jest-worker: should not expose `.default` babel interop

import a from 'jest-worker' of course, works fine, because it’s using babel on both ends.

However, const b = require('jest-worker') results in a !== b, and to get at the proper value, you need to do b.default.

Entry points should not expose babel interop details like .default - can https://github.com/facebook/jest/blob/master/packages/jest-worker/src/index.js use module.exports = instead of export default (or can you use the add-module-exports transform?

[SimenB]

We’re exporting multiple things (which I don’t wanna change), so the babel plugin won’t work. A named export is probably our only option, although it’s a breaking change. Instead of export default class JestWorker we can do export class JestWorker. Possibly name it Worker instead as we don’t need to repeat the package name in the export

[ljharb]

@SimenB i’m pretty sure you could still change things by attaching all the named exports to the default export, and explicitly add __esModule: true, and it wouldn’t be a breaking change - it’d be pretty gross tho, to be sure.