__tests__/test-constants.ts
import { XMLHttpRequest } from '../src/XMLHttpRequest';
test('constants', () => {
const xhr = new XMLHttpRequest();
expect(xhr.UNSENT).toEqual(0);
expect(xhr.OPENED).toEqual(1);
expect(xhr.HEADERS_RECEIVED).toEqual(2);
expect(xhr.LOADING).toEqual(3);
expect(xhr.DONE).toEqual(4);
});