Error when using enzyme mount function

Hello Guys,

I’m using the enzyme mount function for a test and when i run this test i get this error message: It looks like you called mount() without a global document being loaded

My test

import React from 'react';
import { shallow, mount } from 'enzyme';
import { Layout } from './index';
import ErrorSnackbar from './errorSnackbar';

  it('should render ErrorSnackbar component when error prop is defined', () => {
    const errorStub = { message: chance.sentence() };
    const clearErrorMock = jest.fn();
    const wrapper = mount(
      <Layout loading={chance.bool()} clearError={clearErrorMock} pageTitle={chance.word()} error={errorStub} />
    );

    expect(wrapper.find(ErrorSnackbar).exists()).toBe(true);
    expect(wrapper.find(ErrorSnackbar).props()).error.toBe(errorStub);
    expect(wrapper.find(ErrorSnackbar).props()).clearError.toBe(clearErrorMock);
  })

package.json dev dependencies

"devDependencies": {
    "chance": "^1.0.13",
    "enzyme": "^3.3.0",
    "enzyme-adapter-react-16": "^1.1.1",
    "enzyme-to-json": "^3.3.0",
    "react-test-renderer": "^16.2.0",
    "redux-mock-store": "^1.4.0"
  },

setupTests.js

import { configure } from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';

configure({ adapter: new Adapter() });

[leonardovillela]

If anyone wish to configure WebStorm to run Jest tests with CRA correct, i add the jest option --env=jsdom, in that way the tests runs fine.

WebStorm Jest Config

[gaearon]

The original idea was that jsdom is not really required and we want to nudge people to not depend on it in their tests (eg by using snapshot tests instead). Then they could remove the flag and enjoy faster test boot time.

Writing tests without depending on jsdom takes a bit of training to use correctly so we didn’t include those tests by default with the generated project.

I think we overestimated people’s curiosity. I thought people would try removing it, or at least read the relevant section in the user guide, but in practice everyone just leaves this flag on. It seems like most people don’t complain about test startup time either.

So maybe we should just flip the default to use jsdom.