File rename errors in Jest Supertest integration tests.

[ComputerCarl]

I am using Jest and Supertest to run integration tests and Jest will exit with an error.

Q:\redacted\portal-api\node_modules\nedb\lib\datastore.js:77
    if (err) { throw err; }
               ^

[Error: EPERM: operation not permitted, rename 'Q:\redacted\portal-api\data\employer.db~' -> 'Q:\redacted\portal-api\data\employer.db'] {
  errno: -4048,
  code: 'EPERM',
  syscall: 'rename',
  path: 'Q:\\redacted\\portal-api\\data\\employer.db~',
  dest: 'Q:\\redacted\\portal-api\\data\\employer.db'
}
npm ERR! Test failed.  See above for more details.

I have multiple tests in multiple files which resemble the following:

const request = require('supertest');
const app = require('../app');

describe('answers profile routes', () => {
    it('info route', done => {
        request(app)
            .post('/app/client/api/profile/info')
            .send({username: "carl@redacted.com"})
            .expect(200, done);
    });
    it('super route', done => {
        request(app)
            .post( '/app/client/api/profile/super')
            .send({username: "carl@redacted.com"})
            .expect(200, done);
    });
});

I tried to run jest test --runInBand as per issue, but does not resolve my issue.

I think the issue may be running multiple instance of the Express app, via supertest(app), but I didn't know whether to open in here, or Supertest.

Edit: the redacted folder path is alphanumeric with dashes only.