XcodeGen/Tests/Fixtures/TestProject/App_macOS/AppDelegate.swift

import Cocoa

@NSApplicationMain
class AppDelegate: NSObject, NSApplicationDelegate {

    func applicationDidFinishLaunching(_ aNotification: Notification) {
        // Insert code here to initialize your application
    }

    func applicationWillTerminate(_ aNotification: Notification) {
        // Insert code here to tear down your application
    }
}