@appearhere/bloom/components/Animate/Counter.test.js

Appear Here's pattern library and styleguide

import React from 'react';
import { render, findDOMNode } from 'react-dom';

import Counter from './Counter';

it('renders without crashing', () => {
  const div = document.createElement('div');
  render(<Counter startValue={0} endValue={0} />, div);
});

it('transforms the value as expect', () => {
  const div = document.createElement('div');
  let component;
  render(
    <Counter
      ref={c => {
        component = c;
      }}
      startValue={0}
      endValue={0}
      transform={val => `£${val}`}
    />,
    div,
  );

  expect(findDOMNode(component).innerHTML).toBe('£0');
});