dependency sort thing getting out of hand

diff --git a/lib/sqlalchemy/attributes.py b/lib/sqlalchemy/attributes.py
index 959a39ad949e4556e2ae4b3a113ea26d9534330f..a12b57accb72580cca360c16a8995aee5626d2a9 100644 (file)
--- a/lib/sqlalchemy/attributes.py
+++ b/lib/sqlalchemy/attributes.py
@@ -57,6 +57,8 @@ class PropHistory(object):
     def setattr_clean(self, value):
         self.obj.__dict__[self.key] = value
     def setattr(self, value):
+        if isinstance(value, list):
+            raise ("assigning a list to scalar property '%s' on '%s' instance %d" % (self.key, self.obj.__class__.__name__, id(self.obj)))
         self.orig = self.obj.__dict__.get(self.key, None)
         self.obj.__dict__[self.key] = value
     def delattr(self):