class ActiveRecord::PredicateBuilder::PolymorphicArrayValue

def queries
  return [ associated_table.join_foreign_key => values ] if values.empty?
  type_to_ids_mapping.map do |type, ids|
    query = {}
    query[associated_table.join_foreign_type] = type if type
    query[associated_table.join_foreign_key] = ids
    query
  end
end