Jest test runner fails when trying to test ajax.fetch module

[seanttaylor]

The following unit test:

import ajax from '../../src/sandbox-controller/ajax/index.js';

const { fetch } = ajax;

/**
 * This test suite verfies the the custom {Fetch} interface. (Actual network fetching will be covered in an integration test.)
 */
describe('Ajax', () => {
    test('Should be able to take a configuration for an HTTP request', async () => {
        const data = await fetch({ url: 'http://httpbin.org/json' });
        console.log({ data });
        expect(data).toBeTruthy();
    });
});

fails with the error messsage:

 /workspaces/sandbox-poc/node_modules/node-fetch/src/index.js:9
    import http from 'node:http';
    ^^^^^^

    SyntaxError: Cannot use import statement outside a module

[seanttaylor]

Looks like any test that covers node-fetch fails with the same error above ☝️

[seanttaylor]

Okay. This is a known issue with the latest versions of Jest not supporting ES modules. See here.

[seanttaylor]

Ended up downgrading to the previous major node-fetch version 2.6.1. This fixed the issue.