public void Given_AnApp_When_SendNotification_Should_Send(string target, string content) { var smsNotificationSender = new NotificationSender(new SmsProviderOne()); try { smsNotificationSender.SendNotification(target, content); } catch (Exception) { //Provider fail switch provider smsNotificationSender.ChangeProvider(new SmsProviderTwo()); } smsNotificationSender.SendNotification(target, content); }