[BUG] C# build errors are not highlighted

[tedbrownxr]

Describe the Issue

In a C# Console project with known build errors (e.g. multiple errors shown when running "dotnet build"), no errors are shown in VS Code. You can even write random letters anywhere in the file: nothing shows up as a problem.

A reset of the project (removing sln, .vscode and re-opening) did not resolve the issue.
An update of the application and all related extensions did not resolve the issue.

This issue can be reproduced by creating a new project with:

dotnet new console
code .

Using:

• Mac OS 14.1.1
• VS Code 1.100.2
• .NET Install Tool 2.3.5
• C# Extension 2.76.27
• C# Dev Kit 1.19.63

Steps To Reproduce

No response

Expected Behavior

No response

Environment Information

No response

[tedbrownxr]

After reproducing this issue a few times in new projects, I returned to my original project. The situation somewhat resolved:

By selecting a file known to have an error, errors were shown. If a file with known errors was not opened, it would not show as having errors in the Explorer.

This issue appears to be coincide with a syntax highlighting issue that I was also writing a bug on, meaning that classes, methods, and variables were given the same color treatment.

I'm not satisfied with the fact that it "resolved itself" though. Something is broken.

[webreidi]

@tedbrownxr
We have noticed that in some instances, VS Code is not activating the extension or extension activation is delayed. This would cause the issues that you are references, and opening a file would kickstart the activation. When you experience these issues, can you check the status bar to see if the projects have loaded. You'll see "Projects: " in the status bar and it will list a number of projects loaded or will show the name of the project the current open file is in, like the image below.

[tedbrownxr]

Thanks, I'll keep an eye out. Naturally, everything is behaving right now.

Your comment explains another interesting symptom: when I open a project, such as a new project:

• Syntax highlighting works while the "Projects" status bar is loading.
• When the Projects status bar finishes loading, the syntax highlighting stops working (classes have the same color as methods).
• When I click another file (e.g. the csproj file) and back to Program.cs, the syntax highlighting works again.

Before your comment, I could never quite understand what was triggering the "reset" of syntax highlighting. Now I can tell it's clearly something to do with the Project's loading status.

This issue is highly reproducible: you just have to fully exit Visual Studio between sessions, and call code . in the project folder.

[github-actions]

@webreidi, the 'needs-more-info' label has been removed upon receiving further response from the original bug filer.