public async Task EnsuresNonNullArguments()
            {
                var client = new ObservableRepositoryBranchesClient(Substitute.For<IGitHubClient>());
                var update = new List<string>() { "test" };

                Assert.Throws<ArgumentNullException>(() => client.UpdateRequiredStatusChecksContexts(null, "repo", "branch", update));
                Assert.Throws<ArgumentNullException>(() => client.UpdateRequiredStatusChecksContexts("owner", null, "branch", update));
                Assert.Throws<ArgumentNullException>(() => client.UpdateRequiredStatusChecksContexts("owner", "repo", null, update));
                Assert.Throws<ArgumentNullException>(() => client.UpdateRequiredStatusChecksContexts("owner", "repo", "branch", null));

                Assert.Throws<ArgumentNullException>(() => client.UpdateRequiredStatusChecksContexts(1, null, update));
                Assert.Throws<ArgumentNullException>(() => client.UpdateRequiredStatusChecksContexts(1, "branch", null));

                Assert.Throws<ArgumentException>(() => client.UpdateRequiredStatusChecksContexts("", "repo", "branch", update));
                Assert.Throws<ArgumentException>(() => client.UpdateRequiredStatusChecksContexts("owner", "", "branch", update));
                Assert.Throws<ArgumentException>(() => client.UpdateRequiredStatusChecksContexts("owner", "repo", "", update));

                Assert.Throws<ArgumentException>(() => client.UpdateRequiredStatusChecksContexts(1, "", update));
            }
            public void RequestsTheCorrectUrlWithRepositoryId()
            {
                var gitHubClient = Substitute.For<IGitHubClient>();
                var client = new ObservableRepositoryBranchesClient(gitHubClient);
                var update = new List<string>() { "test" };

                client.UpdateRequiredStatusChecksContexts(1, "branch", update);

                gitHubClient.Repository.Branch.Received()
                    .UpdateRequiredStatusChecksContexts(1, "branch", update);
            }