The Robert C. Martin Clean Code Collection (Collection)

Not only are learning tests free, they have a positive return on investment. When there are new releases of the third-party package, we run the learning tests to see whether there are behavioral differences.

Now we know how to get a simple console logger initialized, and we can encapsulate that knowledge into our own logger class so that the rest of our application is isolated from the log4j boundary interface.

In learning tests we call the third-party API, as we expect to use it in our application. We’re essentially doing controlled experiments that check our understanding of that API. The tests focus on what we want out of the API.