# File lib/sass/selector/sequence.rb, line 79
      def contains_parent_ref?
        members.any? do |sseq_or_op|
          next false unless sseq_or_op.is_a?(SimpleSequence)
          next true if sseq_or_op.members.first.is_a?(Parent)
          sseq_or_op.members.any? do |sel|
            sel.is_a?(Pseudo) && sel.selector && sel.selector.contains_parent_ref?
          end
        end
      end