objectstore unit tests run with postgres/sqlite

1 files changed, 5 insertions, 1 deletions

diff --git a/lib/sqlalchemy/sql.py b/lib/sqlalchemy/sql.py
index bcb02efa4..4ac3467b2 100644
--- a/lib/sqlalchemy/sql.py
+++ b/lib/sqlalchemy/sql.py
@@ -283,7 +283,11 @@ class CompareMixin(object):
         return self._compare('LIKE', other)
 
     def in_(self, *other):
-        if _is_literal(other[0]):
+        if len(other) == 0:
+            return self.__eq__(None)
+        elif len(other) == 1:
+            return self.__eq__(other[0])
+        elif _is_literal(other[0]):
             return self._compare('IN', CompoundClause(',', other))
         else:
             return self._compare('IN', union(*other))