[BUG] Optimistic payment method deletion in CustomerSheet does not allow for custom removal logic in CustomerAdapter

[kfweber]

Summary

Optimistic payment method deletion in CustomerSheet does not allow for custom removal logic in detachPaymentMethod(paymentMethodId) on CustomerAdapter.

I have a CustomerAdapter implementation with logic in detachPaymentMethod(paymentMethodId) that prevents the removal of payment methods in specific cases. This works in SDK version 24.9.0: A thrown error is displayed in the sheet and the payment method is not removed in the UI.

Starting in version 24.10.0 by commit 8867c51, optimistic removal does not respect a thrown error from detachPaymentMethod(paymentMethodId). The thrown error displays in the sheet, but the payment method is removed from the UI regardless. The payment method is correctly not actually detached in either version; Closing the sheet and re-opening it will fetch and display the payment method again.

The commit states that doing optimistic deletion will lead to a situation where they can still be in the list, which seems to be the exact issue.

To reproduce

Implement a CustomerAdapter where an error is thrown in detachPaymentMethod(paymentMethodId). The payment method will be removed from the UI even though it is not detached on backend.

iOS version

18.4

SDK version

24.10.0

[wooj-stripe]

Hi @kfweber - thanks for writing in, and appreciate your thoughtful description. This change was made to get CustomerSheet in sync with PaymentSheet in order to minimize the time users spend managing their saved payment methods -- specifically we saw users on very bad networks with 10+ payment methods having to wait many seconds just to delete their payment methods. Putting things into perspective, the saved payment method view is technically a best effort view - e.g. if customer adds a new payment method on a different device, the sheet does not automatically refresh. Furthermore, given that an error is being displayed, users do have sense that their payment method wasn't successfully removed, and may require further action to detach the payment method.

I think to remedy this problem we'd need to work on the UX such that a deletion doesn't block a user from returning back to the list of payment methods, and presents a spinner on those payment methods that are 'pending delete'. We'll revisit our roadmap periodically and keep this idea in mind.