public async Task IfLinksInCache_ReturnsMatchingLink()
            {
                _mockRepo.Setup(x => x.GetShortLinks())
                .Returns(Task.FromResult(new List <ShortLinkItem>
                {
                    new ShortLinkItem("abc", "blahblahabc"),
                    new ShortLinkItem("def", "blahblah")
                }));

                var result = await _sut.GetByShortCode("abc");

                result.URL.Should().Be("blahblahabc");
            }
            public void IfLinksInCache_ReturnsMatchingLink()
            {
                _mockRepo.Setup(x => x.GetShortLinks())
                .Returns(new List <ShortLinkItem>
                {
                    new ShortLinkItem("abc", "blahblahabc"),
                    new ShortLinkItem("def", "blahblah")
                });

                var result = _sut.GetByShortCode("abc");

                result.URL.Should().Be("blahblahabc");
            }