WC_Cart::get_cart_url PHP Method

    public function get_cart_url()
    {
        return wc_get_cart_url();
    }

 /**
  * Callback function that gets called when a customer cancels the payment directly
  */
 public static function onCancel()
 {
     self::debug(__CLASS__ . ': OnCancel - URL: http' . ($_SERVER['SERVER_PORT'] == 443 ? "s://" : "://") . $_SERVER["HTTP_HOST"] . $_SERVER["REQUEST_URI"]);
     $order = self::$wc_api->getOrderFromApiUrl();
     $order->add_order_note(__('PayPro - Customer cancelled payment. Redirected him back to his cart.'));
     self::debug(__CLASS__ . ': OnCancel - Payment cancelled by customer for order: ' . $order->id . '. Redirecting back to cart.');
     wp_safe_redirect(WC_Cart::get_cart_url());
     exit;
 }