[Bug] css module path with spaces does not work as expected, rspack works by the way

[JounQin]

https://github.com/JounQin/rspack-css-modules-spaces

{
  "@rspack/cli": "^1.1.8",
  "@rspack/core": "^1.1.8",
  "@rsbuild/core": "^1.1.13"
}

When running pnpm dev:rspack, the generated class name is rspack-repro-_src_space_folder_render_module_css-text which works as expected, but for pnpm dev:rsbuild, it's src-space folder-render-module__text-DF713n in html and .src-space\ folder-render-module__text-DF713n in .css file.

And it's not possible to escape spaces into html.

https://stackoverflow.com/questions/50812118/is-it-possible-to-use-the-space-character-in-css-class-names

The original el.classList.add(styles.text) throws:

https://github.com/JounQin/rspack-css-modules-spaces/blob/4d081a81dafb914b63d3800e06cc3bb62032224c/src/render.js#L5

Uncaught (in promise) InvalidCharacterError: Failed to execute 'add' on 'DOMTokenList': The token provided ('src-space folder-render-module__text-DF713n') contains HTML space characters, which are not valid in tokens.
    at Module.render (render.js:6:1)
    at index.js:2:1

[JounQin]

Just find out it's actually css-loader's issue, it can also be reproduced with webpack and rspack:

JounQin/rspack-css-modules-spaces@aba4f74#diff-72c0c573b2c8e6a48f39d5398d801b197415040d87363a982bc57dbc024d3d75R23-R44

I raised webpack-contrib/css-loader#1626

[chenjiahan]

Thanks, as this has been reported to the css-loader repo, I will close the current issue.