class ActiveRecord::PredicateBuilder::AssociationQueryValue

def ids
  case value
  when Relation
    relation = value
    relation = relation.select(primary_key) if select_clause?
    relation = relation.where(primary_type => polymorphic_name) if polymorphic_clause?
    relation
  when Array
    value.map { |v| convert_to_id(v) }
  else
    [convert_to_id(value)]
  end
end