Diffable-Data-Source-Setup.swift

enum Section : CaseIterable {
  case one
  case two
}

class ViewController: UIViewController {

    private let tableView = UITableView(frame: .zero, style: .insetGrouped)
    private let cellReuseIdentifier = "cellId"
    private lazy var dataSource = makeDataSource()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        tableView.register(UITableViewCell.self,forCellReuseIdentifier: cellReuseIdentifier)
        view.addSubview(tableView) //additional autolayout setup in the source code
        
        tableView.dataSource = dataSource
        updateDataSource(animated: true)
    }
     
    func makeDataSource() -> UITableViewDiffableDataSource<Section, Movies> {
            let reuseIdentifier = cellReuseIdentifier

            return UITableViewDiffableDataSource(
                tableView: tableView,
                cellProvider: {  tableView, indexPath, movie in
                    let cell = tableView.dequeueReusableCell(
                        withIdentifier: reuseIdentifier,
                        for: indexPath)

                    cell.textLabel?.text = movie.name
                    
                    return cell
                }
            )
        }   
}