invert_add_index

# File activerecord/lib/active_record/migration/command_recorder.rb, line 143
      def invert_add_index(args)
        table, columns, options = *args
        options ||= {}

        index_name = options[:name]
        options_hash = index_name ? { name: index_name } : { column: columns }

        [:remove_index, [table, options_hash]]
      end