class SafeMarkup

class SafeMarkup {
    
    /**
     * Checks if a string is safe to output.
     *
     * @param string|\Drupal\Component\Render\MarkupInterface $string
     *   The content to be checked.
     * @param string $strategy
     *   (optional) This value is ignored.
     *
     * @return bool
     *   TRUE if the string has been marked secure, FALSE otherwise.
     *
     * @deprecated in drupal:8.0.0 and is removed from drupal:9.0.0.
     *   Instead, you should just check if a variable is an instance of
     *   \Drupal\Component\Render\MarkupInterface.
     *
     * @see https://www.drupal.org/node/2549395
     */
    public static function isSafe($string, $strategy = 'html') {
        @trigger_error('SafeMarkup::isSafe() is scheduled for removal in Drupal 9.0.0. Instead, you should just check if a variable is an instance of \\Drupal\\Component\\Render\\MarkupInterface. See https://www.drupal.org/node/2549395.', E_USER_DEPRECATED);
        return $string instanceof MarkupInterface;
    }
    
    /**
     * Encodes special characters in a plain-text string for display as HTML.
     *
     * Also validates strings as UTF-8. All processed strings are also
     * automatically flagged as safe markup strings for rendering.
     *
     * @param string $text
     *   The text to be checked or processed.
     *
     * @return \Drupal\Component\Render\HtmlEscapedText
     *   An HtmlEscapedText object that escapes when rendered to string.
     *
     * @deprecated Will be removed before Drupal 9.0.0. Rely on Twig's
     *   auto-escaping feature, or use the @link theme_render #plain_text @endlink
     *   key when constructing a render array that contains plain text in order to
     *   use the renderer's auto-escaping feature. If neither of these are
     *   possible, \Drupal\Component\Utility\Html::escape() can be used in places
     *   where explicit escaping is needed.
     *
     * @see https://www.drupal.org/node/2549395
     * @see drupal_validate_utf8()
     */
    public static function checkPlain($text) {
        @trigger_error('SafeMarkup::checkPlain() is scheduled for removal in Drupal 9.0.0. Rely on Twig\'s auto-escaping feature, or use the @link theme_render #plain_text @endlink key when constructing a render array that contains plain text in order to use the renderer\'s auto-escaping feature. If neither of these are possible, \\Drupal\\Component\\Utility\\Html::escape() can be used in places where explicit escaping is needed. See https://www.drupal.org/node/2549395.', E_USER_DEPRECATED);
        return new HtmlEscapedText($text);
    }
    
    /**
     * Formats a string for HTML display by replacing variable placeholders.
     *
     * @param string $string
     *   A string containing placeholders. The string itself will not be escaped,
     *   any unsafe content must be in $args and inserted via placeholders.
     * @param array $args
     *   An array with placeholder replacements, keyed by placeholder. See
     *   \Drupal\Component\Render\FormattableMarkup::placeholderFormat() for
     *   additional information about placeholders.
     *
     * @return string|\Drupal\Component\Render\MarkupInterface
     *   The formatted string, which is an instance of MarkupInterface unless
     *   sanitization of an unsafe argument was suppressed (see above).
     *
     * @see \Drupal\Component\Render\FormattableMarkup::placeholderFormat()
     * @see \Drupal\Component\Render\FormattableMarkup
     *
     * @deprecated in drupal:8.0.0 and is removed from drupal:9.0.0.
     *   Use \Drupal\Component\Render\FormattableMarkup.
     *
     * @see https://www.drupal.org/node/2549395
     */
    public static function format($string, array $args) {
        @trigger_error('SafeMarkup::format() is scheduled for removal in Drupal 9.0.0. Use \\Drupal\\Component\\Render\\FormattableMarkup. See https://www.drupal.org/node/2549395.', E_USER_DEPRECATED);
        return new FormattableMarkup($string, $args);
    }

}