Automating Regression Testing: A Complete Guide To How And Why You Should Do It

When you develop a software product, you want it to perform well for every user. To achieve that, you employ various testing techniques before the release. However, good software is often a work in progress, meaning that new functionality is regularly added to the application to help it keep up with the user expectations and market demands.

Regression testing is one of the key ways to ensure that the updated software product still performs as expected. Manual regression testing techniques give you an opportunity to evaluate the app’s performance after a significant change in the code, but more and more businesses are now going for regression test automation as the more thorough, reliable, and budget-friendly alternative to manual testing. 

In fact, 78% of businesses now prefer to automate their regression testing processes. Today we will tell you about the specifics of automated regression tests, their benefits, and possible roadblocks, as well as how to set up automated regression testing with maximum efficiency.

What Is Regression Testing?

Regression testing is the process of making sure that the application’s functionality has not regressed after a change in the code has taken place. There are teams that only perform regression testing after major updates to the code, such as the rollout of new functionality. However, in order to maintain the performance of the app on the desired level, regression testing should take place every time after there has been a change in the code — for example, after fixing a bug.

Why regression testing is important

By the most popular definition, regression means going back to the previous state. However, when it comes to software development or testing, regression means making the product lose some of its functionality or quality due to recent changes in code. When you are working hard to develop and unveil new features or simply improve your software product, regression is the last thing you want to happen.

According to one study, regression testing helps save up to 60% of the time spent on fixing the bugs in software and close to 40% of the money that this process normally requires. With the help of continuous regression testing, you can avoid sudden drops in your product’s quality and, as a result, losing the trust of your customers.

Regression testing vs. smoke testing

Since regression testing and smoke testing are the two types of testing performed on a newly developed build of a product, they are often imagined as interchangeable techniques. However, there are some considerable differences between the two. 

Most importantly, smoke testing is the initial verification of the stability of the build. Regression testing, on the other hand, is a much deeper analysis of the app’s performance. Smoke testing should always be followed by regression testing, and while smoke testing is typically performed by the developers, regression testing should always be done by QA engineers.

Regression testing vs. functional testing

Both functional testing and regression testing are performed to assess the functionality of a software product, which is why they are sometimes united into one testing method. Still, these two types of testing cannot be used interchangeably, as they allow you to achieve different things.

Functional testing deals with the complete functionality of the application, is typically used after the product is developed, and frequently includes black-box testing to make sure that every requirement is met. Regression testing is used to make sure that the functionality of the product has not been negatively affected by the recent updates.

Regression testing vs. unit testing

Both regression testing and unit testing are used to evaluate the introduction of new features, or units, that were added to the product. These two types of testing have similar goals — to ensure that the performance of the application has not been altered by the changes in the code — but the timeframe, techniques, and scale of the testing are very different.

Unit testing normally takes place after the unit has been added to the application but before the deployment of the product. Regression testing can be done both before and after the deployment. Moreover, the goal of unit testing is to see how well the components of the app interact with each other, while regression testing deals with the big picture and whether the deployment of new features has triggered old or new bugs.

Types of Regression Testing

An effective regression testing strategy is a combination of multiple tools and methodologies. There are several types of regression that serve different purposes and should be used in different situations. Here are the 5 types of regression testing that are commonly used by experienced QA engineers.

Progressive regression testing

Progressive regression testing is the essence of regression testing itself: it allows the team to see how the updates to the code affect the application and its performance. Progressive testing can be done after both minor and major changes in the product and requires the development of new test cases.

Unit regression testing

Unit regression testing is, in a way, similar to regular unit testing — both of these testing methods focus on coding units. However, as we’ve mentioned earlier in our article, unit testing is more focused on the way different units interact with each other. Unit regression testing allows making sure that a newly developed coding unit adds value to the product and does not disrupt its performance.

Selective regression testing

Selective regression testing is used to evaluate the effect of a newly designed piece of code on the overall application. One of the biggest benefits of selective regression testing is that it employs the already existing test cases. As a result, you get to perform thorough testing while saving time on developing new test cases.

Retest-all regression testing

When you want to be as thorough as possible with testing a software product, a retest-all regression testing strategy is the one to consider. Under this testing method, the team will retest every aspect of the application and use every existing test case. The obvious downside of this method is that retesting everything is the most resource-intensive type of regression testing, so it’s not the best option for testing small changes to the code.

Corrective regression testing

Unlike most types of regression tests we’ve talked about today, corrective regression testing does not require any changes to be introduced to the original product before the start of the testing process. Corrective regression testing also allows the team to reuse existing test cases to save time on designing new ones.

What Is Automated Regression Testing?

Before we can move on to the specifics of automated regression testing, let’s start with the definition. Automated regression testing is a technique that allows QA engineers to thoroughly test a software product after it has undergone any kind of changes. Regression testing automation utilizes test scripts, plans, and workflow to speed up the process and make it more effective.

In a way, automated regression testing is similar to manual regression testing — both of these testing methods are intended to discover potential bugs that either reappeared after a change was introduced to the software or were brought on by the change itself. However, automation regression testing has a wider scope of testing compared to manual regression testing and can also test the core logic, workflow, and other aspects of a software product.

When does your product need automated regression testing?

Regression test automation is a growing trend in the software industry, but not all regression tests need to be automated. These are the three signs that your automated regression testing is a good option for your product.

1. You frequently update the product. If you regularly develop and roll out new features in your application, running the same tests time after time to manually check for existing and new bugs can be a tedious task. Automation can help you with that.
2. There is a lot of legacy code. If the core code of your software product remains the same throughout multiple updates and you want to ensure its smooth performance without performing time-consuming manual regression testing, automation is the way to go.
3. You want a good ROI. In the long run, automating regression testing will positively influence your ROI, especially if you opt for offshore regression testing outsourcing that will save you both time and money.

Why Should You Automate Regression Testing?

At first glance, automating regression testing looks like a lot of work and additional resources that need to be invested in the process to make it successful. And while setting up the regression test automation practices does require the team to put in extra effort, the benefits of automated regression testing are too strong to ignore. These are the 5 reasons why regression testing automation is exactly what your software development venture needs.

Comprehensive test coverage

Manual regression testing can be very effective in certain situations, but it also has its limitations. Namely, testers often avoid making their manual scripts too deep because they require a lot of resources to be completed. With automated regression testing, the engineer can spend time writing the test script, while the script itself can then be run as many times as needed with minimal time investments. As a result, the tests become more thorough and effective.

Non-stop testing

Manual testers have a certain work schedule, and even if they spend 8 or 10 hours of their day performing regression testing, they can only cover so much during the workday. A big benefit of regression testing automation is that once the tests are written, they can be run 24/7. The team can spend their time more efficiently: for example, dedicate most of their working hours to composing the most effective regression test scripts or set up the tests to run at night automatically, and then simply review the results the next day.

Repeatability and scalability

Building a comprehensive automated regression testing suite is definitely one of the most labor-intensive steps in automating the testing process, but the payoff is absolutely worth it. Once you have a set of test scripts, you can not only adjust them when your project’s needs increase, but also use them on other software products you want to test for possible regressions. Moreover, you can repeatedly test the same application using the same test suite no matter how many iterations it goes through.

Easier maintenance

With every new feature added to the product triggering in-depth regression testing, the test suite will continue to grow. Eventually, as long as the product stays in the active development phase, it will reach the point where the team cannot feasibly maintain it without losing their focus. Regression test automation tools allow the engineers to keep track of the product’s changing needs and adjust the test suite without a major overhaul. Maintaining an existing test suite is also easier when you are dealing with automated regression testing.

Faster product delivery

A well-developed automated regression test suite can help you quickly and effectively test the product after each new feature is deployed, thus shortening the time between the addition of a new feature and the release of the product. Regression testing automation also gives you immediate feedback, so you can learn about the potential issues with your product, take appropriate action, and resolve the issues faster than you would do by only using manual regression testing.

How to Automate Regression Testing in Your Project in 10 Steps

1. Identify the changes in the software

At this stage of the process, you need to identify the changes made in the software, as well as their anticipated effect and how much they affect the overall application. There is no change too small to run automated regression tests, but you need to know the extent of the changes brought to the application by the new additions to the code to select the most appropriate strategy and tools.

2. Design the strategy

There are certain ways in which applications are tested for regressions, but there isn’t a universal, one-size-fits-all approach to automated regression testing. Each case is unique and requires different tools and methodologies to achieve the desired results. Ideally, your testing strategy should be designed by someone with plenty of automated regression testing experience — a solid strategy will help you avoid many of the possible pitfalls.

3. Make sure you have enough resources

There are three primary types of resources you will need to successfully launch your automated testing process. Those resources are:

• Time. This is by far the most crucial resource needed to perform regression testing. When you want to bring the product to market, you need to work as quickly as possible. Your reasoning can be different: some software developers want to get an edge over the competition, while others have obligations to their investors. The key thing here is that you don’t want to rush the process and skip certain issues as a result, which means you need to have enough time for testing and retesting.
• Equipment and tools. Unlike compatibility or mobile testing, regression testing does not require a range of devices to be effective. However, you will need a selection of automation tools, and since there are so many of them to choose from, you will need the help of someone with plenty of experience.
• People. Automating regression testing does save the QA team a lot of time, but it’s not something that can be run completely independently. You will need people to outline the testing strategy, execute it using the best practices, and implement the results to increase the quality of your software product.

4. Assemble your team

Some business owners try launching the automated regression testing process with just one QA engineer, but this strategy will almost certainly backfire. At the very least, your testing team should consist of two members: a QA lead, who will be responsible for the big picture, and the engineer, who will run the tests and report on them to the team lead. 

However, a team this small will only work for a very small project. The bigger your software product is and the more updates it’s getting, the more your team should grow. For example, you can start by adding another engineer and an industry expert who has substantial experience with the type of service you create.

5. Select the most appropriate test cases

A test case is a roadmap for the QA engineer to check the new version of the software product for regressions. In each automated regression testing strategy, the test cases will be different and will depend on the size, history, and goals of the project. At the very minimum, the test cases for your regression testing strategy should include the areas that are typically affected by bugs, areas that have undergone significant changes due to the new fragments of code, and every area of the product that the end user will interact with.

6. Choose the framework

A vital component in any automated regression testing strategy is the selection of the most appropriate framework, which can include anything from the programming language to the primary and secondary tools to help you along the way. If you already have a well-developed testing framework that has proven to be effective in previous regression tests, you can successfully use it, but in most cases, it will need some tweaking to meet the goals of this particular testing case.

7. Create the test scripts

Automation regression testing is often viewed as a time-saving alternative to manual regression testing. Still, when you plan your automated regression testing strategy, there is at least one time-consuming step — designing the test scripts. Not only do you need to select the most relevant test scripts to get an in-depth understanding of the changes brought to the application, but you also need to update them any time there is a new piece of code added to the product. You can also organize the scripts by importance to make sure the most important ones are given priority.

8. Run the tests

After the often grueling preparation stage, there comes a time when you finally get to execute all the tests you have planned. At this point, you need to make sure that the tests cover every level of the application and give you a complete idea of how the product was affected by the new functionality. While running the tests, you can select the most precise and effective ones and later include them in the final version of your automated regression test suite.

9. Analyze the results

All the planning, preparation, and execution of automated regression tests are done for one reason: to achieve a higher quality of software, detect the bugs or other issues brought by a change in the software, and prevent those bugs from reappearing. This is why, after a significant part of the testing process is over, you need to get to the analysis stage. 

A thorough analysis of the results achieved through automated regression tests will help you understand where your product stands in terms of quality, how prone it is to regressions, and what can be done to optimize the regression testing in the future. Pay special attention to the failed tests — they can give you some very valuable insights, provided that it’s not a case of a false failure. 

10. Document everything

You can already get a thorough understanding of the possible regressions in your project during the testing and analysis stage, but you need to always keep the big picture in mind. Keeping extensive documentation of automated regression tests helps you set up the future testing process faster, avoid the possible mistakes that were made during this testing iteration, and quickly introduce new QA engineers to the way automated regression testing is done at your company should you ever change the team.

Top 10 Best Tools for Automated Regression Tests

The choice of tools for automated regression testing is something that can make or break the QA project. It’s not just the question of which tool is the best fit for the particular type of software or platform you are working with, but also the question of how well the tool can be integrated into the test management system. These are the 10 most popular and comprehensive tools used in regression test automation.

1. TestRail — a solution for effective test case management.
2. TestLink — a test management system for quality assurance.
3. Selenium — an automated testing framework for testing web applications.
4. TestComplete  — a tool for automated UI testing.
5. Appium — an automated testing framework for testing mobile applications.
6. TestDrive — a tool for automated testing of browser applications.
7. TestingWhiz  — an automated testing tool for web and mobile applications.
8. SoapUI — an automated testing tool for web services.
9. TestStack.White — a tool for automated testing of desktop applications.
10. Ranorex — an automated testing tool for desktop, web, and mobile applications.

Automated Regression Testing Best Practices

Automating regression testing is now gaining more recognition among software developers and testers, but it’s in no way a new trend. The leading QA companies have been performing this type of testing for years. As a result, there is now a set of automated regression testing best practices that provide the most efficient and practical way to test a software product. Here are the three most popular ones to consider.

Run the tests on every platform

The variety and complexity of your testing scenario are important for the regression testing to be successful, but you also want to make sure that the bugs won’t suddenly reappear on a platform you skipped while running the tests. To get the most complete idea about the effect of new features on the existing functionality, it’s best to use every available platform and device for testing. Depending on the specifics of the product, you can use different computer hardware, operating systems, browsers, and mobile devices.

Repeat test cases

In order to keep up with the growing demands of a software product, the regression test suite needs to constantly expand to include new scenarios and cases. However, it doesn’t mean that you need to discard the existing cases when new ones appear. When you have one or several tests that have successfully identified bugs and glitches in the past, you definitely want to include these tests in your updated test suite. That way, you can make sure that no old bugs have made their way into the new build.

Keep your regression pack up-to-date and organized

A growing regression testing pack needs to be comprehensive but free of the cases you no longer need. For example, keeping the test cases for the features that no longer exist in the application takes a lot of valuable time and space in your regression test suite. It’s essential to regularly review the regression test pack and get rid of the tests that are no longer relevant. Moreover, you will find it much easier to manage your pack if you categorize the tests in a way that is clear not only for you, but also for everyone who may deal with this pack now or in the future.

Possible Challenges of Regression Test Automation

The decision to automate regression testing promises significant benefits for the quality of your software product and the efficiency of the testing process. However, like most innovations, automated regression tests come with their own set of challenges. They don’t necessarily take place all at once in every regression testing journey and you may only experience one or two of them or none at all. Still, it’s important to begin your automated regression testing procedure with the knowledge of what can happen. Here are the challenges you are most likely to encounter along the way.

Growing test suites

You may develop an all-encompassing regression test suite and genuinely believe that it solves all of your problems, but even the most successful test suite doesn’t last forever. As the product and the market around it change, you need to constantly upgrade your regression testing suite. Developing a project for years means watching your test suite grow, and it’s not very often that you can scale it down because you remove certain features from the product.

Test suite maintenance

This challenge of automated regression testing is the direct result of the previous challenge. The bigger your testing suite is, the harder it is to maintain the suite in a way that is easy to navigate and to scale up or down when needed. This proves to be especially important when you switch teams who work on your project and they can hardly make use of the existing test suite because of poor maintenance. This is why choosing a great team with plenty of knowledge about test suite maintenance from the start is instrumental for the success of the project.

Brittle tests

Creating a strong automated regression test, let alone a testing suite, is something that only a highly skilled and experienced QA engineer can achieve. When a test is developed by a person without the necessary experience, it risks becoming brittle — meaning it can deliver false-positive results or fail when you fully expect it to pass. You subsequently waste time, money, and human resources on fixing the bugs that weren’t there in the first place or running the tests again to achieve the necessary result.

Striking the balance

In-depth automated regression tests can be very time-consuming, especially when the project grows consistently, and they will require more and more human effort as regression testing progresses. However, regression testing is only one of the many types of tests you need to perform on a regular basis to ensure outstanding product quality. This is why it’s very important to find the right balance between your available resources and the goals you want to achieve.

Increased expenses

Planning, designing, and maintaining a comprehensive automated regression test suite can be a costly endeavor. Repeatedly running the tests and the tests getting more complex will also make you spend more and more money on the testing process over time. At the same time, the decision to limit your spending can negatively affect the testing practices and lead to a drop in product quality. Working with a qualified regression test automation partner can help you optimize your budget.

When Should You Outsource Automated Regression Testing?

So when is it appropriate to outsource your automated regression testing needs? If you are a software developer who wants to achieve a spotless quality of the product, these are the six instances where automated regression testing outsourcing becomes a necessity.

When you don’t have the required resources or skills

Many software development companies have an expert-level staff of developers, but they don’t see a point in keeping an in-house testing department at all times when they only need to perform tests every now and then. Moreover, a company may have a QA engineer or a team, but while they excel at certain types of testing, others, including automated regression testing, can be out of their reach. Outsourcing your automation regression testing needs to a knowledgeable partner can be the ideal solution: you can enhance your team with one or two engineers who have the necessary skillset or even hire an entire QA team for continuous testing.

When you have a small-scale project

Having an in-house QA team sometimes makes sense in the long run since you get to build effective processes and clear communication with the people who work in the same building as you. However, it only provides benefits for medium and large-scale projects that are intended for continuous growth. If your software project is a small and/or a short-term one, you will likely find that assembling an in-house team and keeping them on a payroll isn’t a financially viable option to test a tiny application or even an individual feature.

When you want to work with the experts

A reliable outsourced software team performs automated regression testing on all types of software products day in and day out. You can expect your outsourced team to have plenty of experience with automating regression testing. Having worked with projects of every scale and complexity, an outsourced team will easily find a solution that works for your product. Building a QA department with a similar level of testing proficiency and experience isn’t always possible. Moreover, it is going to require substantial investments, and you cannot ever be sure that your investment will pay off.

When you need to cut costs

We’ve already established that finding, hiring, and training a software testing team is always going to be more expensive than finding a suitable outsourcing partner. However, building a team is not the only way in which outsourcing will eventually prove to be the most money-saving option out there. You also won’t need to purchase and install any expensive equipment or testing software to perform automated regression tests. Moreover, an experienced QA team will discover the problems with the software early on, saving you money on repeating the tests and postponing the release of the product because you are unsure of its quality.

When you want to meet the deadline

The software industry often operates on tight deadlines: if you fail to deliver a high-quality product by a certain deadline, your competitor gets an advantage and can use the time to roll out a product that will take a share of potential customers from you. To prevent that from happening, you can outsource your automated regression testing needs to a trusted partner. A software outsourcing company with years of experience and a finely tuned workflow will launch the tests quickly and with maximum efficiency to help you successfully meet even the most challenging deadline.

When you need an independent opinion

Having the same team responsible both for the software development and software testing processes in your company can lead to bias. When your QA team has direct knowledge of how the product was developed, they can overlook certain things, which will lead to undiscovered bugs and other issues with the software. Outsourcing your automated regression testing needs means you get to work with a team that has no experience with your product whatsoever. This will give you a fresh perspective and create a more in-depth testing environment.

Final Thoughts

Introducing automated regression testing into your software development life cycle is a move that will require a certain effort to set it up but can help you save a lot of time and human resources in the long run. Moreover, automating your regression testing processes will allow you to discover the bugs that can sometimes be missed during manual testing. All you need to succeed is a reliable team that will match your testing needs with their expertise to deliver a software product of the highest quality.