Method cssEscape

java/src/org/openqa/selenium/By.java:449–459

(String using)

    }

    private String cssEscape(String using) {
      using = CSS_ESCAPE.matcher(using).replaceAll("\\\\$1");
      // CSS only requires the leading-digit escape for ASCII 0-9; non-ASCII Unicode digits
      // (e.g. Arabic-Indic, fullwidth) are already valid identifier-start code points and must
      // be left untouched, or they collide with the escape for a different ASCII digit.
      char first = using.isEmpty() ? '\0' : using.charAt(0);
      if (first >= '0' && first <= '9') {
        using = "\\" + (30 + Integer.parseInt(using.substring(0, 1))) + " " + using.substring(1);
      }
      return using;
    }
  }
}