Make sheet the exact size of the content inside

Let's say I have a custom view inside of a sheet, something like this

VStack {
   Text("Title")
   Text("Some very long text ...")
}
.padding()
.presentationDetents([.height(250)])

How can I get the exact height of the VStack and pass it to the presentationDetents modifier so that the height of the sheet is exactly the height of the content inside?

Using the general idea made by @jnpdx including some updates such as reading the size of the overlay instead of the background, here is what works for me:

struct ContentView: View {
    @State private var showSheet = false
    @State private var sheetHeight: CGFloat = .zero

    var body: some View {
        Button("Open sheet") {
            showSheet = true
        }
        .sheet(isPresented: $showSheet) {
            VStack {
                Text("Title")
                Text("Some very long text ...")
            }
            .padding()
            .overlay {
                GeometryReader { geometry in
                    Color.clear.preference(key: InnerHeightPreferenceKey.self, value: geometry.size.height)
                }
            }
            .onPreferenceChange(InnerHeightPreferenceKey.self) { newHeight in
                sheetHeight = newHeight
            }
            .presentationDetents([.height(sheetHeight)])
        }
    }
}

struct InnerHeightPreferenceKey: PreferenceKey {
    static let defaultValue: CGFloat = .zero
    static func reduce(value: inout CGFloat, nextValue: () -> CGFloat) {
        value = nextValue()
    }
}