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

                client.Get(1, "reference");

                gitHubClient.Received().Repository.Commit.Get(1, "reference");
            }
            public void EnsuresNonNullArguments()
            {
                var gitHubClient = Substitute.For<IGitHubClient>();
                var client = new ObservableRepositoryCommitsClient(gitHubClient);

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

                Assert.Throws<ArgumentNullException>(() => client.Get(1, null));

                Assert.Throws<ArgumentException>(() => client.Get("", "name", "reference"));
                Assert.Throws<ArgumentException>(() => client.Get("owner", "", "reference"));
                Assert.Throws<ArgumentException>(() => client.Get("owner", "name", ""));

                Assert.Throws<ArgumentException>(() => client.Get(1, ""));
            }