grouping_parentheses

# File activerecord/lib/arel/visitors/to_sql.rb, line 983
        def grouping_parentheses(o, collector, always_wrap_selects = true)
          if o.is_a?(Nodes::SelectStatement) && (always_wrap_selects || require_parentheses?(o))
            collector << "("
            visit o, collector
            collector << ")"
            collector
          else
            visit o, collector
          end
        end