React Testing: Event handlers in React Shallow Rendering unit tests

Background

I am trying to learn how to use the React Shallow Rendering TestUtil and had the tests passing until I added an onClick event handler to both; It seems that there must be some difference with the Accordion.toggle function I am trying to use in Accordion.test.js vs this.toggle in Accordian.js...but I can't figure it out.

Question

How can I get the two highlighted tests in Accordian.test.js to pass?

Steps to reproduce

1. Clone http://ift.tt/1imBOoY
2. npm install
3. npm run dev - see that component is working when you click "Lorem Ipsum"
4. npm run test:watch - see that tests are failing