Test Coverage Techniques Used In Software Testing

Can you test 100% of your application? Or can you cover every possible testing scenario? And how much time and resources should you allocate to make the software bug-free? There are multiple questions, and all their answers lie in Test coverage techniques.

In this blog, we will discuss the basics of test coverage

What is Test Coverage?

Test coverage is a percentage value that measures the tests that are executed from all the tests. This could be with respect to a feature too. This is a qualitative measurement and is a black box technique.

The formula for test coverage is:

Test Coverage = (number of tests executed/total number of tests)*100 If we have to say, with respect to a feature, Test Coverage for a feature = (number of tests executed for that feature/total number of tests for that feature)*100

Let’s take an example. If your code consists of 20,000 lines, and the test covers 15,000 lines of code, then the test coverage would be 75%.

But then, how does test coverage differ from code coverage? The latter refers to the percentage of code lines tested using at least one test case. It is a quantitative approach. As opposed to this, test coverage is a qualitative approach, which measures the efficiency and correctness of the tested code. You can read more about code and test coverage here.

Benefits of Test Coverage

Test coverage techniques drive testers to create tests that ensure maximum quality and minimum bugs. But before you start learning about these techniques, we would like to highlight the advantages of test coverage. They will help you understand why you should consider test coverage techniques for your testing methods.

• Test coverage identifies possible gaps in user requirements and test cases, focusing on product acceptance and better customer ratings.
• The better the test coverage, the less time and resources you require to move the application back and forth between the developers and these testers.
• When you focus on improving your test coverage, you optimize Regression testing, Unit testing, test case prioritization, test suit planning, and much more.
• It validates the application quality by covering every possible known test scenario and creating test cases to test the uncovered areas of the application.
• With test coverage, you can track and measure the quality of the software early in the development cycle, thereby increasing the ROI on automation testing.

Why Are Test Coverage Techniques Important for Test Automation?

Automated testing makes use of tools and test scripts to validate the application. The only manual intervention in automated testing is when testers write and run the scripts. Translating the manual cases to automation covers many scenarios to test the application in lesser time.

Thus, better test coverage can be achieved sooner. With test automation, you can also focus on areas that are easily missed or difficult to test manually. For instance, checking UI changes manually might seem easy, but pixel-by-pixel comparison and the right font and size can be accurately validated using visual test automation. You can use test coverage techniques and automation to analyze the priority of the test case and run them to get results.

One example of this could be an application that consists of multiple research papers, but only users with valid credentials can access them. In that case, identifying the correct logins and sessions per user is a critical task that is difficult to check with manual testing. Combining test coverage techniques with automation will clearly determine the areas that need attention and also provide quick testing of the complete scenario.

For automated testing, choose tools that support the implementation of test coverage techniques we are about to discuss in this blog. Testsigma is an AI-based test automation tool that automates your test cases using these techniques, which we will discuss in later sections.

Test Coverage Techniques You Should Know

Test coverage techniques help you to improve the quality of your tests and cover the code lines that are still invalid. There are primarily six techniques that are popular in the market:

Product Coverage

A product, here, is a software application that is built to solve some problem for a certain group of users. Product coverage measures the parts/sections of the product that have undergone testing against the total number of parts/sections of the product. It is the ratio between the tested parts to the total number of parts available for testing. Some ways of extending the technique range include making a checklist, prioritizing the product features, and automating the tests.

Risk Coverage

Another important criterion of the test coverage technique is risk coverage. It identifies all the risks associated with the software under development and tests them thoroughly to uncover bugs. The ideal way to proceed with risk coverage is to segment the tests into different categories:

• a likely scenario with a major impact
• an unlikely scenario with low impact
• an unlikely scenario with a major impact
• a likely scenario with low impact

Once you know what test cases come under which division, you can assign them priorities and continue the testing process.

Suppose you are to test an app that manages finances and personal data. In that case, identifying external and internal risks and testing all of those scenarios properly comes under risk coverage. Checking if there is any loophole in the payments page is a likely scenario with a major impact, and verifying that you can make two payments at once is an unlikely scenario with a major impact.

Requirements Coverage

As the name suggests, requirements coverage will measure how many requirements are tested.

Boundary Value Coverage

Boundary value testing is a type of testing that tests the boundary values for the input values being accepted by the application. With Boundary Value Coverage, you calculate the percentage of boundary value tests executed. This technique ensures that boundary-based testing is done for all the fields across the application.

Compatibility Coverage

Compatibility tests check the compatibility of an application with different platforms, browsers, and operating systems. Compatibility coverage will be the percentage of compatibility tests executed. Cross-browser testing is also a type of compatibility testing and is counted under compatibility coverage.

AI-Aided Test Automation

The testing tools that run on AI enable self-improving and self-maintaining test suites. With this, you can rely on robust test cases to provide your application with better test coverage that keeps improving. Testsigma is the new-age, AI-aided test automation tool that provides:

• Codeless testing – you only need to know simple English to automate tests
• Self-healing test cases, so their maintenance isn’t a huge task
• Reporting and analytics of the results for better collaboration across teams
• Offers compatibility to multiple third-party tools, including CI/CD integration, collaboration tools, and bug tracking
• Supports Agile and DevOps approach
• Executes web, application, mobile, and API testing on one unified platform
• You can start creating and executing your tests in minutes

Key Takeaway

Testing is important, but how much testing is important? What parameters exist to help you understand if you are testing the application enough? It’s test coverage. It measures the lines of code that have been tested against the total lines of code. The idea is to ensure that you know how much testing is over and how much is still left. And for that, you follow several test coverage techniques that we have mentioned in this blog.

From risk coverage and product coverage to automation and boundary-level evaluation, all these techniques will help you assess your testing efforts. And for everything automation, you already have Testsigma to assist you in no-code testing with all the benefits of test coverage. Explore our website for more information, and sign up for the free demo.

Try Testsigma to improve your testing coverage at 5x speed

Frequently Asked Questions (FAQs)

How do you measure test coverage?

Test coverage is a percentage value that calculates the line of code tested against the total lines of code available to test.

What are some of the test coverage best practices?

Test coverage best practices include

• Assessing the risk areas – Any area that is prone to failing and is user critical should be tested well.
• Reaching for almost 80% test coverage measurement – Write test cases that cover at least 80% of application features.
• Give priority to user requirements – Consider the functional and user requirements to implement the requirement coverage technique.
• Be smart during test case creation – use test coverage techniques that validate the right scenarios and cover the maximum amount of code.
• employing the right automation tools for testing – go for test automation tools that allow you to be flexible with your test automation approach and let you apply the test coverage techniques we discussed.