`yarn jest` TypeError: xxx.default is not a constructor -- default export not output as expected

[liyuanqiu]

Current Behavior

tsdx yarn test will report error:

TypeError: xxx.default is not a constructor

when import a class created by tsdx and try to instance it.

reproduction:

1. create a lib using tsdx

tsdx create mylib-a

2. modify index.ts to a class

// mylib-a/src/index.ts
export default class MyLibA {}

3. build

yarn build

4. create another lib using tsdx called mylib-b
5. move mylib-a to mylib-b/src/
6. import mylib-a in mylib-b/test/blah.test.ts

import MyLibA from '../src/mylib-a';
// this line is error when `yarn test`
// TypeError: xxx.default is not a constructor
const instance = new MyLibA();

7. yarn test

---

If I don't use default to export class:

export class MyLibA {}

And import like this:

import { MyLibA } from ...;

Everything will be ok, but it is just a workaround.

Expected behavior

Suggested solution(s)

Additional context

Your environment

Software	Version(s)
TSDX	^0.5.6
TypeScript	^3.4.5
Browser	-
npm/Yarn	yarn@1.13.0
Operating System	macOS Mojave version 10.14.4 (18E226)

[liyuanqiu]

So if one npm library created by tsdx wants to use a class imported from another npm library created by tsdx too in it's tests, the tests won't pass.

Sorry my mother tongue is not English, maybe this description is a little bit confusing...

[iamtheworstdev]

@jaredpalmer any chance you'll be looking into this? noticed it's still happening in a personal project I just created, which conerns me because I only heard about TSDX because a customer is trying to run with it.

[liyuanqiu]

@jaredpalmer any chance you'll be looking into this? noticed it's still happening in a personal project I just created, which conerns me because I only heard about TSDX because a customer is trying to run with it.

My solution is NOT to use "Default Exports" and "Hybrid Exports", only to use "Named Exports".

[agilgur5]

Sounds like this was probably a duplicate of #165 , which was fixed by my #327