// カートへ追加
        $this->cartService->addProduct($addCartData['product_class_id'], $addCartData['quantity']);

        // 明細の正規化
        $Carts = $this->cartService->getCarts();
        foreach ($Carts as $Cart) {
            $result = $this->purchaseFlow->validate($Cart, new PurchaseContext($Cart, $this->getUser()));    // ★ここでfalse
            // 復旧不可のエラーが発生した場合は追加した明細を削除.
            if ($result->hasError()) {
                $this->cartService->removeProduct($addCartData['product_class_id']);    // ★ここでエラー
                foreach ($result->getErrors() as $error) {
                    $errorMessages[] = $error->getMessage();
                }
            }
            foreach ($result->getWarning() as $warning) {
                $errorMessages[] = $warning->getMessage();
            }
        }