Auto-unmounting React components in Jasmine tests

jasmine_helpers.js

import React from 'react';
import {mountNodes} from 'testing/render_test_utils';

// setup afterEach method to unmount all mounted nodes
jasmine.getEnv().topSuite().afterEach({
  fn: () => {
    while ( mountNodes.length ) {
      let mountNode = mountNodes.pop();
      React.unmountComponentAtNode(mountNode);
    }
  }
});

render_test_utils.js

import React from 'react';
let mountNodes = [];

let render = (component, mountNode) => {
  if (mountNode === undefined) throw new Error('mountNode was undefined');
  mountNodes.push(mountNode);
  return React.render(component, mountNode);
};

let renderIntoDocument = (component) => {
  let mountNode = document.createElement('div');
  return render(component, mountNode);
};
 
export default {
  // expose a reference to allow testing utils to cleanup
  mountNodes,
  renderIntoDocument,
  render
};