public async Task EnsuresNonNullArguments()
        {
            var client = new ObservableIssuesClient(Substitute.For<IGitHubClient>());

            await Assert.ThrowsAsync<ArgumentNullException>(() => client.Get(null, "name", 1).ToTask());
            await Assert.ThrowsAsync<ArgumentNullException>(() => client.Get("owner", null, 1).ToTask());
            await Assert.ThrowsAsync<ArgumentNullException>(() => client.Get(null, "", 1).ToTask());
            await Assert.ThrowsAsync<ArgumentException>(() => client.Get("", null, 1).ToTask());
        }
        public void EnsuresNonNullArguments()
        {
            var client = new ObservableIssuesClient(Substitute.For<IGitHubClient>());

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

            Assert.Throws<ArgumentException>(() => client.Get("owner", "", 1));
            Assert.Throws<ArgumentException>(() => client.Get("", "name", 1));
        }
        public void GetsFromClientIssueIssueWithRepositoryId()
        {
            var gitHubClient = Substitute.For<IGitHubClient>();
            var client = new ObservableIssuesClient(gitHubClient);

            client.Get(1, 42);

            gitHubClient.Issue.Received().Get(1, 42);
        }
        public void GetsFromClientIssueIssue()
        {
            var gitHubClient = Substitute.For<IGitHubClient>();
            var client = new ObservableIssuesClient(gitHubClient);

            client.Get("fake", "repo", 42);

            gitHubClient.Issue.Received().Get("fake", "repo", 42);
        }