/**
  * Check if this coupon is already applied to the cart.
  *
  * @param CartInterface   $cart   Cart
  * @param CouponInterface $coupon Coupon
  *
  * @throws CouponAlreadyAppliedException Coupon already applied
  */
 public function validateDuplicatedCoupon(CartInterface $cart, CouponInterface $coupon)
 {
     $cartCoupon = $this->cartCouponRepository->findOneBy(['cart' => $cart, 'coupon' => $coupon]);
     if (null !== $cartCoupon) {
         throw new CouponAlreadyAppliedException();
     }
 }
 /**
  * Check if this coupon is already applied to the cart
  *
  * @param CartCouponOnApplyEvent $event Event
  *
  * @throws CouponAlreadyAppliedException
  */
 public function checkDuplicates(CartCouponOnApplyEvent $event)
 {
     $cartCoupon = $this->cartCouponRepository->findOneBy(['cart' => $event->getCart(), 'coupon' => $event->getCoupon()]);
     if (null !== $cartCoupon) {
         throw new CouponAlreadyAppliedException();
     }
 }