fix: use postinstall hook to run sync instead of prepare

[dominikg]

fixes #4585 and possibly a few others where people had issues with missing aliases

caveat:
this currently does not invoke sync for workspace projects depending on "@sveltejs/kit":"workspace:*" when running pnpm install in kit monorepo.

We could think about keeping prepare in those, but i'm uneasy doing it do avoid it masking issues with postinstall.

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Latest commit: 2a5c4fd

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@sveltejs/kit	Patch

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[Rich-Harris]

Looks like we'll need to do some more setup work for our own CI.

If we move this to postinstall, do we still need to keep svelte-kit sync? Feels like at that point we could just have an internal script that we don't expose via a CLI, since we only really added it for the sake of prepare. The consequence of that is that we don't need a svelte-kit CLI at all — we could move svelte-kit package into a separate package, which would make various things quite a bit easier.

[dominikg]

That's a great idea, not going through the cli script for postinstall could make this easier.

Unfortunately I think we need to keep the sync command in a cli for cases where postinstall isnt run.

[Rich-Harris]

Do we though? The only reason we included sync in the first place was so that people weren't faced with red squigglies in a new project — they can npm i && npm run check and the project will typecheck appropriately, which is handy for CI in some cases. But in any situation where you can run svelte-kit sync manually, you can also run sync via vite dev or vite build. I can't imagine there's a situation where you absolutely need to sync, but can't build, after you've already successfully installed the project

[dominikg]

1. there is npm install --ignore-scripts so postinstall is not guaranteed to be executed.
2. dev and build are a lot heavier than sync alone.
3. i think @dummdidumm and @jasonlyu123 recently discussed that the language server might want to call sync
4. our own repo CI currently fails because postinstall for workspace deps isn't called consistently in a pnpm workspace, which means we'd have to build all project for the lint task.

[Rich-Harris]

this should work, no?

Suggested change

	const cliPath = is_workspace
	? fileURLToPath(new URL('./src/cli.js', import.meta.url))
	: '@sveltejs/kit/dist/cli.js';
	await import(cliPath);
	await import(
	fileURLToPath(new URL(`./${is_workspace ? 'src' : 'dist'}/cli.js`, import.meta.url))
	);

[Rich-Harris]

(otherwise it complains about ./dist/cli.js not being in pkg.exports)

[Rich-Harris]

I'll be honest, I don't understand what any of the new stuff in packages/kit/svelte-kit.js is for. Our CI workflow already ensures that SvelteKit is built, can't we get rid of all the is_workspace stuff?

[Rich-Harris]

merged #5760 so will close this