Thanks. I uploaded and installed a fresh macOS TestFlight build of the focused probe project:
https://github.com/wfried/apptransaction-probe
The updated probe explicitly handles StoreKitError.networkError(URLError), but in the TestFlight-installed build the thrown error is not networkError. It is StoreKitError.unknown:
Bundle ID: com.soundcity.AppTransactionProbe
App version: 1.0
Build: 2
deviceVerificationID available: true
deviceVerificationID prefix: CA91ED5D...
AppTransaction.shared threw
error type: StoreKitError
error localizedDescription: Unable to Complete Request
error StoreKitError: unknown
error StoreKitError case: unknown
error NSError domain: StoreKit.StoreKitError
error NSError code: 2
So there does not appear to be an underlying URLError available from the public StoreKitError value.
Can you clarify what setup is required for AppTransaction.shared to return a verified AppTransaction in a macOS TestFlight build? The App Store Connect app exists, the build was installed through TestFlight, and AppStore.deviceVerificationID is available in the same process.