ActiveRecord::Errors is empty when the record is invalid

I'm running into an interesting problem where an ActiveRecord instance #valid? returns false, but #errors#full_messages is empty.

This is in one of my models. The code was run in ruby-debug sitting in one of my validation methods. (rdb:1) self.publisher_address.valid? false (rdb:1) self.publisher_address.errors.full_messages (rdb:1) a = (rdb:1) a.valid? false (rdb:1) a.errors.full_messages ["User can't be blank", "City can't be blank"...]

self.publisher_address is an unsaved Address object, created using So is a, which I just created. Both are invalid, yet a has error messages like it should but self.publisher_address doesn't. I can't figure out why.

(rdb:1) self.publisher_address #<Address id: nil, user_id: nil,...> (rdb:1) a #<Address id: nil, user_id: nil,...> (rdb:1) self.publisher_address.class Address(id: integer, user_id: integer,...) (rdb:1) a.class Address(id: integer, user_id: integer,...)

The #publisher_address method in this model is custom, not an association. I get the hash of the attributes and do return

self.publisher_address.errors is an AR::Errors object, but the actual errors are blank: (rdb:1) self.publisher_address.errors #<ActiveRecord::Errors:0x2cddf50 @base=#<Address id: nil, user_id: nil,...>, @errors=#<OrderedHash {}>>

Has anyone seen empty errors like this before?