fix(analyzer): ignore type-only imports & exports

[buschtoens]

Prevents type-only imports / exports from ending up in the final bundle.

import type { compute } from 'heavy-library';

export async function performHeavyComputation(
  ...args: Parameters<typeof compute>
): Promise<ReturnType<typeof compute>> {
  const { compute } = await import('heavy-library');
  return compute(...args);
}

[ef4]

Thanks for working on this, this will be nice.

[boris-petrov]

Does this fix this issue (i.e. this comment in that issue)?

[ef4]

Yes, I think this would fix that.

[jamescdavis]

Bump. 🙂

[buschtoens]

Alright, sorry that I kept this idling for so long, but I had no clue and time to dig into, why the 4 *-own scenarios were failing, while all other were running successfully. I finally got around to it now!

The issue was that all scenarios, except for *-own, seem to directly or indirectly enable the TypeScript syntax in the babel options. Without the TS syntax enabled, TS constructs like import type ... cannot be parsed, which is obvious in hindsight, but was quite annoying to debug, as there was no apparent syntax error getting thrown. 😅

I've added @babel/plugin-syntax-typescript to the babelOptions in the beforeEach hook via 1440052, which fixes the issue. I don't really know, whether this solution is acceptable / ideal though, or whether I should opt-in to TS somewhere else.
Any pointers would be greatly appreciated!

I've also rebased the PR and it's all working fine now. ✅

Please let me know, whether I should add more tests, or whether I should change the TS syntax opt-in.

[ef4]

Looks great, thanks.