Automated Regression Testing: Everything You Need To Know

 

Regression testing is a specific form of testing which verifies if a specific piece of software suffered regressions after undergoing changes. So automatic regression testing is nothing more than the procedure for automatically verifying that the program hasn't regressed to a prior undesired state.

Ideally, regression testing--whether automated or not--should be done every time a software program is changed in some way, whether by receiving a new feature, an improvement, or even a bug fix.

In today's article, we'll define and clarify what automatic regression testing means. We'll begin with describing exactly what a regression is, how expensive they are for software teams, and the reason you should employ regression testing to avoid them. Since manual regression testing would be equally time consuming and error-prone, we will then proceed to pay for the need for automation, offering advice and tips on how to actually execute the technique for your own teams.

Let's begin!

Automated Regression Testing: Let us Come Up With a Definition What is it, after all?

This section will answer the questions above and much more.

What Exactly Does"Regression" Mean in"Automated Regression Testing"?

The very first step to be able to understand"automatic regression testing" would be to eliminate the"automatic" part, at least for today. First, we need to understand what"X" means, subsequently"Automated X" will be self-evident. Or, in least, easier to grok.

If we would like to understand what"regression testing" means, the first step is to specify"regression." Within this circumstance, is"regression" bad or good? Should we welcome it or dread it? The answer to the questions above is simple. Here, regression means basically the same thing it means in everyday dialogue --to return to a previous condition. So, in the context of program development, we state we've obtained a regression in which our application unintentionally reverted to a former condition.

Why Do We Want Regression Testing?

As we've only defined in the prior section,"regression" means an unintentional reversion to a previous state. However, something really significant was left implicit in the definition: software regression, more often than not, signifies that the application went back to a poor previous state.

Have you ever had the experience of making some existing feature stop functioning after implementing a brand new one? What about that nasty bug returning months after you believed you'd fully eliminated it? All these are cases of regression. The program has regressed to a previous poor state.

Regression Testing Is Essential in Software

The subject of software development is disproportionately prone to regression issues. Each addition or change made by any programmer has the capacity to cause unanticipated problems in regions (allegedly ) irrelevant to the place where it had been done. Any non-trivial software project, maintained by a group with over, say, five people, has an incredibly high number of possible regressions during each launch.

Developers should always remember that all the changes they make, however small, simple, or insignificant that they seem, have the potential to cause surprising side effects. They are able to break functionalities which don't have anything related to all the modifications being made. By performing regression tests, the developer checks that not only does their alter behave as it's supposed to, but also that it plays well with each of the code which was written up till that point.

That's where regression testing comes in handy. Regression testing is merely the implementation (partial or complete ) of a test suite in order to confirm that a given application hasn't returned to a prior undesired state. If manually completed, however, regression testing can be hugely time-consuming and error-prone, which leads us into our next point.

Regression Testing: Why Automate It?

I often state that everything that is automatable ought to be automated. Meaning, if you're able to automate a procedure, then you probably need to do so. If you're able to automate a process but you're doing it manually, I am afraid you are earning money on the table. Chances are the manual process is slow, time-consuming, dull, and error-prone. That implies you are losing money in three or more distinct ways.

For starters, you waste money with well-paid professional performing jobs that could be automatic. Then, there is always the opportunity price. The people who are performing the evaluations could be doing more valuable tasks. Such tasks could have the potential to create way more value. In the end, since the manual procedure is error-prone, then people are bound to make errors, which will result in losses.

Automated Regression Testing: How to Put It Into Practice

Now that we are done defining theories, it's time for some practical advice on ways to really implement regression testing. There's very good news. If you already write some kind of automatic tests for your program --e.g. unit evaluations --then you are already performing regression testing before knowing about it.

Regression testing is not a"new" class of automated tests. It's not an alternative to device tests or integration tests. To the contrary, your automatic tests --unit tests, integration tests, and similar--written from day one in the project can and should act as regression tests. After each new switch to the codebase, simply re-run each of the relevant tests on the suite to ensure they're not neglecting.