[SOLVED] Xcode Cloud can't build SwiftUI archive that builds locally

Xcode Cloud can't build SwiftUI archive that builds locally

I'm having problems with Xcode Cloud building my SwiftUI app since I added dummy data for SwiftData for previews (in the "Preview Content" folder) with the error "Cannot find 'SampleData' in scope":

Error log

The dummy data is used in the view's previews like the following for views that use queries themselves

#Preview {
    RecentListView()
        .modelContainer(SampleData.shared.modelContainer)
}

and like this for others that get passed individual elements

#Preview(traits: .modifier(SampleDataPreview())) {
    @Previewable @Query var workdays: [WorkDay]
    NavigationStack {
        SummaryView(filteredWorkdays: workdays)
    }
}

Locally all previews work as expected and I can build the whole project with Xcode just fine.

I added the SampleData.swift file to the

Development assets (in the General tab of the target)
Copy bundle resources (in the Build phases tab of the target)

hoping this would fix the Xcode cloud build process but so far this hasn't helped and I don't really know what else to try anymore.

Solution

Wrapping all #Previews with #if DEBUG makes the project build again for AppStore Connect. Seems to be an issue with the sample data in the Preview Content folder, also see: https://stackoverflow.com/a/77646138/28960225

Thanks @Joakim!