public async void Text_Update_length()
        {
            Mock <ICommentRepository> commentRepository = new Mock <ICommentRepository>();

            commentRepository.Setup(x => x.Get(It.IsAny <int>())).Returns(Task.FromResult(new Comment()));

            var validator = new ApiCommentRequestModelValidator(commentRepository.Object);
            await validator.ValidateUpdateAsync(default(int), new ApiCommentRequestModel());

            validator.ShouldHaveValidationErrorFor(x => x.Text, new string('A', 701));
        }
        public async void Text_Create_null()
        {
            Mock <ICommentRepository> commentRepository = new Mock <ICommentRepository>();

            commentRepository.Setup(x => x.Get(It.IsAny <int>())).Returns(Task.FromResult(new Comment()));

            var validator = new ApiCommentRequestModelValidator(commentRepository.Object);
            await validator.ValidateCreateAsync(new ApiCommentRequestModel());

            validator.ShouldHaveValidationErrorFor(x => x.Text, null as string);
        }