LukePOLO\LaraCart\LaraCart::addItem PHP Method

    public function addItem(CartItem $cartItem)
    {
        $itemHash = $cartItem->generateHash();
        if ($this->getItem($itemHash)) {
            $this->getItem($itemHash)->qty += $cartItem->qty;
        } else {
            $this->cart->items[] = $cartItem;
        }
        $this->events->fire('laracart.addItem', $cartItem);
        return $cartItem;
    }