Regression testing

So far, you’ve been seeing ways of testing if what you’re building is behaving according to expectations. What you’ll see now is a way of checking if any of the previously tested items stopped behaving in the way they were before. Something going from a state of success to a state of failure is known as regression. This type of testing is called regression testing because it detects those situations when something that had been fixed stopped working.

The first thing to pay attention to is the scope of the regression tests. Here, you can limit your tests to anything that has been fixed or you can attempt to test all the existing features. While the former option is easier to set up, maintain, and scale, the latter is more comprehensive and gives you more confidence about the quality of your API. Whatever option you choose, make sure it provides you with the information you’re looking for. For example, if your priority is to make sure...