redux-devtools/extension/examples/counter/test/components/Counter.spec.js

import expect from 'expect';
import React from 'react';
import TestUtils from 'react-addons-test-utils';
import Counter from '../../components/Counter';

function setup() {
  const actions = {
    increment: expect.createSpy(),
    incrementIfOdd: expect.createSpy(),
    incrementAsync: expect.createSpy(),
    decrement: expect.createSpy(),
  };
  const component = TestUtils.renderIntoDocument(
    <Counter counter={1} {...actions} />
  );
  return {
    component: component,
    actions: actions,
    buttons: TestUtils.scryRenderedDOMComponentsWithTag(component, 'button'),
    p: TestUtils.findRenderedDOMComponentWithTag(component, 'p'),
  };
}

describe('Counter component', () => {
  it('should display count', () => {
    const { p } = setup();
    expect(p.textContent).toMatch(/^Clicked: 1 times/);
  });

  it('first button should call increment', () => {
    const { buttons, actions } = setup();
    TestUtils.Simulate.click(buttons[0]);
    expect(actions.increment).toHaveBeenCalled();
  });

  it('second button should call decrement', () => {
    const { buttons, actions } = setup();
    TestUtils.Simulate.click(buttons[1]);
    expect(actions.decrement).toHaveBeenCalled();
  });

  it('third button should call incrementIfOdd', () => {
    const { buttons, actions } = setup();
    TestUtils.Simulate.click(buttons[2]);
    expect(actions.incrementIfOdd).toHaveBeenCalled();
  });

  it('fourth button should call incrementAsync', () => {
    const { buttons, actions } = setup();
    TestUtils.Simulate.click(buttons[3]);
    expect(actions.incrementAsync).toHaveBeenCalled();
  });
});