1 files changed, 5 insertions, 5 deletions
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index 72f7df32c7..b751c9ad68 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -239,16 +239,16 @@ module ActiveRecord
       def inverse_of
         if has_inverse?
           @inverse_of ||= klass.reflect_on_association(options[:inverse_of])
-        else
-          nil
         end
       end
 
       def polymorphic_inverse_of(associated_class)
         if has_inverse?
-          associated_class.reflect_on_association(options[:inverse_of])
-        else
-          nil
+          if inverse_relationship = associated_class.reflect_on_association(options[:inverse_of])
+            inverse_relationship
+          else
+            raise InverseOfAssociationNotFoundError.new(self, associated_class)
+          end
         end
       end