Broken circular reference in async execution

If a connection is destroyed before an async operation is completed, the
`async_cursor` member creates a reference loop, leaving the connection and
the cursor alive. `async_cursor` is now a weak reference.

1 files changed, 12 insertions, 0 deletions

diff --git a/tests/test_async.py b/tests/test_async.py
index 96d7a2c..d4854fc 100755
--- a/tests/test_async.py
+++ b/tests/test_async.py
@@ -415,6 +415,18 @@ class AsyncTests(unittest.TestCase):
         self.assertEqual("CREATE TABLE", cur.statusmessage)
         self.assert_(self.conn.notices)
 
+    def test_async_cursor_gone(self):
+        cur = self.conn.cursor()
+        cur.execute("select 42;");
+        del cur
+        self.assertRaises(psycopg2.InterfaceError, self.wait, self.conn)
+
+        # The connection is still usable
+        cur = self.conn.cursor()
+        cur.execute("select 42;");
+        self.wait(self.conn)
+        self.assertEqual(cur.fetchone(), (42,))
+
 
 def test_suite():
     return unittest.TestLoader().loadTestsFromName(__name__)