Cannot compile code example from Testing presentation | Section 1

[qstrnd]

UPD: more details on the environment

• Swift 6.0
• Xcode 16.0.0
• Composable Architecture 1.16.1

I'm following this tutorial, and so far, everything has worked well, except for some fake errors in my tests that disappeared when I ran the compilation.

However, this piece of code does not compile at all:

@MainActor
struct ContactsFeatureTests {
    @Test
    func addFlow() async {
        let store = TestStore(initialState: ContactsFeature.State()) {
            ContactsFeature()

        } withDependencies: {
            $0.uuid = .incrementing
        }

        await store.send(.addButtonTapped) {
            $0.destination = .addContact(
                AddContactFeature.State(
                    contact: Contact(id: UUID(0), name: "")
                )
            )
        }

        await store.send(\.destination.addContact.setName, "Blob Jr.") {
            $0.destination?.addContact?.contact.name = "Blob Jr."
        }

        await store.send(\.destination.addContact.saveButtonTapped)

        await store.receive(
            \.destination.addContact.delegate.saveContact,
            Contact(id: UUID(0), name: "Blob Jr.")
        ) {
            $0.contacts = [
                Contact(id: UUID(0), name: "Blob Jr."),
            ]
        }

        await store.receive(\.destination.dismiss) {
            $0.destination = nil
        }
    }
}

The problem appears when I add this line:

await store.send(\.destination.addContact.setName, "Blob Jr.") {
    $0.destination?.addContact?.contact.name = "Blob Jr."
}

I get the following compiler error message:

Cannot infer key path type from context; consider explicitly specifying a root type

And if I ran the whole code from the example, I get all these error messages:

Am I missing something? I rechecked the code for the ContactsFeature and AddContactFeature and can't see any difference between my code and the one in the tutorial. Here's my ContactsFeature reducer:

@Reducer
struct ContactsFeature {
    @ObservableState
    struct State: Equatable {
        var contacts: IdentifiedArrayOf<Contact> = []
        @Presents var destination: Destination.State?
    }

    enum Action {
        case addButtonTapped
        case deleteButtonTapped(id: Contact.ID)
        case destination(PresentationAction<Destination.Action>)

        enum Alert: Equatable {
            case confirmDeletion(id: Contact.ID)
        }
    }

    @Dependency(\.uuid) var uuid

    var body: some ReducerOf<Self> {
        Reduce { state, action in
            switch action {
            case .addButtonTapped:
                state.destination = .addContact(
                    AddContactFeature.State(
                        contact: Contact(id: self.uuid(), name: "")
                    )
                )
                return .none
            case let .destination(.presented(.addContact(.delegate(.saveContact(contact))))):
                state.contacts.append(contact)
                return .none
            case let .destination(.presented(.alert(.confirmDeletion(id: id)))):
                state.contacts.remove(id: id)
                return .none
            case .destination:
                return .none
            case let .deleteButtonTapped(id: id):
                state.destination = .alert(
                    AlertState {
                        TextState("Are you sure?")

                    } actions: {
                        ButtonState(role: .destructive, action: .confirmDeletion(id: id)) {
                            TextState("Delete")
                        }
                    }
                )
                return .none
            }
        }
        .ifLet(\.$destination, action: \.destination)
    }
}

extension ContactsFeature {
    @Reducer
    enum Destination {
        case addContact(AddContactFeature)
        case alert(AlertState<ContactsFeature.Action.Alert>)
    }
}

extension ContactsFeature.Destination.State: Equatable {}

[shingagyoung]

Don't we need to add Tests to Target Membership for those files that are used inside the test file?

[mbrandonw]

Hi @qstrnd, one of the error messages in your screenshot is simply "Cannot find 'ContactsFeature'", so it would seem that somehow the app code is not being found. Can you please provide the project with the errors so that someone can more easily help?