found an errant 2-tuple...

diff --git a/lib/sqlalchemy/orm/strategies.py b/lib/sqlalchemy/orm/strategies.py
index 17bb10ca22235b33bd2d5aed93ec1c311da49410..8016673ff59886ce8c2b3da96fd4e3b2a8b34c4b 100644 (file)
--- a/lib/sqlalchemy/orm/strategies.py
+++ b/lib/sqlalchemy/orm/strategies.py
@@ -83,7 +83,7 @@ class ColumnLoader(LoaderStrategy):
         # row fetcher used by inheritance.
         (hosted_mapper, needs_tables) = selectcontext.attributes.get(('polymorphic_fetch', mapper), (None, None))
         if hosted_mapper is None:
-            return (None, None)
+            return (None, None, None)
         
         if hosted_mapper.polymorphic_fetch == 'deferred':
             # 'deferred' polymorphic row fetcher, put a callable on the property.