code: function quoteXPathAttributeString(string) {
      "use strict";
      if (/"/g.test(string)) {
          return 'concat("' + string.toString().replace(/"/g, '", \'"\', "') + '")';
      } else {
          return '"' + string + '"';
      }
  }
docs: Prepares a string for xpath expression with the condition [text()=].
  
  @param  String  string
  @return String