diff options
Diffstat (limited to 'lib/sqlalchemy/attributes.py')
| -rw-r--r-- | lib/sqlalchemy/attributes.py | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/lib/sqlalchemy/attributes.py b/lib/sqlalchemy/attributes.py index bd5868baf..997b2c8f8 100644 --- a/lib/sqlalchemy/attributes.py +++ b/lib/sqlalchemy/attributes.py @@ -144,6 +144,8 @@ class ListElement(util.HistoryArraySet): # list that might be set on the object already try: list_ = obj.__dict__[key] + if list_ is data: + raise InvalidArgumentError("Creating a list element passing the object's list as an argument") if data is not None: for d in data: list_.append(d) @@ -435,8 +437,7 @@ class AttributeManager(object): elif not uselist: return PropHistory(obj, key, **kwargs) else: - list_ = obj.__dict__.get(key, None) - return self.create_list(obj, key, list_, **kwargs) + return self.create_list(obj, key, None, **kwargs) def register_attribute(self, class_, key, uselist, callable_=None, **kwargs): """registers an attribute's behavior at the class level. This attribute |