Discount BuyXGetY automatically add

[ryanmitchell]

It would be great if there was the option to add Y items automatically to the cart when you have matching X items in your cart. This is really useful for say a free ebook alongside a paperback purchase.

I'd be happy to work on this if it was something you'd consider acceptable?

[glennjacobs]

It's a tricky one as then does the item also get automatically removed when you no longer qualify for the discount?

Happy to consider a PR. But think it would need to go into 0.3 now, as we really need to finish up on 0.2.

[ryanmitchell]

Yeah it would be automatically removed when no longer eligible. And yep it gets complicated :)

I’ll have a go at it over the next couple of weeks - happy for it to wait to 0.3

[glennjacobs]

What if the user already had the item in their cart?

[ryanmitchell]

So I would suggest we use the meta on the cart line to indicate it was 'added_by' another cart line id(s) ... then if that/those cart lines are removed then it would remove the free discount.

The other option would be to flag it as added by a discount, then on cart item add/edit/remove we validate any line items added by discount to ensure they are still valid and if not remove them.

[glennjacobs]

Sounds reasonable.