Tutorial won't compile: Meet The Composable Architecture - Improve domain modeling has a compile error

[arusu0629]

Description

I've finished Multiple presentation destinations Section 2 Improve domain modeling
But, I encountered a compile error in switch statement

//  ContactsFeature.swift
//  TCA-Tutorials

import Foundation
import ComposableArchitecture
import SwiftUI

struct Contact: Equatable, Identifiable {
    let id: UUID
    var name: String
}

struct ContactsFeature: ReducerProtocol {
    struct State: Equatable {
        var contacts: IdentifiedArrayOf<Contact> = []
        @PresentationState var destination: Destination.State?
    }
    enum Action: Equatable {
        case addButtonTapped
        case deleteButtonTapped(id: Contact.ID)
        case destination(PresentationAction<Destination.Action>)
        enum Alert: Equatable {
            case confirmDeletion(id: Contact.ID)
        }
    }
    var body: some ReducerProtocolOf<Self> {
        Reduce { state, action in
            switch action { // Switch must be exhaustive. Do you want to add missing cases?
            case .addButtonTapped:
                state.destination = .addContact(
                    AddContactFeature.State(
                        contact: Contact(id: 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 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: /Action.destination) {
            Destination()
        }
    }
}

extension ContactsFeature {
    struct Destination: ReducerProtocol {
        enum State: Equatable {
            case addContact(AddContactFeature.State)
            case alert(AlertState<ContactsFeature.Action.Alert>)
        }
        enum Action: Equatable {
            case addContact(AddContactFeature.Action)
            case alert(ContactsFeature.Action.Alert)
        }
        var body: some ReducerProtocolOf<Self> {
            Scope(state: /State.addContact, action: /Action.addContact) {
                AddContactFeature()
            }
        }
    }
}

struct ContentView: View {
    let store: StoreOf<ContactsFeature>

    var body: some View {
        NavigationStack {
            WithViewStore(self.store, observe: \.contacts) { viewStore in
                List {
                    ForEach(viewStore.state) { contact in
                        HStack {
                            Text(contact.name)
                            Spacer()
                            Button {
                                viewStore.send(.deleteButtonTapped(id: contact.id))
                            } label: {
                                Image(systemName: "trash")
                                    .foregroundColor(.red)
                            }
                        }
                    }
                }
                .navigationTitle("Contacts")
                .toolbar {
                    ToolbarItem {
                        Button {
                            viewStore.send(.addButtonTapped)
                        } label: {
                            Image(systemName: "plus")
                        }
                    }
                }
            }
        }
        .sheet(
            store: self.store.scope(state: \.$destination, action: { .destination($0) }),
            state: /ContactsFeature.Destination.State.addContact,
            action: ContactsFeature.Destination.Action.addContact
        ) { addContactStore in
            NavigationStack {
                AddContactView(store: addContactStore)
            }
        }
        .alert(
            store: self.store.scope(state: \.$destination, action: { .destination($0) }),
            state: /ContactsFeature.Destination.State.alert,
            action: ContactsFeature.Destination.Action.alert
        )
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView(
            store: Store(
                initialState: ContactsFeature.State(
                    contacts: [
                        Contact(id: UUID(), name: "Blob"),
                        Contact(id: UUID(), name: "Blob Jr"),
                        Contact(id: UUID(), name: "Blob Sr"),
                    ]
                ),
                reducer: ContactsFeature()
            )
        )
    }
}

The below code was added when I had selected a fix button in compiler messages

            ...
            case .destination(.dismiss):
                <#code#>
            case .destination(.presented(.addContact(.cancelButtonTapped))):
                <#code#>
            case .destination(.presented(.addContact(.saveButtonTapped))):
                <#code#>
            case .destination(.presented(.addContact(.setName(_)))):
                <#code#>
            }
        }
        .ifLet(\.$destination, action: /Action.destination) {
            Destination()
        }

Thank you for your help 🙏🙏🙏

[mbrandonw]

Which section # and step # exactly did you get a compiler error?

[arusu0629]

@mbrandonw
Thank you for replying message!

Section

Section 2 Improve domain modeling

Step

Step14

Replace the two ifLets that were used at the bottom of the reducer with a single one that runs the Destination reducer whenever the destination state is non-nil.

Error message

Switch must be exhustive
Do you wantto add missing cases?

I've done temporary below code so that I can go to next section

            ...
            // TODO: Need to confirm whether this is really good
            default:
                return .none
            }

[mbrandonw]

Hi @arusu0629, thanks for the report. This #2331 should fix it.