You now have enough understanding of unit tests, Mocha, and working with promises to complete the unit tests for the Create User handler. Have a go at implementing this yourself, referring back to the reference code sample only if you need to.

As always, don't forget to run the unit and E2E tests to make sure you haven't introduced any regression, and then commit the changes to our repository:

$ git add -A && git commit -m "Add unit tests for Create User request handler"