public void EnsuresNonNullArguments()
            {
                var client = new ObservableReleasesClient(Substitute.For<IGitHubClient>());

                Assert.Throws<ArgumentNullException>(() => client.GetAssets(null, "name", 1));
                Assert.Throws<ArgumentException>(() => client.GetAssets("", "name", 1));
                Assert.Throws<ArgumentNullException>(() => client.GetAssets("owner", null, 1));
                Assert.Throws<ArgumentException>(() => client.GetAssets("owner", "", 1));
            }
            public void RequestsTheCorrectUrl()
            {
                var gitHubClient = Substitute.For<IGitHubClient>();
                var client = new ObservableReleasesClient(gitHubClient);

                client.GetAssets("fake", "repo", 1);

                gitHubClient.Connection.Received(1).Get<List<ReleaseAsset>>(
                    new Uri("repos/fake/repo/releases/1/assets", UriKind.Relative), null, null);
            }