supersonicbyte

SKTestSession testing failures

With iOS 17, Apple shipped a new API allows us to simulate errors when unit testing StoreKit. The API exposes a method called setSimulatedError(_ error: API.Failure?, forAPI api: API) which is intended to be used on a instance of a SKTestSession.

For example, we would use the API to simulate a NetworkError for the purchase API.

try await session.setSimulatedError(.generic(.networkError(URLError(.badURL, userInfo: [:]))), forAPI: .purchase)

This is a great addition and it allows us to test possible error handling flows we have in our code. One thing I encountered when working with this API is that the simulated errors would persist even if I called

 try await session.setSimulatedError(nil, forAPI: .purchase)

as outlined in the WWDC session.

The current workaround for this is to call the resetToDefaultState method on the session before each test executes.

session.resetToDefaultState()

Until next time, M.