title: Xcode unit test warning when declare variable
body: <p>Can anyone explain me why when i declare variable like this:</p>
  <pre class="lang-swift prettyprint-override"><code>private let viewModel = TermsAndConditionViewModel()
      
  // TermsAndConditionViewModel
  
  class TermsAndConditionViewModel {
  
      private let permissionsModel: PermissionsModel
      private let userSession: UserSessionManager
     
      init(
          permissionsModel: PermissionsModel = PermissionsModelImpl(),
          userSession: UserSessionManager = UserSessionManager.shared
      ) {
          self.permissionsModel = permissionsModel
          self.userSession = userSession
      }
  }
  </code></pre>
  <p>and run test in Xcode I got warning like <a href="https://i.stack.imgur.com/qEL2z.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qEL2z.png" alt="enter image description here" /></a></p>
  <p>update: there is no message about warning.
  and this is when I check in Xcode/Coverage</p>
  <p><a href="https://i.stack.imgur.com/38pMx.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/38pMx.png" alt="enter image description here" /></a></p>
  <p>Thank for your help.</p>