reloadData Handler cellForRowAt debug

AVC

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {

        window = UIWindow(frame: UIScreen.main.bounds)
        let aVC = AViewController()
        let nav = UINavigationController(rootViewController: aVC)
        window!.rootViewController = nav
        window!.makeKeyAndVisible()
        return true
    }

BVC

import UIKit

class BViewController: UIViewController {

    @IBOutlet var handlerButton: UIButton! {
        didSet {
            handlerButton.addTarget(self, action: #selector(doHandler), for: .touchUpInside)
        }
    }

    var handler: (() -> Void) = {}

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        print("Disappearing")
    }

    @objc private func doHandler() {
        handler()
    }

}

cellForRowAtDebug

import UIKit

class AViewController: UIViewController {

    @IBOutlet var pushButton: UIButton! {
        didSet {
            pushButton.addTarget(self, action: #selector(pushBVC), for: .touchUpInside)
        }
    }

    @IBOutlet var tableView: UITableView! {
        didSet {
            tableView.dataSource = self
        }
    }

    @objc private func pushBVC() {
        let bVC = BViewController()
        bVC.handler = {
            print("handling")
            self.tableView.reloadData()
        }
        navigationController?.pushViewController(bVC, animated: true)
    }

}

extension AViewController: UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return 20
    }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        print("CellForROwAt")
        return UITableViewCell()
    }
}