Swift ViewModel Memory Leak?

It’s a true story. It happens by accident.

class VC1 :UIViewController() {
  let viewModel = VC1ViewModel()
  func callVC2(){
     let vc2 = UIViewController()
     vc2.onTap = { (value) in
         self.viewModel.callMom()
  }
  deinit(){
     print("VC1 dead")
  }
}

So, When VC1 dismiss or popup. VC2 and viewModel still in alive.

It prints nothing.

Change callVC2 like this

func callVC2(){
    let vc2 = UIViewController()
    vc2.onTap = { [weak self] (value) in
        self?.viewModel.callMom()
}

When VC1 dismiss or popup, Your memory is free!!!