Add `exports` field to subpackages to align module resolution with the root level `package.json`

• Check if updating to the latest Preact version resolves the issue

Describe the bug While working on https://github.com/vitest-dev/vitest/issues/737 I found that preact/hooks module entry points to cjs package instead of hooks.mjs. Is this intentional?

If I change it to .mjs everything works fine. Usually Vitest doesn’t resolve what is stored in main field, but it is configurable with resolve.mainFields Vite option (this is what Svelte is doing).

So, I guess Vite prioritizes closest package.json resolvings instead of root level package exports.

Might be related: https://github.com/preactjs/preset-vite/issues/52

To Reproduce

Reproduction: https://github.com/molily/vitest-test/tree/preact-and-svelte

1. Install packages
2. Run pnpm run vitest
3. See error, because it imports the wrong preact lib

Expected behavior No error

[rschristian]

I don’t mean inconsistency in that way. I know perfectly well why you have both module and exports.import with different files there. Inconsistency comes when you don’t have the same in your subpackages.

Sorry, I thought you were referring to the previous sentence with that comment:

If it’s correct then why preact references preact/hook/hook.mjs instead of the “correct” module entry?

[sheremet-va]

It’s not “inconsistent” as they’re two different things.

I don’t mean inconsistency in that way. I know perfectly well why you have both module and exports.import with different files there. Inconsistency comes when you don’t have the same in your subpackages.