DIP_6_NotificationService_sendNotificationForUser.cs

[TestMethod]
public void isNonPremiumUserMailSentAndValid()
{
  var user            = new User("A", "A@B.com", false);
  var expectedSubject = "Notification";
  var expectedMessage = "Dear A this is a Notification!";

  var sendMail = Mock.Create<SendMail>();

  new NotificationService(sendMail).sendNotificationForUser(user);

  Mock.Assert(
        () => sendMail.sendMail(user.EMailAddress, expectedSubject, expectedMessage),
        Occurs.Once(),
      "sendMail() wasn't called as expected!"
    );
 }

[TestMethod]
public void isPremiumUserMailSendAndValid()
{
 var user = new User("Premium", "Premium@User.com", true);
 var expectedSubject = "Notification";
 var expectedMessage = "Dear Premium this is a Notification! -> Additional Information for Premium Users!";

 var sendMail = Mock.Create<SendMail>();

 new NotificationService(sendMail).sendNotificationForUser(user);

 Mock.Assert(
       () => sendMail.sendMail(user.EMailAddress, expectedSubject, expectedMessage),
       Occurs.Once(),
       "sendMail() wasn't called as expected!"
     );
}