[Discussion] NUnit infra in Arcade

[Youssef1313]

The current NUnit infra in Arcade is:

arcade/src/Microsoft.DotNet.Arcade.Sdk/tools/NUnit/NUnit.targets

Lines 4 to 10 in 47888ab

	<ItemGroup>
	<PackageReference Include="Microsoft.TestPlatform" Version="$(MicrosoftTestPlatformVersion)" IsImplicitlyDefined="true" PrivateAssets="all" Publish="true"/>
	<PackageReference Include="NUnit" Version="$(NUnitVersion)" IsImplicitlyDefined="true" PrivateAssets="all" Publish="true"/>
	<PackageReference Include="NUnit3TestAdapter" Version="$(NUnit3TestAdapterVersion)" IsImplicitlyDefined="true" PrivateAssets="all" Publish="true"/>
	</ItemGroup>
	<Import Project="..\VSTest.targets"/>

1. NUnit3TestAdapterVersion is currently an extremely old version (3.15.1) which is from August 2019.
2. Current infra doesn't support MTP currently.
3. NUnit isn't used by many repos/projects.
   • dotnet/runtime uses it in a single project: https://github.com/dotnet/runtime/blob/32fcc41afe5747cf674ca6c62de087ab5fd332eb/src/tools/illink/test/Mono.Linker.Tests/Mono.Linker.Tests.csproj#L6
   • mono/mono.posix uses it in a single project: https://github.com/mono/mono.posix/blob/4cc6078be21184856cdde9878a4e1ed29552934f/tests/Mono.Unix.Tests/Mono.Unix.Tests.csproj#L5
   • I cannot find any other public/internal repos that use NUnit

I think we should either move forward with NUnit (e.g, update deps, support MTP etc), or just remove it completely from Arcade. Given the low usage (only two test projects), I'm leaning towards the latter. A first step would be moving these two projects from NUnit to either xUnit (more consistent with rest of the repo), or MSTest (easier to migrate to). After the migration is done, drop NUnit.targets from Arcade.

[mmitche]

I would go with removing support. How did you do your search for usages?

[Youssef1313]

@mmitche I searched for NUnit</TestRunnerName> on GitHub and DevDiv.

https://devdiv.visualstudio.com/DevDiv/_search?text=%22NUnit%3C/TestRunnerName%3E%22&type=code&lp=dashboard-Project&filters=ProjectFilters%7BDevDiv%7D&pageSize=25

https://github.com/search?q=%22NUnit%3C%2FTestRunnerName%3E%22&type=code

This would definitely exclude any repos I don't have access to though.