@sveltejs/package: Assume no svelte 3 if can't read version with semver (pnpm calalog)

[jycouet]

I'm using pnpm and the catalog feature.
It's nice in monorepos to manage deps & version in one place. (+ you can name & group deps)

In package.json:

{
  "peerDependencies": {
    "svelte": "catalog:svelte-dep"
  }  
}

An in pnpm-workspace.yaml

catalogs:
  # adding comment is GREAT!
  svelte-dep:
    'svelte': '^5.0.0'
  
  # this is the stuff bla bla bla
  sveltekit:
    '@sveltejs/kit': '2.17.3'
    '@sveltejs/package': '2.3.7'
    '@sveltejs/vite-plugin-svelte': '5.0.1'
    '@sveltejs/adapter-auto': '4.0.0'
    '@sveltejs/adapter-node': '5.2.12'

BUT, it's not semver standard. :( (Maybe one day?)

That's why I would suggest this fix ?
Feel free to le me know what do you think

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-13553-svelte.vercel.app/

[benmccann]

I don't really know if this is safe. What happens if it is a Svelte 3 app with a pnpm-workspace.yaml and then we assume it's a Svelte 5 app? Perhaps a better solution would be to look for the pnpm-workspace.yaml file and then read it

[jycouet]

You are right, this is not "safe".
If there is a pnpm-workspace.yaml, yes we could check if there is a catalog, ... but needs to be parsed & co. (Not too complicated, but needs to be done). Do you allow having a new dependency for parsing & exploiting this pnpm feature ? Or you would like 1 or 2 functions here directly ?

I'll look at this later :)

[jycouet]

Done with #13850

[dummdidumm]

Oh no, I didn't realize you made a PR many weeks ago for this already - sorry