Serena Gray

Nov 11, 2021

4 min read

Automated regression testing: All you need to know

Regression testing is a special type of testing that determines if a piece of software has suffered from regressions following changes. Automated regression testing simply means that an application is not returning to a previously undesired condition.

Regression testing should be done whenever a software program is modified in any way.

Today’s post will explain and define automated regression testing. We will explain what a regression is and how expensive it can be for software teams. Finally, we’ll discuss why regression testing should be used to prevent them from happening. Manual regression testing is both tedious and error-prone. We’ll then discuss the need for automation and offer tips and advice on how to implement it for your team.

Automated Testing: Let’s Make a Definition

Before we get into the “how” behind automated regression testing, let’s clarify what it is. What is automated regression testing and why should it be used?

This section answers the above questions and more.

What does “Regression” mean in “Automated-Regression Testing”?

To understand automated regression testing, the first step is to eliminate the “automated” portion. We must first understand what “X” is. Then, “Automated X” will be obvious. It may be even easier to grasp.

To understand “regression testing”, we must first define it. Is it something we should embrace or be afraid of? Answering the above questions is easy. Regression is the same as it is in everyday conversation: to go back to a past state. In software development, we refer to this as a regression if our application accidentally reverts to a previous state.

Why do we need regression testing?

Regression is an unintentional return to a past state, as we have just explained in the previous section. But, there is something more important that was not stated in the definition. Software regression means that the application returned to a poor previous state.

Did you ever experience a bug that made an existing feature not work after it was re-implemented? How about the nasty bug that comes back months later after you think you have eliminated it completely? These are examples of regression . The application has returned to an inferior previous state.

Regression Testing is Vital in Software

Software development is notoriously susceptible to regression issues. Every change or addition made by a developer can cause problems (or omissions) in areas that are not related to the original spot. A non-trivial project that is maintained by more than five people has a high chance of causing regressions in each release.

It is important to remember that developers can cause unexpected side effects from any changes they make, regardless of how simple or straightforward they may seem. Developers can cause functionalities to break that have nothing to do with the changes made. Regression tests are used by developers to verify that the change works as intended.

This is where regression testing comes in. Regression testing is simply the execution of a test suite to ensure that an application doesn’t return to an earlier undesired state. Regression testing, however, can be very time-consuming and error-prone if it is done manually. This leads us to the next point.

Regression Testing: Why Automate it?

Automating everything is a good idea. Automating a process is a good idea. If you are unable to automate a process, but still do it manually , then you might be wasting money . The manual process can be slow, tedious, time-consuming and error-prone. This means you are losing money at least three ways.

First, it is a waste of money to have well-paid professionals performing tasks that could easily be automated. There is always an opportunity cost. People who perform the tests might be performing more valuable tasks. These tasks may have the potential for generating more value. The manual process is also error-prone. This means that people will make mistakes which could lead to losses.

Automated regression testing: How to put it into practice

We’re now ready to discuss practical ways to implement regression testing. Good news! You can write automated tests for your applications, such as unit tests. Unit tests are a form of regression testing.

Regression testing is not an “old” category of automated test. Regression testing is not an alternative to integration or unit tests. Your automated tests (integration tests, unit tests and similar) that you have written from the beginning of the project can and should be used as regression tests. To ensure that they aren’t failing, you can re-run the entire suite of tests after each change to the codebase.

Best Practices in Automated Regression Testing

Regression testing is not your specific implementation. There are best practices that you can follow.

  • Use a Test Management software: This software is essential for any project larger than a single-developer project. Realistically, you will have far more test cases than you can track and manage individually. You have many test management tools available to you.
  • Maintain a Testing Schedule This will ensure that the final product is tested thoroughly. The schedule will also encourage team members to adjust to a regular testing program.
  • Create a new failing test for every bug found: Visualize your code as having an unambiguous, reproducible problem. All of your tests pass. This means either your current tests are incorrect or your test suite lacks tests. To document the bug, create a new failing test if you find yourself in such a situation.
  • Split Your Test Suite into Smaller Categories: Most likely, your test management tool will allow you to categorize all of your tests. This will allow your team to easily identify each type of test.

Automated regression testing: Get it to work for your team ASAP

Software development is an artistic endeavor unlike any other. However, there are many risks along the way to reap its rewards. Writing code can be dangerous because you may break existing functionality and add new features. Even when we fix bugs, older functionality can be brought back to life. Every small, seemingly insignificant change can lead to a terrifying regression.

A suite of regression tests can help you get rid of all kinds of regressions, which you should.