Unity support

[bdovaz]

Unity only supports version 3.8 of Microsoft.CodeAnalysis.CSharp: https://docs.unity3d.com/Manual/roslyn-analyzers.html

Roslynator from what I see is directly using version 4.4.0 right now:

https://github.com/dotnet/roslynator/blob/7bc89125ea3793993a9e47f89872daf212bebe57/src/Directory.Build.props#L16C1-L16C1

This makes it not compatible with Unity:

warning CS8032: An instance of analyzer Roslynator.CSharp.Analysis.AddBracesAnalyzer cannot be created from {UNITY_PROJECT_PATH}\Library\PackageCache\org.nuget.roslynator.analyzers@4.6.0\dotnet\cs\Roslynator.CSharp.Analyzers.dll :
Could not load file or assembly 'Microsoft.CodeAnalysis, Version=4.4.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'. The system cannot find the file specified..

Another very powerful Analyzer is Meziantou, in this case it is compatible with Unity because it offers the analyzers in different versions of Roslyn:

https://github.com/meziantou/Meziantou.Analyzer/blob/cfa7ab74ad7b31a49efcd467a585e39853f2706b/src/Meziantou.Analyzer.pack.csproj#L19

@josefpihrt would it be possible to do the same with Roslynator?

Thank you!

[josefpihrt]

Unfortunately, it's not possible to downgrade Roslynator to Roslyn 3.8 since there is a lot new syntax (e.g. file-scoped namespace) that depends on Roslyn 4.x

To me the question is why Unity references Roslyn 3.8. Roslyn is backward compatible so updating to 4.4 should not be an issue.

@bdovaz Do you know why Unity uses Roslyn 3.8 and not higher version?

Btw. Roslyn 4.4 was released almost year ago (https://www.nuget.org/packages/Microsoft.CodeAnalysis/4.4.0). So I would say Roslynator tries to be compatible by not immediately using newest Roslyn version.

[bdovaz]

I think I can answer you with these links:

https://github.com/Unity-Technologies/mono-unity

https://github.com/Unity-Technologies/roslyn

As you see, Unity has its own forks of mono and roslyn in older versions so they are anchored to that and in Roslyn it is equivalent to 3.8 from what it says in the documentation (link in my first post).

I would love for Unity to use .NET 7, the latest version of Roslyn, etc.... But the reality is not like that...

Meziantou has managed to use the 3.3.x version of the Roslyn packages: https://github.com/meziantou/Meziantou.Analyzer/blob/main/Directory.Build.targets

And those analyzers are very powerful and very similar to Roslynator: https://github.com/meziantou/Meziantou.Analyzer/tree/main/docs

You might be inspired to see how he did it.

I would like to help (I have a good contribution history and I am a mantainer in several repositories) but my experience in Roslyn analyzers is practically null...

[Merichbier]

I'm using VS Code as an external tool for Unity. I've tried to set up Roslynator (VS Code extension) on the project, but nothing is reported. Is it for the same reason mentioned in this report?
Setup:

• VS Code 1.85.1
• C# Dev Kit 1.1.16
• Roslynator 4.8.0

[josefpihrt]

@Merichbier Please see #1338

[Merichbier]

@josefpihrt Thanks for the tips!
I've enabled C# Dev Kit preview 1.2.5, but unfortunately still no report from Roslynator. I've tried on a different (non-Unity) project, a MAUI solution. Same there no report. I've opened the same MAUI project with Visual Studio 2022 (with Roslynator extension) and to my surprise the issues are reported.

Any idea what might going wrong ?

[josefpihrt]

Can you please do the following steps and let me know if it helps?

• Set dotnet.server.useOmnisharp to true
• Disable C# Dev Kit

Related issue: dotnet/vscode-csharp#6790

[Merichbier]

Thanks for the support and help !

For the MAUI project, it indeeds help:

In the unity project however this doesn't work. I guess this is because unity is not using standard .Net but Mono framework.
In any case a solution which would allow C# Dev Kit to stay enabled is preferable as both Unity and MAUI package for VS Code depends on it.

[bdovaz]

The solution to all the problems as I said is that Roslynator would depend on 3.8 and not on 4.x because Unity is not compatible with it...

But it is @josefpihrt who has to evaluate how much impact it has to make that downgrade... The Unity developer base is very large, keep that in mind.

If Meziantou has managed it, I don't see why @josefpihrt won't be able to do it.

[josefpihrt]

@bdovaz Do you think you could you download artifacts nuget_packages from #1349, use that nuget in your local nuget feed and let me know if it works in Unity?

[bdovaz]

@josefpihrt great job! It seems to be working properly: