Godot fails to compile nested recursive namespace names with cryptic error messages

[LouisIngenthron]

Godot version

v4.0.beta5.mono.official [89a33d2]

System information

Windows 10 x64

Issue description

If you add a C# script with nesting namespace lines that use the same name as a higher namespace name, Godot fails to compile, but gives an odd error about Godot.SourceGenerators temporary files instead of the problem file in question.

Steps to reproduce

To reproduce the error, just add the below class to a C# script in a Godot 4 project and then reference that class in any other script and click build:

using Godot;

namespace SpaceA.SpaceB
{
    namespace SpaceA
    {
        public partial class Foo : Node {}
    }
}

Minimal reproduction project

BugReport.zip

[adamscott]

To cite CONTRIBUTING.md

On the contributors' end, recreating a test project from scratch takes valuable time that can be saved by uploading a minimal project.

To speed up our work, please upload a minimal project that isolates and reproduces the issue. This is always the best way for us to fix it. We recommend attaching a ZIP file with the minimal project directly to the bug report, by drag and dropping the file in the GitHub edition field. This ensures the file can remain available for a long period of time. Only use third-party file hosts if your ZIP file isn't accepted by GitHub because it's too large.

We recommend always attaching a minimal reproduction project, even if the issue may seem simple to reproduce manually.

If you've been asked by a maintainer to upload a minimal reproduction project, you must do so within 7 days. Otherwise, your bug report will be closed as it'll be considered too difficult to diagnose.

Please upload a MRP to the issue's description.

[LouisIngenthron]

Updated original post per request.