Streamlining your testing process

Think about the effort you've put into this book so far. What actions have you been doing the most? Most likely, you've been doing these:

• Switching between src/Appointment.js and test/Appointment.test.js
• Running npm test

To solve the first issue, you should use split-screen functionality in your editor. If you aren't already using that, then take this opportunity to learn how to do it. Load your production module on one side and the corresponding unit test file on the other. Here's a picture of my setup:

You can see that I also have a little test window at the bottom for showing test output.

Jest can also watch your files and auto-run tests when they change. To enable this, change the test command in package.json to jest --watchAll. This reruns all of your tests when it detects any changes.