Reproduction link or steps

https://github.com/tats-u/tsdown-prop-bug

1. Clone
2. pnpm i
3. node --run build
4. Check the generated files

What is expected?

Only index.{d.ts,js} exist

build:tsup instead of build can get this result

What is actually happening?

Other extra files exist.

They contain abnormally nested references like:

import { __commonJS } from "../../../../../../../../_virtual/rolldown_runtime.js";

Any additional comments?

tsup don't generate such extra files.