."""
+
+    def setUp(self):
+        class TargetEvents(event.Events):
+            def some_event(self, x, y):
+                pass
+
+        class Target(object):
+            dispatch = event.dispatcher(TargetEvents)
+
+        self.Target = Target
+
+    def test_subclass(self):
+        class SubTarget(self.Target):
+            pass
+
+        st = SubTarget()
+        st.dispatch.some_event(1, 2)
+        del st
+        del SubTarget
+        gc_collect()
+        eq_(self.Target.__subclasses__(), [])
+
+
 class ListenOverrideTest(fixtures.TestBase):
     """Test custom listen functions which change the listener function signature."""