Files
frontend-app-learner-dashboard/src/ExperimentContext.test.jsx

124 lines
3.7 KiB
JavaScript

import React from 'react';
import { mount } from 'enzyme';
import { waitFor } from '@testing-library/react';
import { useWindowSize } from '@edx/paragon';
import api from 'widgets/ProductRecommendations/api';
import { MockUseState } from 'testUtils';
import * as experiment from 'ExperimentContext';
const state = new MockUseState(experiment);
jest.unmock('react');
jest.spyOn(React, 'useEffect').mockImplementation((cb, prereqs) => ({ useEffect: { cb, prereqs } }));
jest.mock('widgets/ProductRecommendations/api', () => ({
fetchRecommendationsContext: jest.fn(),
}));
describe('experiments context', () => {
beforeEach(() => {
jest.resetAllMocks();
});
describe('useCountryCode', () => {
describe('behaviour', () => {
describe('useEffect call', () => {
let calls;
let cb;
const setCountryCode = jest.fn();
const successfulFetch = { data: { countryCode: 'ZA' } };
beforeEach(() => {
experiment.useCountryCode(setCountryCode);
({ calls } = React.useEffect.mock);
[[cb]] = calls;
});
it('calls useEffect once', () => {
expect(calls.length).toEqual(1);
});
describe('successfull fetch', () => {
it('sets the country code', async () => {
let resolveFn;
api.fetchRecommendationsContext.mockReturnValueOnce(
new Promise((resolve) => {
resolveFn = resolve;
}),
);
cb();
expect(api.fetchRecommendationsContext).toHaveBeenCalled();
expect(setCountryCode).not.toHaveBeenCalled();
resolveFn(successfulFetch);
await waitFor(() => {
expect(setCountryCode).toHaveBeenCalledWith(successfulFetch.data.countryCode);
});
});
});
describe('unsuccessfull fetch', () => {
it('sets the country code to an empty string', async () => {
let rejectFn;
api.fetchRecommendationsContext.mockReturnValueOnce(
new Promise((resolve, reject) => {
rejectFn = reject;
}),
);
cb();
expect(api.fetchRecommendationsContext).toHaveBeenCalled();
expect(setCountryCode).not.toHaveBeenCalled();
rejectFn();
await waitFor(() => {
expect(setCountryCode).toHaveBeenCalledWith('');
});
});
});
});
});
});
describe('ExperimentProvider', () => {
const { ExperimentProvider } = experiment;
const TestComponent = () => {
const {
experiment: exp,
setExperiment,
countryCode,
setCountryCode,
isMobile,
} = experiment.useExperimentContext();
expect(exp.isExperimentActive).toBeFalsy();
expect(exp.inRecommendationsVariant).toBeTruthy();
expect(countryCode).toBeNull();
expect(isMobile).toBe(false);
expect(setExperiment).toBeDefined();
expect(setCountryCode).toBeDefined();
return (
<div />
);
};
it('allows access to child components with the context stateful values', () => {
const countryCodeSpy = jest.spyOn(experiment, 'useCountryCode').mockImplementationOnce(() => {});
useWindowSize.mockImplementationOnce(() => ({ width: 577, height: 943 }));
state.mock();
mount(
<ExperimentProvider>
<TestComponent />
</ExperimentProvider>,
);
expect(countryCodeSpy).toHaveBeenCalledWith(state.setState.countryCode);
state.expectInitializedWith(state.keys.countryCode, null);
state.expectInitializedWith(state.keys.experiment, { isExperimentActive: false, inRecommendationsVariant: true });
});
});
});