Adding new features or enhancements to an app is a good thing – unless the changes trigger an unexpected problem. To protect against this risk, QA teams and developers can leverage automated regression testing, which offers a fast and efficient means of confirming that software upgrades or changes don't introduce bugs into applications.
From a business perspective, investing in automated regression testing has significant advantages. The scalable nature of this testing approach, coupled with developers creating reusable test scripts, results in long-term cost savings. The proficiency in automated regression testing enhances a company's ability to adapt swiftly to market demands, ensuring the continuous delivery of high-quality software.
If you’re a developer, automated regression testing can help identify and rectify issues early in the development process. Learning this testing approach enables developers to streamline repetitive tasks, saving valuable time and resources that can be redirected toward creativity and feature development.
Want to know more about how automated regression testing works, why it's important, and how to get started automating regression tests? You've come to the right place. The following article explains everything modern development and QA engineers need to know about automated regression testing.
What Is Automated Regression Testing?
Automated regression testing is the use of a test automation framework to run regression tests.
To explain fully what that means, let's also define regression testing. Regression testing is the practice of checking for bugs that are introduced by software updates or upgrades. In other words, regression testing helps you determine whether your software has "regressed" due to changes implemented by developers.
So, when you adopt an automated approach to running regression tests, you are performing automated regression testing.
Why Should You Automate Regression Tests?
Like most types of software tests, it's possible to run regression tests manually or automatically. There is nothing specifically about regression testing that requires engineers to run regression tests automatically.
That said, regression tests are excellent candidates for automation because they typically occur frequently and on a large scale. Whenever developers modify an application – a process that happens very frequently in organizations that adopt continuous delivery strategies, which entail pushing out application updates as frequently as multiple times a day – QA engineers should perform regression tests to ensure that the changes don't trigger unexpected problems.
If they did this manually, the testing process could take hours, days, or even weeks, depending on how many regression tests need to run. The result would be major delays in software delivery, not to mention a very inefficient use of QA engineers' time.
By automating regression testing (and also running the automated tests in parallel, a practice that speeds testing even further), engineers can dramatically reduce both the time and effort required to perform regression tests. In turn, they can help their organizations to deploy software updates and upgrades faster and with lower risk, while also freeing themselves to focus on more productive tasks than running manual regression tests.
Thus, if you have limited resources for automating tests and need to make strategic decisions about which types of tests to automate, regression tests tend to be a good choice. You'll earn a higher ROI, so to speak, from automating regression tests than you would from automating other types of tests that don't occur as frequently or in such high volumes.
Benefits of Automated Regression Testing
By automating regression tests, teams gain the following key benefits:
Increased efficiency: Automated regression tests run faster and require less time and effort on the part of QA engineers. In both respects, they increase the efficiency of testing teams.
Faster release cycles: Automated regression tests help ensure that testing doesn't hold up software release cycles. Users get new features sooner, and developers don't sit idle waiting for their latest set of updates to pass regression testing before they can begin work on the next round of enhancements.
Cost savings: Faster, more efficient tests lead to lower costs because teams can catch and fix bugs with less effort. Automated regression tests help ensure that staff time is used more effectively and that products generate more revenue thanks to having fewer bugs.
Enhanced test coverage: Automated tests help teams run more tests in less time. As a result, they can increase test coverage without increasing the effort they have to invest in testing.
Reduced human error: If you test for regressions manually, there is always a chance that you'll overlook certain regressions due to human error. Automated regression testing eliminates this risk. As long as you configure your automated tests properly, they'll always detect whichever regressions you design them to catch.
In short, automated regression testing leads to better test results with less time and effort – a key benefit for any team striving to ensure that developers can deploy software updates regularly without breaking applications in the process.
How to Automate Regression Testing
The process for automating regression tests is fairly straightforward. Let's walk through the main steps.
1. Determine What and When to Test
It's often not practical to test every possible component of every change to an application. Instead, QA engineers will need to make strategic choices about what to test and how often to run regression tests.
These decisions should be informed by considerations like which features and functionality are most important to an application and should therefore be covered by regression tests. You should also consider how often your developers update applications and what the scope of the updates entails. Small changes may not necessitate regression tests, but any update that significantly changes the code or appearance of an app should typically trigger regression testing.
2. Write Tests
After determining what to test for, write automated regression tests using a test automation framework. For example, here's a sample regression test that uses Selenium and TestNG:
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.testng.annotations.AfterClass;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Test;
public class RegressionTest {
private WebDriver driver;
private String baseUrl = "https://example.com"; // Replace with your application's URL
@BeforeClass
public void setUp() {
// Set up the WebDriver instance (you need to download and set up the WebDriver executable for your browser)
System.setProperty("webdriver.chrome.driver", "path_to_chromedriver_executable");
driver = new ChromeDriver();
driver.get(baseUrl);
}
@Test
public void testHomePage() {
// Perform actions and verifications for the home page
WebElement element = driver.findElement(By.id("element_id")); // Replace with the appropriate element locator
// Perform assertions to verify element state
assert element.isDisplayed();
}
@Test
public void testSomeOtherFunctionality() {
// Perform actions and verifications for another functionality
WebElement element = driver.findElement(By.cssSelector("css_selector")); // Replace with the appropriate element locator
// Perform assertions to verify element state
assert element.isEnabled();
}
// Add more test methods for different parts of your application
@AfterClass
public void tearDown() {
// Close the WebDriver instance and clean up resources
driver.quit();
}
}
In this example, the @Test methods define actual test cases. You'd want to customize them to cover whichever aspects of your application you want to evaluate.
3. Run Tests
With automated regression tests set up, the final step is simply to run the tests. You can start the tests manually; however, since you'll typically want to repeat regression tests every time significant changes appear within the application, it usually makes sense to integrate testing into your continuous delivery pipeline so that the tests are triggered automatically within the software development process.
Challenges You Might Face
While automated regression testing is a valuable means of protecting application quality without slowing down software delivery operations, it can pose some challenges.
Use Cases
The biggest, for many teams, is deciding exactly what and when to test using regression tests. As we mentioned, it's often not practical to test every aspect of an application following every change. QA engineers must make strategic, context-based decisions about when and how to test.
Time
A second challenge is that, even when they're automated, regression tests can take time. That's especially true if you need to run a large set of regression tests across multiple platforms. For this reason, QA engineers sometimes need to restrict which regression tests they run.
Delivery Operations
Keeping regression tests in sync with software delivery operations can also be challenging in some cases. To ensure that regression testing happens at the right point in the software delivery cycle, QA teams should collaborate with developers so they know when application updates will occur and when regression testing should follow. Communication with developers also helps ensure that regression tests don't cause unexpected delays in the software delivery pipeline, which could frustrate developers if it means that features they promised aren't delivered on time.
5 Regression Testing Best Practices
To perform regression testing as effectively and efficiently as possible, consider the following best practices:
Keep tests small: It's better to run a large set of small tests than to run a handful of tests that attempt to test many things at once. In other words, keep your regression tests focused and modular.
Be strategic about when to run tests: Not every single code change necessitates a regression test – and if you attempt to run tests whenever developers touch code in any way, you may end up with more tests than your pipeline can handle. Instead, define a minimum scope of changes that have to happen before regression tests occur.
Cover multiple changes with a single set of regression tests: You can also add efficiency to automated regression testing by waiting until developers have made several app updates before running your tests (assuming the updates appear in close proximity to each other). This is more efficient than running the same set of regression tests after each application update.
Integrate regression tests into CI/CD pipelines: As noted above, the repetitive nature of regression testing means that you should trigger regression tests automatically within your CI/CD pipeline, rather than expecting QA engineers to start the tests manually every time an application change occurs.
Consider multi-tiered regression tests: In some cases, it makes sense to run different "tiers" of regression tests following different application updates. For example, you might only run high-priority tests following small updates, but a major update would trigger a full suite of regression tests. This approach helps to save time and ensure that minor changes don't trigger a large set of regression tests that delay the software delivery pipeline.
Automate Your Regression Tests With Sauce Labs
If you want to ensure that software updates make applications better, not worse, and you also want to avoid delays to your software delivery pipeline, you need automated regression testing. Automating regression tests is the most efficient and lowest-risk approach to validating that software changes don't introduce unexpected problems. Learn more about how to improve your visual testing with automated visual regression testing.
And with the help of test automation tools and a test platform like Sauce Labs – which provides easy access to hundreds of devices and browsers for testing while also integrating with CI/CD pipelines to ensure efficient automated tests – running regression tests wherever and whenever you need is fast and easy.
