There is A Square Gift Card listed in the Card-not-present success state values here (specifically card number 7783 3200 0000 0000) but I do not think this card is actually usable for testing Gift Card flows.
When using this card # from the client app, we receive an error: There is no giftcard associated with that nonce. when trying to pass the resulting noce in to the POST /v2/gift-cards/from-nonce endpoint.
Is this expected, or are we doing something wrong when testing our Gift Card flows?
This is expected at this time. The sandbox test value doesn’t currently support RetrieveGiftCardFromNonce. We’re constantly working to improve our features based on feedback like this, so I’ll be sure to share your request to the API product team. 
1 Like
thanks for your response Brian!
Does the sandbox support RetrieveGiftCardFromGAN?
Can you clarify the limitations of the square sandbox vis a vis Gift Card management and using them to pay for orders?
Yes, it works with gift cards created in sandbox. Just not with the test value.