/**
  * Determine if the given user is subscribed to the given plan.
  *
  * @param  \Illuminate\Contracts\Auth\Authenticatable  $user
  * @param  string  $subscription
  * @param  string  $plan
  * @param  bool  $defaultSubscription
  * @return bool
  */
 protected function subscribed($user, $subscription, $plan, $defaultSubscription)
 {
     if (!$user) {
         return false;
     }
     return $defaultSubscription && $user->onGenericTrial() || $user->subscribed($subscription, $plan);
 }