Testing global event listener within a React component

window.addEventListener not triggered by Enzyme simulated events

Although many developers working with React consider it an anti-pattern, occasionally, there is the need to listen to an event globally within a React component.

The React Component

In my particular case, I have a React component which renders an entire page of my app and I want to listen when the user hits the Enter key and do something after this event happens.
Therefore, on componentDidMount I register the listener to the global window object and on componentDidUnmount I unregister.

componentDidMount() {
    window.addEventListener('keyup', this.handleKeyUp);
  }
componentWillUnmount() {
    window.removeEventListener('keyup', this.handleKeyUp);
  }
handleKeyUp(event) {
    if (event.key === 'Enter') {
      this.handleEnterKey();
    }
  }

It works perfectly!

The Test

I want to provide tests for this functionality and here the trouble comes.
My testing stack includes Enzyme, therefore I think of using the simulate() method to mimic the hit of the Enter key. Surprisingly tho, the event handler is…