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

                Assert.Throws<ArgumentNullException>(() => client.GetCommitActivity("owner", null));
                Assert.Throws<ArgumentNullException>(() => client.GetCommitActivity(null, "name"));

                Assert.Throws<ArgumentException>(() => client.GetCommitActivity("", "name"));
                Assert.Throws<ArgumentException>(() => client.GetCommitActivity("owner", ""));
            }
            public void RequestsCorrectUrlWithRepositoryId()
            {
                var gitHubClient = Substitute.For<IGitHubClient>();
                var statisticsClient = new ObservableStatisticsClient(gitHubClient);

                statisticsClient.GetCommitActivity(1);

                gitHubClient.Repository.Statistics.Received().GetCommitActivity(1);
            }