sanitize

# File activerecord/lib/active_record/associations/join_helper.rb, line 44
      def sanitize(conditions, table)
        conditions = conditions.map do |condition|
          condition = active_record.send(:sanitize_sql, interpolate(condition), table.table_alias || table.name)
          condition = Arel.sql(condition) unless condition.is_a?(Arel::Node)
          condition
        end

        conditions.length == 1 ? conditions.first : Arel::Nodes::And.new(conditions)
      end