Unit test for Binding Reducer

[CharanPera]

Hi, How can i write Unit test for the below reducer

case binding(BindingAction<State>)

case .binding(\.pickerSelection):
  return .run { [value = state.pickerSelection] send in
        await send(.pickerChanged(value))
   }

[mbrandonw]

Hi @CharanPera, before telling you how to write a test for that I would want to recommend that perhaps you do not need the pickerChanged action. You are sending an action to tell the reducer that something changed, but the .binding(\.pickerSelection) action is exactly that already. Whatever logic you want to do in .pickerChanged can just be done in .binding(\.pickerSelection).

However, having said that, you would test this code like so:

// Assuming a 'store = TestStore(…)' has been set up

await store.send(.binding(\.pickerSelection, 1)) {
  // Assert on anything that changed
}
await store.receive(\.pickerChanged) {
  // Assert on anything that changed
}