public void EnsuresNonEmptyArguments()
            {
                var gitHubClient = Substitute.For <IGitHubClient>();
                var client       = new ObservableGitHubAppsClient(gitHubClient);

                Assert.Throws <ArgumentException>(() => client.GetUserInstallationForCurrent(""));
            }
            public void GetsFromCorrectUrl()
            {
                var gitHubClient = Substitute.For <IGitHubClient>();
                var client       = new ObservableGitHubAppsClient(gitHubClient);

                client.GetUserInstallationForCurrent("ducks");

                gitHubClient.GitHubApps.Received().GetUserInstallationForCurrent("ducks");
            }