5 Keys to an Effective Regression Testing Suite

Regression testing has evolved significantly in the last 10 years. Gone are the days when regression testing cycles ran for weeks, if not months, on the same candidate code build. Today, regression testing suites must be lean, effective and efficient.

Regardless of the software development methodology, development teams must turn out quality code at a rapid pace to meet customer demands and keep up with the competition. Regression testing in Agile, for example, might last 1-2 days, though some organizations might have regression testing cycles that last 3-5 days. But what truly matters is that the regression testing suite is effective, not how many days it takes to execute.

Let's discuss regression testing’s importance, and how to create a highly effective and efficient regression test suite.

Why is regression testing important?

Regression testing improves the quality of the application code at the release point. Unless it is continuous, regression testing usually occurs in a time period before the release date. Regression testing proves that new code integrates into the existing codebase without complication. When the application continues to function as it did previously, the regression testing suite is validated and the new release code is deemed safe for distribution to customers.

Ongoing changes tend to break existing code and create defects. The regression testing suite verifies that the customer does not receive defective release code, which can cause a poor user experience and lost revenue.

If you break customers’ trust by releasing flawed applications, it’s very difficult to regain it — or even impossible. Invest in a regression testing suite to ensure a higher quality release code build.

How to create a regression testing suite

There are different ways to create a regression test suite. To maximize effectiveness and efficiency in a short-execution timeline, consider a few options. You can create a regression testing suite using groups, which implement tests that cover the application’s full functionality. You might group regression tests according to features, functions, integrations or another logical area. In this regression testing strategy, you execute a group for each release in a rotation. For example, if you group regression testing cycles into four sets, then you execute one set per release — this would require four releases to go through the full regression test suite. Or, you can simply execute the regression test groups that apply to the most recent release, such as payment functionality when the cart checkout feature is changed.

Alternatively, you might consider continuous testing, in which testing continues onward regardless of release deadlines. The QA testing team performs its work testing new features and bugs, and then executes manual regression testing when possible. Automated regression tests can run whenever is convenient, such as overnight or on weekends — in this case, there is no separate regression testing cycle; the regression test suite continues to be executed.

Whichever method you choose, take these five actions when creating your regression testing suite:

• categorize high-priority tests

• create smoke tests

• mix in some manual tests

• validate integrations

• assess performance

1. Prioritize your regression tests

When developing a regression testing suite, the first key element is to include tests that are critical or high priority. High-priority tests assess the main functions or base workflows of the application. Tests for critical functions might evaluate back-end engines, APIs and database connections or performance. Important workflows might also include UI-based functionality.

First, define your priorities — and what they mean. Then, review all existing functional tests and assign them a priority. If you don’t have existing tests, prioritize as you create them. Develop the critical tests first, and then move down the line. Critical and high-priority tests check for defects that demand rapid fixes. A defect in critical or high-priority functions either prevents the application from functioning at all or results in significant failures in the workflow, costing customers valuable time and money due to lost work or re-work. When these functions fail, there is a direct financial impact to the company, and they require additional resource time to repair.

Consider codeless automation or code-based automated tests for critical functions. Applause Codeless Automation (ACA) can help automate part of your regression test suite to check critical functionality without writing a single line of code. If you execute critical regression tests every time a build is created, you’ll find these types of issues rapidly, before they impact customers, QA testers or developers working to get a release out the door.

2. Build smoke tests

When pulling your critical and high-priority tests into a regression suite, label it the “smoke test suite” and execute it daily, bi-weekly or with every build. Execute the smoke tests before any other testing starts to avoid unnecessary shutdowns and loss of work time.

Automate your smoke tests, with ACA or scripted tests, to save a significant amount of time. If you keep the tests straightforward, say with one or two validation points, it simplifies failure analysis. Don’t test every function with a smoke test; just cover as much of the codebase as possible at a non-superficial level. Why? The value in test automation is finding defects in workflows that occur frequently and are critical to the functionality of your application. Ensure your smoke test suite is succinct and of high value.

Execute these tests frequently and before release, as well as each time the release build changes. It might also make sense to execute some smoke tests in production to verify, for example, a back-end change that shouldn’t directly affect users. If you add bug fixes and last-minute enhancement features to a release in the final stages, you need a smoke test regression suite.

3. Put in some manual effort

Next, create a suite of tests for the basic functionality across the application. Often, these are workflows most automated tools cannot handle due to the integrated and complex interactions involved. While this basic functional regression test suite contains workflows that might not be critical to the application’s function, they are frequently used workflows for end users.

Manual regression tests might include exploratory tests around the test case that automation wouldn’t cover. Other manual regression tests cover end-to-end or system workflows that are long and complex — not a great fit for automation.

Basic functional regression test suites help keep your code clean and generate positive customer responses to your application

4. Test the integrations

Execute a regression suite that tests your API connections, back-end messaging engines and data feeds. Validate any integrated process that the application needs, but the user doesn’t see. Granted, frequently developing a regression test suite for these types of functions is tedious and often requires developer or IT help, but it is well worth the effort.

You don’t have to cover everything. Create tests that assess, or at least touch, each process in a valid way, as in the groups discussed above. Typically, QA testers don’t have direct access to the back-end processes. However, tests must assess these features, even if they seem superficial. When back-end processes, API or data connections fail, it’s quickly obvious to the user. Allow QA testers access to these features, or tools to view and create functional tests in the back end. Invest some developer time if required, it’ll be worth the effort if you stop even one failure from occurring in these business-critical processing engines.

5. Don’t forget performance

Performance testing is a four letter word to most development organizations. Why? If the application works, many consider that to be good enough. But is it?

If the user experience changes in performance with each release, that’s disconcerting to an end user. Worse yet, if the application gets slower each release in key workflow functions, then your customer loses trust in your application. In this case, frustration builds up because the user cannot tell if the system is working or stalled. Excessive waits waste your end users’ time and negatively affect their productivity.

Whether complex or simple, your regression test suite must account for performance testing. Performance will not fix itself, and it will eventually take your application down if you fail to address issues. Many don’t consider the speed of the system a critical feature, but it does significantly affect customer perception of your application. Develop a performance regression suite either with a performance testing tool, or simple manual tests that check for problem areas.

How codeless automation fits in

Regression test cycles can be manual or automated, but are usually a mix of both. The beauty of an effective regression test suite is, once it’s developed, you can run portions or all of it whenever needed. Use your regression testing suite in a flexible manner to meet your business needs. Give your application and software development team the best chance for success and invest in creating an effective and efficient regression testing suite.

Applause Codeless Automation can help you begin to build a regression test suite. Take advantage of ACA to build modular tests for simple workflows that you can adjust and reuse as needed. Additionally, Automated Functional Testing provides access to automation experts and a powerful framework to help you build a comprehensive automated testing suite.