Check if subclass overrides a method

Question

Is it possible to check whether a subclass implements a method that exists either in its immediate superclass or in some superclass of its superclass, etc?

E.g. I subcla

Answer 1

Adapted for Swift 4.0 (and added an optional baseClass BELOW which the algorithm looks for overrides):

extension NSObject {

    func checkIf(overrides selector: Selector, baseClass: AnyClass? = nil) -> Bool {
        guard var objSuperClass = self.superclass else { return false }

        var isOverridden = false

        while objSuperClass != nil {
            isOverridden = object.method(for: selector) != objSuperClass?.instanceMethod(for: selector)
            if isOverridden {
                break
            }
            objSuperClass = objSuperClass?.superclass()
            if objSuperClass == baseClass {
                break
            }
        }

        return isOverridden
    }
}