process_node (HTML::WhiteListSanitizer)

    # File lib/action_controller/vendor/html-scanner/html/sanitizer.rb, line 138
        def process_node(node, result, options)
          result << case node
            when HTML::Tag
              if node.closing == :close
                options[:parent].shift
              else
                options[:parent].unshift node.name
              end

              process_attributes_for node, options

              options[:tags].include?(node.name) ? node : nil
            else
              bad_tags.include?(options[:parent].first) ? nil : node.to_s.gsub(/</, "&lt;")
          end
        end