modify addQuantity method

core/lib/Thelia/Model/CartItem.php

@@ -7,6 +7,7 @@ use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 use Thelia\Core\Event\CartEvent;
 use Thelia\Core\Event\TheliaEvents;
 use Thelia\Model\Base\CartItem as BaseCartItem;
+use Thelia\Model\ConfigQuery;
 
 class CartItem extends BaseCartItem
 {
@@ -26,9 +27,41 @@ class CartItem extends BaseCartItem
         }
     }
 
+    public function postUpdate(ConnectionInterface $con = null)
+    {
+        if ($this->dispatcher) {
+            $cartEvent = new CartEvent($this->getCart());
+
+            $this->dispatcher->dispatch(TheliaEvents::CART_MODIFYITEM, $cartEvent);
+        }
+    }
+
+
+    /**
+     * @param $value
+     * @return $this
+     */
     public function addQuantity($value)
     {
-        $this->setQuantity($this->getQuantity() + $value);
+        $currentQuantity = $this->getQuantity();
+
+        $newQuantity = $currentQuantity + $value;
+
+        if($newQuantity <= 0)
+        {
+            $newQuantity = $currentQuantity;
+        }
+
+        if(ConfigQuery::read("verifyStock", 1) == 1)
+        {
+            $productSaleElements = $this->getProductSaleElements();
+
+            if($productSaleElements->getQuantity() < $newQuantity) {
+                $newQuantity = $currentQuantity;
+            }
+        }
+
+        $this->setQuantity($currentQuantity);
 
         return $this;
     }