TUnit 0.76.0 breaks build

[slang25]

Let me start by saying, I'm not sure this is a TUnit problem, but I'm sharing it anyway because it's at worst interesting 😅

The 0.76.0 update caused our build to fail:
https://github.com/justeattakeaway/LocalSqsSnsMessaging/actions/runs/18791602339/job/53622968450?pr=154

It fails during the csc task, although nothing substantially changed. From what I can tell, something in the AOT updates now causes the source generator to load all transitive dependencies, which now surfaces as a failure if any previously unloaded transitive dependencies aren't strong-name signed.

In this case Aspire.Hosting.Testing brings in KubernetesClient, which isn't strong-name signed. However it wasn't an issue before TUnit 0.76.0.

[slang25]

Ok, I'm getting a bit further with the investigation. It's now adding converter like this where it wasn't before:

internal sealed class AotConverter_54 : IAotConverter
{
    public Type SourceType => typeof(global::k8s.Models.V1alpha1MatchResources);
    public Type TargetType => typeof(global::k8s.Models.V1MatchResources);
    public object? Convert(object? value)
    {
        if (value == null) return null;
        if (value is global::k8s.Models.V1alpha1MatchResources typedValue)
        {
            return (global::k8s.Models.V1MatchResources)typedValue;
        }
        return value; // Return original value if type doesn't match
    }
}

[slang25]

I'm not sure it makes sense for TUnit to skip assemblies that aren't using strong name signing, but that's an option, or perhaps some way to configure TUnit to skip a list of assemblies in the scanning.

[thomhurst]

This is indeed a weird one. Is the issue that that assembly wasn't being loaded before, but now with the aot conversion helper method, it's loading that assembly by referencing types, and then causing a failure when it gets loaded?

[benjaminsampica]

To add on, I'm also seeing this now in 0.76.0 with AotConverter

AotConverters.g.cs(1803,60): Error CS0122 : 'ContentRange' is inaccessible due to its protection level

[slang25]

So ignore my language there where I said "loaded", from what I'm gathering if you have a bunch of transitive references that come via nuget, they are passed to csc, but only when you actually write code that references that assembly it gets added to the outputted assembly reference, and csc will do a bunch of checks to make sure that is sound.

One of those checks is the strong naming thing, which I hate, but is a thing we have to live with.

[slang25]

I read that back and it barely makes sense, but I know what I mean!

[thomhurst]

@benjaminsampica That should be simple enough. I'll filter to just public types.

@slang25 I'll see if I can check from the source generation context if we have strong naming or not. Hopefully we can or I'll need to have a think.

[slang25]

Just continuing to think about this, this should be an error that is safe to ignore on modern .NET, and in fact will no longer be an error in a future SDK release (missed the .NET 10 milestone though)
dotnet/roslyn#80595 (comment)

I'll disable the warning as a fix (I also have TreatWarningsAsErrors on, so it's really just a warning).
There is still merit in being selective over the generated code though, but the problem I'm facing here is safe to ignore.

[thomhurst]

@slang25 does the latest version get rid of those warnings?

[slang25]

Hey @thomhurst, yes the new filtering means that the AOT converters generated file is now empty, so this resolves it. I've closed this issue because my original compliant wasn't valid, I had warnings as errors, and this warning shouldn't even be a warning.

But it's good to see that TUnit is being more selective about what code it generates, particularly when it's aimed at AOT scenarios, where you typically want to minimize the types reached.

[Peter-B-]

Just as a reference for others: I saw this issue when adding WireMock.Net, but updating TUnit to 77.0 fixed it.

The build errors read

1>D:\Projects\Temp\TUnitTest\obj\Debug\net9.0\TUnit.Core.SourceGenerator\TUnit.Core.SourceGenerator.Generators.AotConverterGenerator\AotConverters.g.cs(1438,54,1438,55): error CS1001: Identifier expected
1>D:\Projects\Temp\TUnitTest\obj\Debug\net9.0\TUnit.Core.SourceGenerator\TUnit.Core.SourceGenerator.Generators.AotConverterGenerator\AotConverters.g.cs(1438,54,1438,55): error CS1026: ) expected
1>D:\Projects\Temp\TUnitTest\obj\Debug\net9.0\TUnit.Core.SourceGenerator\TUnit.Core.SourceGenerator.Generators.AotConverterGenerator\AotConverters.g.cs(1438,57,1438,63): error CS1002: ; expected
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