public void ShouldReturnEmptyListWhenGettingMoreChatMessagesByIdIsNull()
{
_chatMessageRepository = new Mock<IChatMessageRepository>();
_chatMessageRepository.Setup(a => a.GetMoreChatMessages(It.IsAny<int>(), It.IsAny<int>(), It.IsAny<int>(), It.IsAny<int>()))
.Returns(new List<ChatMessage>());
_userRepository = new Mock<IUserRepository>();
_chatMessagesLogic = new ChatMessagesLogic(_chatMessageRepository.Object, _userRepository.Object);
var result = _chatMessagesLogic.GetMoreChatMessagesByUser(1, 2, 15);
Assert.IsNotNull(result);
Assert.IsInstanceOf(typeof(List<Common.Contracts.ChatMessage>), result);
Assert.AreEqual(0, result.Count);
}