gitlab-org--gitlab-foss/spec/frontend/helpers/startup_css_helper_spec.js

85 lines
2.3 KiB
JavaScript

import { waitForCSSLoaded } from '~/helpers/startup_css_helper';
describe('waitForCSSLoaded', () => {
let mockedCallback;
beforeEach(() => {
mockedCallback = jest.fn();
});
describe('Promise-like api', () => {
it('can be used with a callback', async () => {
await waitForCSSLoaded(mockedCallback);
expect(mockedCallback).toHaveBeenCalledTimes(1);
});
it('can be used as a promise', async () => {
await waitForCSSLoaded().then(mockedCallback);
expect(mockedCallback).toHaveBeenCalledTimes(1);
});
});
describe('when gon features is not provided', () => {
let originalGon;
beforeEach(() => {
originalGon = window.gon;
window.gon = null;
});
afterEach(() => {
window.gon = originalGon;
});
it('should invoke the action right away', async () => {
const events = waitForCSSLoaded(mockedCallback);
await events;
expect(mockedCallback).toHaveBeenCalledTimes(1);
});
});
describe('with startup css disabled', () => {
gon.features = {
startupCss: false,
};
it('should invoke the action right away', async () => {
const events = waitForCSSLoaded(mockedCallback);
await events;
expect(mockedCallback).toHaveBeenCalledTimes(1);
});
});
describe('with startup css enabled', () => {
gon.features = {
startupCss: true,
};
it('should dispatch CSSLoaded when the assets are cached or already loaded', async () => {
setFixtures(`
<link href="one.css" data-startupcss="loaded">
<link href="two.css" data-startupcss="loaded">
`);
await waitForCSSLoaded(mockedCallback);
expect(mockedCallback).toHaveBeenCalledTimes(1);
});
it('should wait to call CssLoaded until the assets are loaded', async () => {
setFixtures(`
<link href="one.css" data-startupcss="loading">
<link href="two.css" data-startupcss="loading">
`);
const events = waitForCSSLoaded(mockedCallback);
document
.querySelectorAll('[data-startupcss="loading"]')
.forEach((elem) => elem.setAttribute('data-startupcss', 'loaded'));
document.dispatchEvent(new CustomEvent('CSSStartupLinkLoaded'));
await events;
expect(mockedCallback).toHaveBeenCalledTimes(1);
});
});
});