Source generator ignores class constructor arguments for a [GenerateGenericTest] generic method (CS7036) #7368

What happens

A generic test method compiles to broken code when its class takes constructor arguments from a class-level data source, if the method's type argument is fixed with [GenerateGenericTest]. The source generator emits __CreateInstance_0 as new TestClass() and ignores args, so the build fails with CS7036.

public sealed class ServiceDependencyInjectionAttribute : DependencyInjectionDataSourceAttribute<MyScope> { /* ... */ }

[ServiceDependencyInjection]
public class GenericMethodWithClassArgsTests(MyService service)
{
    public static IEnumerable<object> Rows() => [1];

    [Test]
    [GenerateGenericTest(typeof(int))]
    [MethodDataSource(nameof(Rows))]
    public async Task Run<T>(T value) => await Assert.That(service).IsNotNull();
}

TUnit_..._GenericMethodWithClassArgsTests_Run__T.g.cs(31,20): error CS7036: There is no argument given that corresponds to the required parameter 'service' of 'GenericMethodWithClassArgsTests.GenericMethodWithClassArgsTests(MyService)'

Generated code (net10.0, TUnit.Core.SourceGenerator, TestMetadataGenerator):

private static global::...GenericMethodWithClassArgsTests __CreateInstance_0(global::System.Type[] typeArgs, object?[] args)
{
    return new global::...GenericMethodWithClassArgsTests();
}

Where

Found while adding a regression test to #7328, at tests/TUnit.TestProject/Bugs/_7205 (the test was dropped). The instance factory for a generic method's concrete instantiation is written in src/TUnit.Core.SourceGenerator/Generators/TestMetadataGenerator.cs.

Expected

__CreateInstance_0 passes args to the constructor, as the non-generic __CreateInstance does (for example TUnit_TestProject_Bugs__7205_FailedRowScopeTests__TestSource.g.cs). Reflection mode should be checked too: it builds this class without a compile error, but whether it passes the arguments is unverified.

Acceptance criteria

• A generic method fixed by [GenerateGenericTest] on a non-generic class with constructor data compiles and receives every constructor argument.
• A targeted fixture passes in source-generated and reflection modes, asserting constructor and method values.
• Add and review a generator snapshot that checks the concrete instance factory uses args.

Current-main evidence: TryAddInstantiation sets HasParameterizedConstructor only inside if (testMethod.IsGenericType); EmitConcreteInstanceCreation falls back to parameterless new for the non-generic class/generic-method combination.