public async Task GetAllMessagesShouldReturnAllMessages()
{
await this.PopulateMessages();
var service = new MessengerService(this.conversationRepository, this.messageRepository);
List <TestMessageViewModel> messages = service
.GetAllMessages <TestMessageViewModel>()
.ToList();
Assert.Equal(2, messages.Count);
Assert.Equal("bbbb", messages[1].Text);
Assert.Equal("cccc", messages[0].UserId);
}