WC_Product::get_formatted_name PHP Method

    public function get_formatted_name()
    {
        if ($this->get_sku()) {
            $identifier = $this->get_sku();
        } else {
            $identifier = '#' . $this->get_id();
        }
        return sprintf('%s – %s', $identifier, $this->get_name());
    }

 /**
  * No stock notification email.
  *
  * @param WC_Product $product
  */
 public function no_stock($product)
 {
     $subject = sprintf('[%s] %s', $this->get_blogname(), __('Product out of stock', 'woocommerce'));
     $message = sprintf(__('%s is out of stock.', 'woocommerce'), html_entity_decode(strip_tags($product->get_formatted_name()), ENT_QUOTES, get_bloginfo('charset')));
     wp_mail(apply_filters('woocommerce_email_recipient_no_stock', get_option('woocommerce_stock_email_recipient'), $product), apply_filters('woocommerce_email_subject_no_stock', $subject, $product), apply_filters('woocommerce_email_content_no_stock', $message, $product), apply_filters('woocommerce_email_headers', '', 'no_stock', $product), apply_filters('woocommerce_email_attachments', array(), 'no_stock', $product));
 }