Default implementation of sending notification and adding observer before restructuring to write test cases

UnitTesting.playground

class CurrentLocationProvider {
    static let authChangedNotification = Notification.Name("AuthChanged")
    func notifyAuthChanged() {
        let name = CurrentLocationProvider.authChangedNotification
        NotificationCenter.default.post(name: name, object: self)
    }
}


class PointsOfInterestTableViewController {
    var observer: AnyObject?
    init() {
        let name = CurrentLocationProvider.authChangedNotification
        observer = NotificationCenter.default.addObserver(forName: name, object: nil, queue: .main) { [weak self] _ in
            self?.handleAuthChanged()
        }
    }

    var didHandleNotification = false
    func handleAuthChanged() {
        didHandleNotification = true
    }
}