diff options
Diffstat (limited to 'lib/sqlalchemy/ext/declarative/base.py')
| -rw-r--r-- | lib/sqlalchemy/ext/declarative/base.py | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/lib/sqlalchemy/ext/declarative/base.py b/lib/sqlalchemy/ext/declarative/base.py index 3beee3191..95f02ea96 100644 --- a/lib/sqlalchemy/ext/declarative/base.py +++ b/lib/sqlalchemy/ext/declarative/base.py @@ -568,8 +568,12 @@ class _DeferredMapperConfig(_MapperConfig): @classmethod def classes_for_base(cls, base_cls, sort=True): - classes_for_base = [m for m in cls._configs.values() - if issubclass(m.cls, base_cls)] + classes_for_base = [ + m for m, cls_ in + [(m, m.cls) for m in cls._configs.values()] + if cls_ is not None and issubclass(cls_, base_cls) + ] + if not sort: return classes_for_base |