Enzyme
Enzyme is a JavaScript Testing utility for React that makes it easier to assert, manipulate, and traverse your React Components' output.
Enzyme's API is meant to be intuitive and flexible by mimicking jQuery's API for DOM manipulation and traversal.
Enzyme is unopinionated regarding which test runner or assertion library you use, and should be compatible with all major test runners and assertion libraries out there. The documentation and examples for enzyme use mocha and chai, but you should be able to extrapolate to your framework of choice.
If you are interested in using enzyme with custom assertions and convenience functions for testing your React components, you can consider using:
chai-enzyme
with Mocha/Chai.jasmine-enzyme
with Jasmine.jest-enzyme
with Jest.should-enzyme
for should.js.expect-enzyme
for expect.
Using Enzyme with React Native
Using Enzyme with Tape and AVA
Installation
To get started with enzyme, you can simply install it with npm:
npm i --save-dev enzyme
Enzyme is currently compatible with React 15.x
, React 0.14.x
and React 0.13.x
. In order to
achieve this compatibility, some dependencies cannot be explicitly listed in our package.json
.
If you are using React 0.14
or React <15.5
, in addition to enzyme
, you will have to ensure that
you also have the following npm modules installed if they were not already:
npm i --save-dev react-addons-test-utils react-dom
If you are using React >=15.5
, in addition to enzyme
, you will have to ensure that you also have
the following npm modules installed if they were not already:
npm i --save-dev react-test-renderer react-dom
Basic Usage
Shallow Rendering
import React from 'react';
import { expect } from 'chai';
import { shallow } from 'enzyme';
import sinon from 'sinon';
import MyComponent from './MyComponent';
import Foo from './Foo';
describe('<MyComponent />', () => {
it('renders three <Foo /> components', () => {
const wrapper = shallow(<MyComponent />);
expect(wrapper.find(Foo)).to.have.length(3);
});
it('renders an `.icon-star`', () => {
const wrapper = shallow(<MyComponent />);
expect(wrapper.find('.icon-star')).to.have.length(1);
});
it('renders children when passed in', () => {
const wrapper = shallow(
<MyComponent>
<div className="unique" />
</MyComponent>
);
expect(wrapper.contains(<div className="unique" />)).to.equal(true);
});
it('simulates click events', () => {
const onButtonClick = sinon.spy();
const wrapper = shallow(
<Foo onButtonClick={onButtonClick} />
);
wrapper.find('button').simulate('click');
expect(onButtonClick).to.have.property('callCount', 1);
});
});
Read the full API Documentation
Full DOM Rendering
import React from 'react';
import sinon from 'sinon';
import { expect } from 'chai';
import { mount } from 'enzyme';
import Foo from './Foo';
describe('<Foo />', () => {
it('allows us to set props', () => {
const wrapper = mount(<Foo bar="baz" />);
expect(wrapper.props().bar).to.equal('baz');
wrapper.setProps({ bar: 'foo' });
expect(wrapper.props().bar).to.equal('foo');
});
it('simulates click events', () => {
const onButtonClick = sinon.spy();
const wrapper = mount(
<Foo onButtonClick={onButtonClick} />
);
wrapper.find('button').simulate('click');
expect(onButtonClick).to.have.property('callCount', 1);
});
it('calls componentDidMount', () => {
sinon.spy(Foo.prototype, 'componentDidMount');
const wrapper = mount(<Foo />);
expect(Foo.prototype.componentDidMount).to.have.property('callCount', 1);
Foo.prototype.componentDidMount.restore();
});
});
Read the full API Documentation
Static Rendered Markup
import React from 'react';
import { expect } from 'chai';
import { render } from 'enzyme';
import Foo from './Foo';
describe('<Foo />', () => {
it('renders three `.foo-bar`s', () => {
const wrapper = render(<Foo />);
expect(wrapper.find('.foo-bar').length).to.equal(3);
});
it('renders the title', () => {
const wrapper = render(<Foo title="unique" />);
expect(wrapper.text()).to.contain('unique');
});
});
Read the full API Documentation
Future
Contributing
See the Contributors Guide
In the wild
Organizations and projects using enzyme
can list themselves here.