added teardown_instance() to complement setup_instance().

Based on the instance/class agnostic behavior of ClassManager, this might be the best we can
do regarding [ticket:860]

1 files changed, 6 insertions, 0 deletions

diff --git a/lib/sqlalchemy/orm/attributes.py b/lib/sqlalchemy/orm/attributes.py
index 2b2760208..5c242aa7e 100644
--- a/lib/sqlalchemy/orm/attributes.py
+++ b/lib/sqlalchemy/orm/attributes.py
@@ -1269,6 +1269,9 @@ class ClassManager(dict):
 
     def setup_instance(self, instance, state=None):
         setattr(instance, self.STATE_ATTR, state or self.instance_state_factory(instance, self))
+    
+    def teardown_instance(self, instance):
+        delattr(instance, self.STATE_ATTR)
         
     def _new_state_if_none(self, instance):
         """Install a default InstanceState if none is present.
@@ -1381,6 +1384,9 @@ class _ClassInstrumentationAdapter(ClassManager):
         state.dict = self._adapted.get_instance_dict(self.class_, instance)
         return state
 
+    def teardown_instance(self, instance):
+        self._adapted.remove_state(self.class_, instance)
+
     def state_of(self, instance):
         if hasattr(self._adapted, 'state_of'):
             return self._adapted.state_of(self.class_, instance)