Crash on account creation, error and button code included

Question

I am getting the following error around 20% of the time I try to create an account: Can someone please help me in diagnosing the issue please

Crashed: com.apple.main-thread EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0000000000000010

    Crashed: com.apple.main-thread
0  libobjc.A.dylib                0x2820 objc_msgSend + 32
1  UIKitCore                      0x2004a4 -[UIViewController dealloc] + 772
2  UIKitCore                      0x1fe0cc -[UINavigationController dealloc] + 308
3  UIKitCore                      0x486bbc -[_UISplitViewControllerColumnContents .cxx_destruct] + 44
4  libobjc.A.dylib                0x20a4 object_cxxDestructFromClass(objc_object*, objc_class*) + 116
5  libobjc.A.dylib                0x6e00 objc_destructInstance + 80
6  libobjc.A.dylib                0x104fc _objc_rootDealloc + 80
7  CoreFoundation                 0x2a26c cow_cleanup + 168
8  CoreFoundation                 0x62538 -[__NSDictionaryM dealloc] + 148
9  libobjc.A.dylib                0x20a4 object_cxxDestructFromClass(objc_object*, objc_class*) + 116
10 libobjc.A.dylib                0x6e00 objc_destructInstance + 80
11 libobjc.A.dylib                0x104fc _objc_rootDealloc + 80
12 libobjc.A.dylib                0x20a4 object_cxxDestructFromClass(objc_object*, objc_class*) + 116
13 libobjc.A.dylib                0x6e00 objc_destructInstance + 80
14 libobjc.A.dylib                0x104fc _objc_rootDealloc + 80
15 UIKitCore                      0x2008d8 -[UIResponder dealloc] + 124
16 UIKitCore                      0x2005dc -[UIViewController dealloc] + 1084
17 libobjc.A.dylib                0x21d4 AutoreleasePoolPage::releaseUntil(objc_object**) + 196
18 libobjc.A.dylib                0x5bdc objc_autoreleasePoolPop + 256
19 UIKitCore                      0x1a0444 -[_UIAfterCACommitBlock run] + 92
20 UIKitCore                      0x1a0364 -[_UIAfterCACommitQueue flush] + 168
21 UIKitCore                      0x1a0278 _runAfterCACommitDeferredBlocks + 496
22 UIKitCore                      0x3eee4 _cleanUpAfterCAFlushAndRunDeferredBlocks + 108
23 UIKitCore                      0x4fd608 _UIApplicationFlushCATransaction + 72
24 UIKitCore                      0x64de00 _UIUpdateSequenceRun + 84
25 UIKitCore                      0xcb1944 schedulerStepScheduledMainSection + 144
26 UIKitCore                      0xcb0ea0 runloopSourceCallback + 92
27 CoreFoundation                 0xd3208 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 28
28 CoreFoundation                 0xdf864 __CFRunLoopDoSource0 + 176
29 CoreFoundation                 0x646c8 __CFRunLoopDoSources0 + 244
30 CoreFoundation                 0x7a1c4 __CFRunLoopRun + 828
31 CoreFoundation                 0x7f4dc CFRunLoopRunSpecific + 612
32 GraphicsServices               0x135c GSEventRunModal + 164
33 UIKitCore                      0x39d37c -[UIApplication _run] + 888
34 UIKitCore                      0x39cfe0 UIApplicationMain + 340
35 SwiftUI                        0x1bc3d8 OUTLINED_FUNCTION_895 + 2472
36 SwiftUI                        0x1229b0 block_copy_helper.1 + 496
37 SwiftUI                        0x10ca54 OUTLINED_FUNCTION_901 + 2752
38 AppName                   0x7844 main + 23 (AppName.swift:23)
39 ???                            0x1ab1b0dec (Missing)

I don't get this crash when I am running in the simulator only when I run trough Firestore App distribution.

Code of the button causing crash and the viewModels:

@StateObject var viewModel: AuthViewModel.CreateAccountViewModel
...
Button("Create Account", action: viewModel.submit)

AuthViewModel:

func makeCreateAccountViewModel() -> CreateAccountViewModel {
        return CreateAccountViewModel(action: authService.createAccount(name:email:password:))
    }

class CreateAccountViewModel: FormViewModel<(name: String, email: String, password: String)> {
        convenience init(action: @escaping Action) {
            self.init(initialValue: (name: "", email: "", password: ""), action: action)
        }
    }

FormViewModel:

@MainActor
@dynamicMemberLookup
class FormViewModel<Value>: ObservableObject {
    typealias Action = (Value) async throws -> Void
    
    @Published var value: Value
    @Published var error: Error?
    @Published var isWorking = false
    
    subscript<T>(dynamicMember keyPath: WritableKeyPath<Value, T>) -> T {
        get { value[keyPath: keyPath] }
        set { value[keyPath: keyPath] = newValue }
    }
    
    private let action: Action
    
    init(initialValue: Value, action: @escaping Action) {
        self.value = initialValue
        self.action = action
    }
    
    nonisolated func submit() {
        Task {
            await handleSubmit()
        }
    }
    
    private func handleSubmit() async {
        isWorking = true
        do {
            try await action(value)
        } catch {
            print("[FormViewModel] Cannot submit: \(error)")
            self.error = error
        }
        isWorking = false
    }
}

AuthService:

private let auth = Auth.auth()

func createAccount(email: String, password: String) async throws {
        let result = try await auth.createUser(withEmail: email, password: password)
        try await result.user.updateProfile(\.displayName, to: email)
    }

private extension FirebaseAuth.User {
    func updateProfile<T>(_ keyPath: WritableKeyPath<UserProfileChangeRequest, T>, to newValue: T) async throws {
        var profileChangeRequest = createProfileChangeRequest()
        profileChangeRequest[keyPath: keyPath] = newValue
        try await profileChangeRequest.commitChanges()
    }
}

Please ask any questions and if there is anything that needs to be added to make it clearer.

Thanks

Further edits: After completing the suggestion from lorem ipsum I turned on "strict/complete concurrency" This gives me the following "error" on this code:

func createAccount(email: String, password: String) async throws {
        let result = try await auth.createUser(withEmail: email, password: password)
        try await result.user.updateProfile(\.displayName, to: email)
    }

let result part: Non-sendable type 'AuthDataResult' returned by call from main actor-isolated context to non-isolated instance method 'createUser(withEmail:password:)' cannot cross actor boundary try await part: Non-sendable type 'WritableKeyPath<UserProfileChangeRequest, String?>' exiting main actor-isolated context in call to non-isolated instance method 'updateProfile(_:to:)' cannot cross actor boundary

Does anyone have advice on fixing this?

Thanks

Answer 1

The purpose of the MainActor wrapper is to keep UI updates on the main actor. You remove the safety by nonisolating and “leaking” the Task.

Try something like

@State private var isProcessing: Bool = false

And

            Button {
                //This can start/stop a task
                isProcessing.toggle()
            } label: {
                Text("Create Account")
                    .task(id: isProcessing) {
                        guard isProcessing else {
                            return
                        }
                        await viewModel.handleSubmit()
                        isProcessing = false
                    }

            }

This will allow you to "hold on" to the task in the spirit of concurrency.

I would also suggest turning on "strict/complete concurrency" or at the very least "targeted".

Why does `Task<C, Error>` work even though `C` is a class which is not `Sendable`, or is it?

And add

-Xfrontend -warn-concurrency 
-Xfrontend -enable-actor-data-race-checks

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