The only React.js component test you'll ever need (Enzyme + Chai)

my-component.spec.js

import React from 'react';
import { shallow } from 'enzyme';
import MyComponent from '../src/my-component';

const wrapper = shallow(<MyComponent/>);

describe('(Component) MyComponent', () => {
  it('renders without exploding', () => {
    expect(wrapper).to.have.length(1);
  });
});