Nobody likes doing the same task over and over. Unfortunately, every time your software updates its code, it’s necessary to perform regression testing. Since most software is written to contain multiple interlocking parts, changing one section of code means that other parts are affected as well. Regression testing is necessary to confirm that the new, added code is not negatively affecting any of the sections of code that worked in the previous version.

What is Regression Testing?

Regression testing is when, after a change to your software’s code or environment, you must re-test key elements of the software to make sure that this new change hasn’t affected any other part of the software’s functioning. Regression testing isn’t specific to software testing automation— software should be tested for regression when it’s updated, even if that testing is done manually.

However, the benefit of automating your regression testing is that a script can check that certain functions of the code are still working much faster than your human testers can. If you’re performing the same regression test 500 times, writing an automated script that will perform that regression for you can save you time and money.

When to Perform Regression Tests

Any time your software changes, you should perform a regression test. If you’ve added new code, regression test. If you’ve gone in and fixed a bug, regression test to make sure that “fix” didn’t break something somewhere else. Especially when working with agile development, regression testing is important because your software is being constantly updated. Each of these changes represents a new opportunity for the interlocking code to cause a once-working section to malfunction.

Why Use Automated Regression Testing?

The benefit of automated regression testing is the same benefit of any automated software testing: it gets repetitive tasks done more quickly and frees up your software devs and testers for other, more important work. It can be especially helpful when performing regression testing, which often requires testing that the same bit of code is functioning the same way in multiple scenarios. For example: If your software is an ecommerce website and you want to make sure that the shopping cart link and icon appear on every page.

Instead of performing the same test for every single page on your site, you can instead write an automated script that will perform the regression test for you. It’s important to remember though that, like all automated testing, an automated regression test cannot think for itself. For example, if the website code from our previous example has malfunctioned and the shopping cart link and icon are there, but not in the correct place, the test will still return a positive result. That’s why it’s important to think intelligently when designing your automated regression testing.

Regression Testing When Your Software is Integrated

Sometimes you have to regression test even when it’s not your software that’s changed. If your software references or is integrated with a piece of software coding that was written by someone else, a change in their code will still change the way that it interacts with your software and perhaps even the way your software functions. While most companies offering integration are good about making sure their software remains backward compatible, if you know that your integrated software has updated, it’s probably a good idea to check your own software, too.

Automated regression testing can be a powerful tool in your quality assurance toolkit. However, just like a hammer isn’t great at sawing and a saw isn’t a good hammer, it’s important to make sure you’re not trying to use regression testing when it’s not the right tool for the job. If you keep that in mind and save the automated regression testing for cases where the code is fairly steady and uncomplicated, you’ll find yourself with the perfect tool to save your developers time and assure your software is running smoothly.