public void ShouldThrowExceptionWhenGettingToUserIsNullOnChatMessagesByName()
{
_chatMessageRepository = new Mock<IChatMessageRepository>();
_chatMessageRepository.Setup(a => a.GetChatMessages(It.IsAny<int>(), It.IsAny<int>(), It.IsAny<int>()))
.Returns(new List<ChatMessage>());
_userRepository = new Mock<IUserRepository>();
_userRepository.SetupSequence(a => a.Find(It.IsAny<Expression<Func<User, bool>>>(), false))
.Returns(_user)
.Returns(new List<User>());
_chatMessagesLogic = new ChatMessagesLogic(_chatMessageRepository.Object, _userRepository.Object);
var result = Assert.Throws<BlogException>(() => _chatMessagesLogic.GetChatMessagesByUser("FooBar", "Drums"));
Assert.AreEqual("No user found with username Drums", result.Message);
}