# 商品詳細
Product/detail.twig:
    - [onRenderProductDetail, NORMAL]

    /**
     * 商品詳細ページにエラーメッセージを表示する.
     *
     * @param TemplateEvent $event
     */
    public function onRenderProductDetail(TemplateEvent $event)
    {
        $app = $this->app;
        $source = $event->getSource();

        $search = '<!-- ▼item_detail▼ -->';
        $replace = '{% for error in app.session.flashbag.get("eccube.front.request.error")  %}
                        <div id="cart_box__message--{{ loop.index }}" class="message">
                            <p class="errormsg bg-danger">
                                <svg class="cb cb-warning"><use xlink:href="#cb-warning" /></svg>{{ error|trans|nl2br }}
                            </p>
                        </div>
                    {% endfor %}'.$search;
        $source = str_replace($search, $replace, $source);

        $event->setSource($source);
    }