CA1515: false positive with delegates

[pcf0]

Analyzer

Diagnostic ID: CA1515: Consider making public types internal

Analyzer source

SDK: Built-in CA analyzers in .NET 9 SDK or later

Version: SDK 9.0.100-rc.2.24474.11

OR

NuGet Package: Microsoft.CodeAnalysis.NetAnalyzers

Version: 9.0.0-preview.24454.1

Describe the bug

A public delegate is defined within an internal class. CA1859 is generated for the delegate.

Steps To Reproduce

1. Create an executable project, e.g. a console project.
2. Create a internal class with a public delegate

internal class Class1
{
    public delegate void SomeDelegate();
}

Expected behavior

No errors reported

Actual behavior

Error reported:
Class1.cs(3,26): error CA1515: Because an application's API isn't typically referenced from outside the assembly, types can be made internal (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1515)

Additional context

[invino4]

This false positive seems to happen for any public nested type of an otherwise internal type. The analyzer SHOULD be checking if the target type is "effectively public" rather than marked public.

[Thomas-Shephard]

I did create a merge request that checks if the type/delegate/enum is externally accessible instead of public.

However, from reading through the docs it isn't quite clear whether this is intended but some of the tests for this functionality imply that it is intended...