attribute_match

# File actionpack/lib/action_controller/vendor/html-scanner/html/selector.rb, line 689
    def attribute_match(equality, value)
      regexp = value.is_a?(Regexp) ? value : Regexp.escape(value.to_s)
      case equality
        when "=" then
          # Match the attribute value in full
          Regexp.new("^#{regexp}$")
        when "~=" then
          # Match a space-separated word within the attribute value
          Regexp.new("(^|\s)#{regexp}($|\s)")
        when "^="
          # Match the beginning of the attribute value
          Regexp.new("^#{regexp}")
        when "$="
          # Match the end of the attribute value
          Regexp.new("#{regexp}$")
        when "*="
          # Match substring of the attribute value
          regexp.is_a?(Regexp) ? regexp : Regexp.new(regexp)
        when "|=" then
          # Match the first space-separated item of the attribute value
          Regexp.new("^#{regexp}($|\s)")
        else
          raise InvalidSelectorError, "Invalid operation/value" unless value.empty?
          # Match all attributes values (existence check)
          //
      end
    end