Vite V6 can't resolve alias if css transformer is lightningcss

[kovalchukq]

Describe the bug

I am doing:

I am using Vite v6.0.1 in my project with the lightningcss CSS transformer enabled. My configuration includes custom aliases in vite.config.ts, such as @assets pointing to the assets folder. In my CSS files, I reference assets using this alias, like this:

background-image: url("@assets/vue.svg");

What I expect is:

The alias @assets should resolve to the correct path.

What actually happens is:

When the lightningcss transformer is enabled, Vite fails to resolve the alias @assets in CSS files and Vue style files.

Reproduction

https://stackblitz.com/edit/vitejs-vite-c1vaah?file=src%2Fstyle.css

Steps to reproduce

Run npm run dev

System Info

Windows

Used Package Manager

npm

Logs

[plugin:vite:css-analysis] ENOENT: no such file or directory, open '@assets/vue.svg'
/home/projects/vitejs-vite-c1vaah/src/style.css

Validations

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• The provided reproduction is a minimal reproducible example of the bug.