All source generators fail with nested types that are not classes

[Sergio0694]

Describe the bug

The source generator only assumes nested types will all be classes.
It should instead track the type of each nested type, and correclty generate that.

Regression

No, always been broken

Steps to reproduce

Paste the following snippet:

public partial class MyClass
{
    public partial struct NestedStructType
    {
        public partial interface NestedInterfaceType
        {
            [ObservableRecipient]
            public partial class MyViewModel : ObservableValidator
            {
                [ObservableProperty]
                [Required]
                private string? name;

                [ICommand]
                private void MyCommand()
                {
                }
            }
        }
    }
}

This results in the following code:

partial class MyClass
{
    partial class NestedStructType
    {
        partial class NestedInterfaceType
        {
            partial class MyViewModel
            {
                // Code here...
            }
        }
    }
}

Expected behavior

The generated code would use the appropriate type for each nested type.

IDE and version

VS 2022

IDE version

17.1

Nuget packages

• CommunityToolkit.Common
• CommunityToolkit.Diagnostics
• CommunityToolkit.HighPerformance
• CommunityToolkit.Mvvm (aka MVVM Toolkit)

Nuget package version(s)

main