octokit.net/Octokit.Tests/Reactive/ObservableStatisticsClientTests.cs

using System;
using System.Reactive.Linq;
using System.Threading.Tasks;
using NSubstitute;
using Octokit.Reactive;
using Octokit.Tests.Helpers;
using Xunit;

namespace Octokit.Tests.Reactive
{
    public class ObservableStatisticsClientTests
    {
        public class TheGetMethod
        {
            [Fact]
            public void GetsFromClientIssueMilestone()
            {
                var gitHubClient = Substitute.For<IGitHubClient>();
                var statisticsClient = new ObservableStatisticsClient(gitHubClient);

                statisticsClient.GetContributors("username", "repositoryName");

                gitHubClient.Statistics.Received().GetContributors("username", "repositoryName");
            }

            [Fact]
            public async Task ThrowsIfGivenNullRepositoryName()
            {   
                var statisticsClient = new ObservableStatisticsClient(Substitute.For<IGitHubClient>());
                await AssertEx.Throws<ArgumentNullException>(async () => await statisticsClient.GetContributors("owner", null));
            }

            [Fact]
            public async Task ThrowsIfGivenNullOwnerName()
            {
                var statisticsClient = new ObservableStatisticsClient(Substitute.For<IGitHubClient>());
                await AssertEx.Throws<ArgumentNullException>(async () => await statisticsClient.GetContributors(null, "repositoryName"));
            }
        }
    }
}