NetworkError at XMLHttpRequest.send

[Josue Valenica]

Test:

describe('When function authApi its passed', () => {
    test("Authentication services", async () => {
        const user: Response<UserInfo> = await request.get('user');
        // expect(userMock?.lastName).toEqual('Valencia');
        expect(user.payload?.lastName).toEqual('Valencia');

    });
})

The feature:

import ky from 'ky';

const api = ky.extend({
    prefixUrl: '/api/',
    retry: 0,
});
export const request: Request = {
    get: async <R>(url: string) => {
        const res: Response<R> = await api.get(url).json();
        return res;
    },
}

Server configuration

The error

NetworkError
at XMLHttpRequest.send (/Users/project/ui/.yarn/cache/xhr2-npm-0.2.1/node_modules/xhr2/lib/xhr2.js:281:19)
at /Users/project/ui/.yarn/cache/whatwg-fetch-npm-3.6.2/node_modules/whatwg-fetch/dist/fetch.umd.js:600:11
at new Promise (<anonymous>)
at fetch (/Users/project/ui/.yarn/cache/whatwg-fetch-npm-3.6.2/node_modules/whatwg-fetch/dist/fetch.umd.js:507:12)
at /Users/project/ui/.yarn/cache/ky-npm-0.30.0/node_modules/ky/distribution/utils/time.js:11:10
at new Promise (<anonymous>)
at timeout (/Users/project/ui/.yarn/cache/ky-npm-0.30.0/node_modules/ky/distribution/utils/time.js:3:69)
at Ky._fetch (/Users/project/ui/.yarn/cache/ky-npm-0.30.0/node_modules/ky/distribution/core/Ky.js:213:23)
at async fn (/Users/project/ui/.yarn/cache/ky-npm-0.30.0/node_modules/ky/distribution/core/Ky.js:84:28)
at async Promise.result.<computed> [as json] (/Users/project/ui/.yarn/cache/ky-npm-0.30.0/node_modules/ky/distribution/core/Ky.js:120:39)

Why am i importing XMLHttpRequest library:
ReferenceError: XMLHttpRequest is not defined

What could be the issue?

[Artem Zakharchenko]

@josuevalrob, are you using jsdom as Jest environment?

Since newer versions of Jest, its default environment is node now. You need to explicitly install and use jest-environment-jsdom to run browser-like code:

npm i jest-environment-jsdom -D

// your.test.js
/**
 * @jest-environment jsdom
 */

Then XMLHttpRequest will be globally defined by the environment.

The error right now happens not because of third-party libraries but because your testing environment doesn't know what XMLHttpRequest is.

I can also see some interesting jest.config.js setup that I've never seen before. I don't think you can use async functions to create Jest config. It must be a plain object.

[Artem Zakharchenko]

This should be fixed with the new examples. Please give them a try!