diff options
Diffstat (limited to 'lib/sqlalchemy/orm/evaluator.py')
| -rw-r--r-- | lib/sqlalchemy/orm/evaluator.py | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/lib/sqlalchemy/orm/evaluator.py b/lib/sqlalchemy/orm/evaluator.py index e1dd96068..ca26c9ca4 100644 --- a/lib/sqlalchemy/orm/evaluator.py +++ b/lib/sqlalchemy/orm/evaluator.py @@ -25,6 +25,9 @@ _notimplemented_ops = set(getattr(operators, op) class EvaluatorCompiler(object): + def __init__(self, target_cls=None): + self.target_cls = target_cls + def process(self, clause): meth = getattr(self, "visit_%s" % clause.__visit_name__, None) if not meth: @@ -46,10 +49,17 @@ class EvaluatorCompiler(object): def visit_column(self, clause): if 'parentmapper' in clause._annotations: - key = clause._annotations['parentmapper'].\ - _columntoproperty[clause].key + parentmapper = clause._annotations['parentmapper'] + if self.target_cls and not issubclass( + self.target_cls, parentmapper.class_): + raise UnevaluatableError( + "Can't evaluate criteria against alternate class %s" % + parentmapper.class_ + ) + key = parentmapper._columntoproperty[clause].key else: key = clause.key + get_corresponding_attr = operator.attrgetter(key) return lambda obj: get_corresponding_attr(obj) |