Repro

Runnable repro: https://stackblitz.com/edit/markl-ts-jest-repro-gbovnq?file=README.md

Relevant files:

foo.ts

export default function MyFoo() {
  return 'foo';
}

bar.ts

(async function main() {
  const foo = await import('./foo.js');
  console.log(foo);
})();

tsconfig.json

{
  "extends": ["@tsconfig/node20/tsconfig.json"],
  "include": ["src/**/*"]
}

Actual vs Expected behavior

const foo = await import('../src/foo');
console.log(foo);

This produces the following output:

[Module: null prototype] {
  __esModule: true,
  default: { default: [Function: MyFoo] }
}

Expected behavior is that it produces the following output:

[Module: null prototype] {
  __esModule: true,
  default: [Function: MyFoo]
}

(stackblitz runs on node 18, but this reproduces exactly on LTS (20) as well)

Thanks!