Showcasing the ViewController's dismiss method being broken in packages

BrokenDismiss.swift

import XCTest
import UIKit

@testable import DismissTest

class TopLevelUIUtilities {

    private var rootWindow: UIWindow!

    func setupTopLevelUI(withViewController viewController: UIViewController) {
//        let windowScene = UIApplication.shared.connectedScenes.first as! UIWindowScene
        rootWindow = UIWindow()
        rootWindow.rootViewController = viewController
        rootWindow.makeKeyAndVisible()
        rootWindow.isHidden = false
    }
}

final class DismissTestTests: XCTestCase {

    private var presentingViewController: UIViewController!
    private var topLevelUIUtilities: TopLevelUIUtilities!

    override func setUp() {
        super.setUp()
//        presentingViewController = UIViewController()
        topLevelUIUtilities = TopLevelUIUtilities()
//        topLevelUIUtilities.setupTopLevelUI(withViewController: presentingViewController)
    }

    func testExample() throws {
        let expectation = XCTestExpectation(description: #function)

        let v1 = UIViewController()
        let v2 = UIViewController()
        topLevelUIUtilities.setupTopLevelUI(withViewController: v1)

        v1.present(v2, animated: true)
        // after the above line,
        //
        // 1) if `makeKeyAndVisible` was executed in `setupTopLevelUI`, presentingViewController.presentedViewCOntroller is not nil
        // but the closure in the `dismiss` call later never gets called
        //
        // 2) if `makeKeyAndVisible` is commented out in `setupTopLevelUI`, presentingViewController.presentedViewCOntroller is nil
        // and the following is printed on the console, which makes sense
        // [Presentation] Attempt to present <UnitTests.MyViewController: 0x15d704940> on <UIViewController: 0x15ef0b200> (from <UIViewController: 0x15ef0b200>) whose view is not in the window hierarchy.
        // but in this case the closure in the `dismiss` call later gets called
        //
        // Case 1 is the correct code as we need to setup a window, but cannot understand why dismiss never gets called.
//        DispatchQueue.main.asyncAfter(deadline: .now() + 1) {
        v1.dismiss(animated: false) {
            expectation.fulfill()
        }
//        }

        wait(for: [expectation], timeout: 300)
    }
}

class MyViewController: UIViewController {}