The book itself talks a bit about the generalities of testing: how to test, what to test, and what makes a good test. It introduces a simple app which is centered around taking notes in markdown and rendering them as HTML. It is similar to the TodoMVC app, but is a bit simpler and more focused.

The middle chapters review the usage and APIs of 3 testing tools: Chai, an assertion library, Mocha, a test runner, and Sinon.JS, a library for test doubles. This is the testing stack that we use at Sprint.ly, so I was familiar with the topics covered. Each of these chapters was a solid overview of each. They contained all of the major features that I use day-to-day, while also introducing a few new ones that I wasn't aware of.

The last chapter is short, but covers setting up PhantomJS, a headless web browser, to run your browser-based tests in an automated fashion. It also discusses the value of continuous integration and automated testing.