SvelteKit 1.0.0-next.202 / Vite 2.7 issue

[techniq]

After upgrading to SvelteKit 1.0.0-next.202 which includes Vite 2.7, I receive the following when importing LayerCake:

10:36:36 PM [vite] Error when evaluating SSR module /src/lib/components/Chart.svelte:
TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".svelte" for /Users/techniq/Documents/Development/open-source/layerchart/node_modules/layercake/src/LayerCake.svelte
    at new NodeError (node:internal/errors:371:5)
    at Object.file: (node:internal/modules/esm/get_format:72:15)
    at defaultGetFormat (node:internal/modules/esm/get_format:85:38)
    at defaultLoad (node:internal/modules/esm/load:13:42)
    at ESMLoader.load (node:internal/modules/esm/loader:303:26)
    at ESMLoader.moduleProvider (node:internal/modules/esm/loader:230:58)
    at new ModuleJob (node:internal/modules/esm/module_job:63:26)
    at ESMLoader.getModuleJob (node:internal/modules/esm/loader:244:11)
    at async ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:78:21)
    at async Promise.all (index 0)

While I'm not 100% certain, I believe the heuristic changed with Vite 2.7 to detect a svelte package, and the best tell now is to include a svelte property in package.json (along with main/exports). If using SvelteKit to build packages, running svelte-kit package now sets this for you. This PR along with the associated issue and code provides some additional info.

Sending a PR your way...

[mhkeller]

Interestingly, I get this same error when using the new sveltekit version even though it has "svelte": "./index.js" in its package.json. I think I have to do some more configuration around exports though because it's currently exporting too much.

[techniq]

Hmm. It’s currently working for me and published/deployed an update to LayerChart with it. I know on my primary application I had layercake in optimizeDeps within svelte.config.js which was still giving me the error (or similar) until I removed it, although I don’t see that in your kit branch at all.

I was just calling it a night (typing on my phone) but if you’re still having issues I can take a look tomorrow sometime.

[mhkeller]

Nope not urgent and it seems to be working now. My next step is to see if it works with the layercake.graphics examples but that will be for another day.