Ticket #10784: 10784-admin-list_editable-ordering-validation.diff

django/contrib/admin/validation.py

@@ -91 +91 @@
                 raise ImproperlyConfigured("'%s.list_editable[%d]' refers to a "
                     "field, '%s', which isn't editable through the admin."
                     % (cls.__name__, idx, field_name))
+            if not field.unique and (field_name in (cls.ordering or opts.ordering or ())):
+                raise ImproperlyConfigured("'%s.list_editable[%d]' refers to a "
+                    "non-unique field, '%s', which controls the ordering of "
+                    "items in the admin."
+                    % (cls.__name__, idx, field_name))
 
     # search_fields = ()
     if hasattr(cls, 'search_fields'):