public async void PostId_Update_Valid_Reference()
        {
            Mock <IVoteRepository> voteRepository = new Mock <IVoteRepository>();

            voteRepository.Setup(x => x.PostByPostId(It.IsAny <int>())).Returns(Task.FromResult <Post>(new Post()));

            var validator = new ApiVoteServerRequestModelValidator(voteRepository.Object);
            await validator.ValidateUpdateAsync(default(int), new ApiVoteServerRequestModel());

            validator.ShouldNotHaveValidationErrorFor(x => x.PostId, 1);
        }
        public async void UserId_Create_Valid_Reference()
        {
            Mock <IVoteRepository> voteRepository = new Mock <IVoteRepository>();

            voteRepository.Setup(x => x.UserByUserId(It.IsAny <int>())).Returns(Task.FromResult <User>(new User()));

            var validator = new ApiVoteServerRequestModelValidator(voteRepository.Object);
            await validator.ValidateCreateAsync(new ApiVoteServerRequestModel());

            validator.ShouldNotHaveValidationErrorFor(x => x.UserId, 1);
        }
        public async void VoteTypeId_Create_Invalid_Reference()
        {
            Mock <IVoteRepository> voteRepository = new Mock <IVoteRepository>();

            voteRepository.Setup(x => x.VoteTypeByVoteTypeId(It.IsAny <int>())).Returns(Task.FromResult <VoteType>(null));

            var validator = new ApiVoteServerRequestModelValidator(voteRepository.Object);

            await validator.ValidateCreateAsync(new ApiVoteServerRequestModel());

            validator.ShouldHaveValidationErrorFor(x => x.VoteTypeId, 1);
        }