Cut a release, given that svelte internals changed?

[fasterthanlime]

Using this plugin and then depending on a version of Svelte newer than 5.17.4 results in runtime exceptions thrown: $.validate_prop_bindings is not a function (Which is correct since, well, it's been removed).

See:

sveltejs/svelte#14946 (comment)

The package.json in the main branch of this repository already depends on a svelte new enough to not cause problems — cutting a new release of vite-plugin-svelte should resolve the problem for every vite user!

[dominikg]

svelte is a peer dependency, users can update their projects without cutting a release here.

updating the svelte peer version would be a breaking change, which i don't think is justified here.

please check the version of svelte in your project and make sure you rebuild local dependencies.

if you believe this is a bug, please provide a minimal reproduction.

[fasterthanlime]

svelte is a peer dependency, users can update their projects without cutting a release here.

Ahhh, I see now.

I still think it's a footgun that doing "npm install @sveltejs/vite-plugin-svelte@latest" without doing "npm update" brings you into bizarro "compiler produces code that no longer works with the current runtime" world but.. I suppose npm would need "peerDevDependencies" to solve that...

(The underlying issue afaict is that since svelte is both a dev dep (for the compiler) and a regular dep (for the runtime, when doing HMR), package managers can resolve to two different versions happily)

[dominikg]

it doesn't. updating vite-plugin-svelte does not mess with your local svelte version and the devDependency is only relevant in this repo here.

[fasterthanlime]

it doesn't. updating vite-plugin-svelte does not mess with your local svelte version and the devDependency is only relevant in this repo here.

From sveltejs/svelte#14946 (comment), I ended up in this situation:

❯ npm ls svelte -a
fasterthanli-me@1.0.0 /Users/amos/bearcove/fasterthanli.me
├─┬ lithkit@1.0.0 -> ./../lithkit
│ └─┬ @sveltejs/vite-plugin-svelte@5.0.3
│   ├─┬ @sveltejs/vite-plugin-svelte-inspector@4.0.1
│   │ └── svelte@5.0.3 deduped
│   └── svelte@5.0.3
└── svelte@5.20.4

This is what I mean. I have JS that imports svelte (as a regular dep), calls mount — and fails because the svelte compiler version pulled by vite-plugin-svelte was different.

I don't know what the main use case for Svelte is. Maybe it's through SvelteKit. Maybe it's trusting the plugin to mount components through an import in the "index.html" root. Maybe I'm the only person who's calling the mount function manually 🤷

Even if it's a pretty rare scenario, it would be nice to have some sort of ABI field so the generated code (compiled svelte components) can tell you to upgrade your runtime if it's incompatible instead of running into obscure exception.

[paoloricciuti]

Is lith kit your own package? It seems the weird dependency it's there. Also if you are working in a mono repo it could be simply an issue with pnpm having different locks for the different projects

[fasterthanlime]

Also if you are working in a mono repo it could be simply an issue with pnpm having different locks for the different projects

Could be! And yes lithkit is mine. And it's a file dependency, as in:

{
  "dependencies": {
        "lithkit": "file:../lithkit",
  }
}

[paoloricciuti]

How's lith kit package.json looks like?

[fasterthanlime]

How's lith kit package.json looks like?

Now, like this:

{
  "name": "lithkit",
  "version": "1.0.0",
  "description": "Base svelte and TypeScript code for lith applications",
  "type": "module",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "build": "vite build"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "diff": "^7.0.0"
  },
  "devDependencies": {
    "@iconify-json/mdi": "^1.2.3",
    "@iconify/json": "^2.2.310",
    "@iconify/types": "^2.0.0",
    "@sveltejs/vite-plugin-svelte": "^5.0.3",
    "@tsconfig/svelte": "^5.0.4",
    "@types/diff": "^7.0.1",
    "@types/node": "^22.13.5",
    "typescript": "^5.7.3",
    "unplugin-icons": "^22.1.0",
    "vite": "^6.2.0",
    "vite-plugin-top-level-await": "^1.5.0",
    "vite-plugin-wasm": "^3.4.1"
  }
}

And the full fasterthanli.me package.json:

{
  "name": "fasterthanli-me",
  "version": "1.0.0",
  "description": "Frontend for fasterthanli.me, the video player, etc.",
  "type": "module",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "build": "vite build",
    "watch": "vite build --watch",
    "serve": "vite serve --clearScreen false"
  },
  "author": "Amos Wenger <amoswenger@gmail.com>",
  "devDependencies": {
    "@iconify-json/carbon": "^1.2.7",
    "@iconify-json/material-symbols": "^1.2.14",
    "@iconify-json/mdi": "^1.2.3",
    "@iconify-json/mingcute": "^1.2.3",
    "@tsconfig/svelte": "^5.0.4",
    "typescript": "^5.7.3",
    "unplugin-icons": "^22.1.0",
    "vite": "^6.2.0"
  },
  "dependencies": {
    "@bearcove/pulldown-latex-wasm": "^0.1.7",
    "date-fns": "^4.1.0",
    "js-simple-cookie": "^1.3.0",
    "lithkit": "file:../lithkit",
    "mathjs": "^14.2.1",
    "svelte": "^5.20.4",
    "svelte-loading-spinners": "^0.3.6"
  }
}

So yeah, one of the sveltes is pulled in by lithkit as a dev dependency and the other one is pulled by fasterthanli.me as a regular dependency — I'm not familiar with the exact resolution rules for NPM, but I reckon it might be enough.

[dominikg]

the issues section of this repo is not the right place to discuss setup issues with your project. please use https://svelte.dev/chat #questions-svelte-and-kit or https://github.com/sveltejs/svelte/discussions to post a question/help requestes. please make sure to include a link to a repository that shows your setup accurately.

[fasterthanlime]

the issues section of this repo is not the right place to discuss setup issues with your project.

A member of the sveltejs org asked me additional info and I provided it, that’s all that happened. I closed the issue myself and don’t expect further help with it.

There is an actionable issue here by the way (making sure the runtime is compatible with the version of the compiler used) but nobody seems interested in picking it up 🤷

[dominikg]

svelte has no abi or stable runtime apis, you must use the exact same version of svelte to compile and run your app.
If you want to build svelte libraries that are consumed by your app, they should be packaged without compiling and the application that imports them is going to compile at build time with its version of svelte, ensuring compiler and runtime match exactly.

You can read more on packaging here: https://svelte.dev/docs/kit/packaging