Export auto-scan does not scan (untranspiled) TypeScript packages correctly

[andrew8088]

Environment

Node v21.6.2
typescript@5.4.2
unimport@3.7.1
vite@5.1.6

Reproduction

• clone this repro repo: https://github.com/andrew8088/unimport-ts-bug-repro
• cd into repo
• pnpm i
• cd packages/app
• If you want to regenerate the type definition file:
  • rm unimport.d.ts
  • pnpm dev
  • kill the dev server
• Now, pnpm build
  • you should see several Property '...' does not exist on type ... errors from tsc.

Describe the bug

The package we're auto-importing has these functions:

export function function1<A, B = string>(a: A, b: B) {
  return [a, b];
}

export function function2<C, D>(c: C, d: D) {
  return [c, d];
}

export function function3<E>(e: E, f: E) {
  return [e, f];
}

type F = number;

export function function4(g: F, h: F) {
  return [g, h];
}

The generated unimport.d.ts file looks like this:

export {}
declare global {
  const B: typeof import('common')['B']
  const D: typeof import('common')['D']
  const b: typeof import('common')['b']
  const d: typeof import('common')['d']
  const f: typeof import('common')['f']
  const function1: typeof import('common')['function1']
  const function2: typeof import('common')['function2']
  const function3: typeof import('common')['function3']
  const function4: typeof import('common')['function4']
  const h: typeof import('common')['h']
}

All the exports that are not function* are not actually exported from the package. Looks like this is actually coming from the mlly package, which is expecting to import JS only.

Not sure if this is a bug or not. I'd like to be able to treat other packages within my monorepo as packages (and auto-import them via presets), and not use the dirs option to import them.

Additional context

No response

Logs

$ pnpm tsc
unimport.d.ts:3:36 - error TS2339: Property 'B' does not exist on type 'typeof import("/Users/andrew/code/projects/disco/packages/common/index")'.

3   const B: typeof import('common')['B']
                                     ~~~

unimport.d.ts:4:36 - error TS2339: Property 'D' does not exist on type 'typeof import("/Users/andrew/code/projects/disco/packages/common/index")'.

4   const D: typeof import('common')['D']
                                     ~~~

unimport.d.ts:5:36 - error TS2339: Property 'b' does not exist on type 'typeof import("/Users/andrew/code/projects/disco/packages/common/index")'.

5   const b: typeof import('common')['b']
                                     ~~~

unimport.d.ts:6:36 - error TS2339: Property 'd' does not exist on type 'typeof import("/Users/andrew/code/projects/disco/packages/common/index")'.

6   const d: typeof import('common')['d']
                                     ~~~

unimport.d.ts:7:36 - error TS2339: Property 'f' does not exist on type 'typeof import("/Users/andrew/code/projects/disco/packages/common/index")'.

7   const f: typeof import('common')['f']
                                     ~~~

unimport.d.ts:12:36 - error TS2339: Property 'h' does not exist on type 'typeof import("/Users/andrew/code/projects/disco/packages/common/index")'.

12   const h: typeof import('common')['h']
                                      ~~~


Found 6 errors in the same file, starting at: unimport.d.ts:3