Jest with ES6 and Typescript

Question

I'm currently trying to test my Express apis with Supertest and Jest however I'm running into a problem that I can't seem to find the answer to.

This is my api.

router.get('/', async (req: Request, res: Response) => {
  const products: ProductType[] = await MongooseModel.find({});
  res.send(products);
});

This is my test suite.

import request from 'supertest';
import products from './products';

describe('GET /', () => {
  it('responds with status 200', async () => {
    const response = await request(products).get('/');
    expect(response.statusCode).toBe(200);
  });
});

And this is my babel.config.js

export const presets = [
  ['@babel/preset-env', { targets: { node: 'current' } }],
  +'@babel/preset-typescript',
  +'@babel/plugin-transform-modules-commonjs',
];

When I try to run the tests, I get this response:

.presets[1] must be a string, object, function

Could anyone please help me figure this headache out?

Thanks!

Answer 1

Remove the meaningless + in your preset. +'@babel/preset-typescript' is a number with its value NaN, which is neither a string, an object nor a function. '@babel/preset-typescript' (and the following one) may be what you want.