verbatimModuleSyntax require + clsx not found

[Sheepux]

    "vite": "^5.4.10",
    "svelte": "^5.1.3",
   "svelte-check": "^4.0.5",
   "svelte-preprocess": "^6.0.3",
   "svelte-virtuallists": "^1.3.9",

I just installed the lib via npm (not a fresh project)
And suddently my svelte build is encountering issues

 The TypeScript option verbatimModuleSyntax is now required when using Svelte files with lang="ts". Please add it to your tsconfig.json.

X [ERROR] Could not resolve "clsx"
    ../node_modules/svelte-virtuallists/dist/VirtualListNew.svelte:9:17:
      9 │ import clsx from 'clsx';

  You can mark the path "clsx" as external to exclude it from the bundle, which will remove this
  error and leave the unresolved path in the bundle.

1. To solve clsx i had to declare it as devdependencies in my project
   I still don't know what's the actual issue

2. The verbatim issue is an issue on svelte preprocess part
   Related to Libraries not working with svelte-preprocess v6 sveltejs/svelte-preprocess#643
   Caused by Remove dependency on svelte-preprocess sveltejs/language-tools#2391
   (this could help someone having the issue)
   I removed svelte preprocess (as I was almost not using it) and the issue disapeared

[orefalo]

tks for reporting this issue

interesting...
clsx is the lib I use to build class and styles. I wonder why npm won't bundle it.

[orefalo]

would you have a test project to reproduce the issue.

I am using the library as part of another project https://github.com/orefalo/svelte-treeviews
and it works perfectly

[ronny1982]

It works in your other project because clsx was added as dev dependency in package.json.
Consider adding clsx as dependency or at least as peer dependency in svelte-virtuallists.

[orefalo]

will fix...

Fixed. Thanks for reporting.

now I wonder if I should make it a peer or plain dependency.... and what are +/-

I have the feeling it should be a plain dep

[Sheepux]

fixed by v1.3.10 (closing the issue)

Thanks for the quick response :)

As for the svelte-preprocess issue there were some other solution that i didn't go through:
sveltejs/svelte-preprocess#643 (comment)