this is some real icky code, not for production use. experiment only.

ContextMenyu.swift

//
//  ContentView.swift
//  ContextMenyu
//
//  Created by Eric Lewis on 9/19/19.
//  Copyright © 2019 Eric Lewis, Inc. All rights reserved.
//

import SwiftUI

struct MenuItem: View {
    typealias Body = Never
    typealias Attributes = UIMenuElement.Attributes
    
    var text: String
    var systemName: String?
    var attributes: Attributes?
    var action: (() -> Void)?
    
    fileprivate var actions: [UIAction]? = nil

    init(_ text: String, systemName: String? = nil, attributes: Attributes? = nil, action: (() -> Void)? = nil) {
        self.text = text
        self.systemName = systemName
        self.attributes = attributes
        self.action = action
    }
    
    init<MenuItems>(_ text: String, systemName: String? = nil, attributes: Attributes? = nil, @ViewBuilder content: () -> MenuItems) where MenuItems: View {
        self.text = text
        self.systemName = systemName
        self.attributes = attributes
        
        let tupleMirror = Mirror(reflecting: content())
        tupleMirror.children.map({ $0.value }).first.map {
            let tupleMirror = Mirror(reflecting: $0)
            let actions: [UIAction] = tupleMirror.children.compactMap({ $0.value as? MenuItem }).map { actionItem in
                guard let attributes = actionItem.attributes else {
                    return UIAction(title: actionItem.text, image: UIImage(systemName: actionItem.systemName ?? "")) { _ in
                        actionItem.action?()
                    }
                }
                                        
                return UIAction(title: actionItem.text, image: UIImage(systemName: actionItem.systemName ?? ""), attributes: attributes) { _ in
                    actionItem.action?()
                }
            }
            
            self.actions = actions
        }
        
    }
    
    var body: Never {
        fatalError("Something very, very bad happened")
    }
}

struct ContextMenyu<Content, MenuItems>: UIViewRepresentable where Content: View, MenuItems: View {
    var content: Content
    var title: String? = nil
    var menuItems: () -> MenuItems

    func makeCoordinator() -> Coordinator {
        Coordinator(self)
    }
    
    func makeUIView(context: Context) -> UIView {
        UIHostingController<Content>(rootView: content).view
    }
    
    func updateUIView(_ uiView: UIView, context: Context) {
        uiView.backgroundColor = .clear
        uiView.addInteraction(UIContextMenuInteraction(delegate: context.coordinator))
    }
    
    class Coordinator: NSObject, UIContextMenuInteractionDelegate {
        var parent: ContextMenyu<Content, MenuItems>

        init(_ parent: ContextMenyu<Content, MenuItems>) {
            self.parent = parent
        }

        func contextMenuInteraction(_ interaction: UIContextMenuInteraction, configurationForMenuAtLocation location: CGPoint) -> UIContextMenuConfiguration? {
            UIContextMenuConfiguration(identifier: nil, previewProvider: nil) { suggestedActions in
                var menuHolder: UIMenu? = nil
                let tupleMirror = Mirror(reflecting: self.parent.menuItems())
                tupleMirror.children.map({ $0.value }).first.map {
                    let tupleMirror = Mirror(reflecting: $0)
                    let actions: [UIMenuElement] = tupleMirror.children.compactMap({ $0.value as? MenuItem }).map { actionItem in
                        if (actionItem.actions?.count ?? 0) > 0 {
                            return UIMenu(title: actionItem.text, image: UIImage(systemName: actionItem.systemName ?? ""), children: actionItem.actions ?? [])
                        } else {
                            guard let attributes = actionItem.attributes else {
                                return UIAction(title: actionItem.text, image: UIImage(systemName: actionItem.systemName ?? "")) { _ in
                                    actionItem.action?()
                                }
                            }
                                                    
                            return UIAction(title: actionItem.text, image: UIImage(systemName: actionItem.systemName ?? ""), attributes: attributes) { _ in
                                actionItem.action?()
                            }
                        }
                    }
                    
                    menuHolder = UIMenu(title: self.parent.title ?? "", children: actions)
                }
                
                guard let menu = menuHolder else {
                    return nil
                }
                
                return menu
            }
        }
    }
}

extension View {
    func contextMenyu<MenuItems>(_ title: String? = nil, @ViewBuilder menuItems: @escaping () -> MenuItems) -> some View where MenuItems: View {
        self.opacity(0)
            .overlay(ContextMenyu(content: self, title: title, menuItems: menuItems))
    }
}

struct ContentView: View {
    var body: some View {
        VStack {
            Text("Menu")
                .contextMenu {
                    Text("test")
                    Text("test")
                    Text("Testing")
            }
            Text("")
            Text("Menyu")
                .contextMenyu {
                    MenuItem("test") {
                        MenuItem("test")
                        MenuItem("test")
                    }
                    MenuItem("test")
                    MenuItem("Testing", systemName: "gear", attributes: .destructive)
            }
        }
        
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}