No checkOnSave diagnostics when opening a file of a project with a running server

[ia0]

I'm wondering if this is expected behavior. The reason I'm asking is because of the difference between:

• Opening a file of a project without a running server. This will start a server and I'll get the checkOnSave diagnostics.
• Opening a file of a project with a running server. This will not show checkOnSave diagnostics. I need to save the file to see them. If I would have opened this file first (when the server was not running), then I would have gotten the diagnostics for this file but not the other.

[ia0]

I believe this might be an eglot bug: joaotavora/eglot#1531.

[ia0]

And also created #20283 as a feature request, since it doesn't seem clear what the standard says, and other LSP servers like clangd behave differently than rust-analyzer.