Bug when adding to cart product after import

Hi,
I’m using the last version of the plugin at the time of writing (2.0.10).

If a user adds to the cart a product (let’s say sku “prod1”) in quantity 1 and shares the cart to another user, the second one can effectively import the cart without any problems.

If then the second user (the one who imported the shared cart) then adds back to the cart the same product again, it looks like there’s a problem in some specific cases:

TALKING ABOUT THE ONLY PRODUCT IN THE CART IN ANY SITUATIONS, SKU “PROD1”

Quantity imported through shared cart: 1
Quantity added from the second user after the import: 1
Final quantity in the cart: 2 -> NO PROBLEMS HERE

Quantity imported through shared cart: 2
Quantity added from the second user after the import: 2
Final quantity in the cart: 4 -> NO PROBLEMS HERE

Quantity imported through shared cart: 1
Quantity added from the second user after the import: 2
Final quantity in the cart: PROBLEM HERE. Looks like if the 2 quantities are different, the quantity is not added to the existing cart item and a new cart item is created instead.

We discovered the problem after a customer was able to finalize an order with multiple “duplicated line items”, having the same sku but different quantities.

I hope it’s clear enough. Any thoughts about it?

Thanks in advance