ios – Why is that this inflicting an unrecognized selector error?

    import UIKit
import Toolbar

class ViewController: UIViewController {
  
  lazy var toolbar: Toolbar = {
    let toolbar: Toolbar = Toolbar([
      Toolbar.Item(title: "BUTTON", target: nil, action: #selector(test(_:))),
      Toolbar.Item(title: "BUTTON", target: nil, action: nil),
      Toolbar.Item(title: "BUTTON", target: nil, action: nil)
    ])
    return toolbar
  }()
  
  
  override func viewDidLoad() {
    tremendous.viewDidLoad()
    self.view.backgroundColor = .systemBackground
    self.view.addSubview(self.toolbar)
  }
  
  @objc func check(_ sender: Any) {
    print("hi there")
  }
}

After I press the primary toolbar button the app crashes with:

*** Terminating app as a result of uncaught exception 'NSInvalidArgumentException', motive: '-[NSNull test:]: unrecognized selector despatched to occasion 0x1de715eb0'
terminating with uncaught exception of sort NSException
CoreSimulator 802.6 - Gadget: iPhone 13 mini (41207433-2958-4380-93E0-D0448B566794) - Runtime: iOS 15.4 (19E240) - DeviceType: iPhone 13 mini
(lldb) 

I am unable to determine how I’m calling the check perform incorrectly?