Deinit method is not called in Xcode 10 Beta 6 playground

Question

I was exploring memory management concept and found deinit method is not calling in Xcode 10 beta 6 playground. Initially I thought may be some pro

Answer 1

This issue seems to still be present in Xcode 10.0 (10A255). I have playground with the following code:

class Person {
    var name: String

    func buy(car: Car) {
        car.owner = self
    }

    init(name: String) {
        self.name = name
        print("Person \(name) is initalized")
    }

    deinit {
        print("Person \(name) is being deinitialized")
    }
}


class Car {
    let model: String
    weak var owner: Person?

    init(model: String) {
        self.model = model
        print("Car \(model) is initialized")
    }

    deinit {
        print("Car \(model) is being deinitialized")
    }
}

print("===== before do =====")
do {
    print("    ---- do begin -----")
    let johnny = Person(name: "John")
    let porsche = Car(model: "Carrera4")
    johnny.buy(car: porsche)
    print("    ---- do end -----")
}
print("===== after do =====")

In Xcode 9.4.1 both Car's and Person's deinit are executed, but in Xcode 10.0 (10A255) the Person's deinit method is not executed.

The same code inside a test macOS project works as expected (both deinit executed) in Xcode 9.4.1 as well as Xcode 10.0 (10A255)