public void OnlyReturnSessionsForTheSpecifiedSpeaker()
        {
            var sessionRepository = Substitute.For<ISessionRepository>();
            var sessionsLoader = new AllSessionsLoader(sessionRepository);

            sessionsLoader.LoadSessions(new UserProfile {UserName = "******"});

            sessionRepository.Received().GetSessionsSubmittedBy("bob");
        }
 public void ThrowAnException_WhenGivenANullProfile()
 {
     var sessionRepository = Substitute.For<ISessionRepository>();
     var sessionsLoader = new AllSessionsLoader(sessionRepository);
     Assert.Throws<ArgumentNullException>(() => sessionsLoader.LoadSessions(null));
 }