iOS Unit Testing by Example

Extract a Method with Parameters

You may have noticed that ChangePasswordViewController has a lot of repeated code. In the newly extracted validateInputs method, find the first alert code shown here:

Refactoring/Refactoring/ChangePasswordViewController.swift

if newPasswordTextField.text?.isEmpty ?? true {
    let alertController = UIAlertController(
            title: nil,
            message: "Please enter a new password.",
            preferredStyle: .alert)
    let okButton = UIAlertAction(
            title: "OK",
            style: .default) { [weak self] _ in
        self?.newPasswordTextField.becomeFirstResponder()
    }
    alertController.addAction(okButton)
    alertController.preferredAction = okButton
    self.present(alertController, animated: true)
    return ...