This is how code coverage testing helps improve software quality

Why is code coverage testing important for software quality?

With code coverage testing, you find weaknesses in the code of software. This is hugely important because it helps to improve software quality. The test ensures that all parts of the code are thoroughly tested. Thus, you find bugs and errors in the software on time and improve the quality of the software.

How code coverage testing works

There are three steps that well illustrate how this test design technique works:

1. Collecting coverage data

Collecting coverage data begins with running tests on the software. As you run the tests, you collect information about which lines of code are executed. As a developer, you can choose to do this manually, running the code and taking notes. But usually this process is automated using a code coverage tool.

The tool tracks code execution and keeps track of which lines are executed. This information is then stored in a file called coverage data. This file contains information about which lines of code were or were not executed.

2. Analyzing coverage data

Analyzing coverage data is the next step. This involves analyzing the data to determine which parts of the code have or have not been properly tested. You do this manually by looking at the file and analyzing which lines were executed, and which were not.

However, most code coverage tools also offer analysis capabilities, such as generating reports or visualizing code coverage. These reports provide information about the test coverage of the software and show which parts of the code have not been tested.

3. Assessing the quality of test coverage

Assessing the quality of test coverage is the final step. This involves determining how effective the tests have been in testing the software. Assessing the quality of test coverage involves looking at what parts of the code have not been tested.

If there are significant parts of the code that have not been tested, this may indicate weaknesses in the testing. This may be an indication that tests need to be modified to better test these areas. It is important to regularly perform code coverage testing and assess test coverage. This will help you improve the quality of the software and detect any errors in the code.

Read tip! Test varieties: what is it and why do you need them?

Types of code coverage

To make sure that you cover and examine all the different aspects of the code properly, it is important to perform different types of code coverage testing. This is because each type provides different information about test coverage. The different types of code coverage tests are:

Statement coverage

The most basic form is the statement coverage test. It measures the extent to which each line of code in a software program is executed while running tests. This method only measures whether each line of code has been executed at least once, not whether the code works correctly.

Branch coverage

Branch coverage is a method that checks the branches of code. It measures whether every possible execution path of a given decision structure (for example, an if statement or a switch statement) is tested. Branch coverage is thus more comprehensive than statement coverage because it measures all possible decisions tested within the code.

Path coverage

Path coverage is the most comprehensive and thorough form of code coverage testing. This type of test measures whether all possible execution paths through a piece of code have been tested. This includes all possible combinations of decisions and loop structures. Thus, this type of coverage is the most thorough, but it is also the most time-consuming and expensive to perform.

You can also read more about mutation testing or boundary value analysis!

Benefits of code coverage testing

Increased software quality

Code coverage testing helps increase software quality by identifying code weaknesses. This reduces the chances of bugs and errors in the software, thus increasing software quality.

Increased developer productivity

Testing can also help increase developer productivity. By running targeted tests on the parts of the code with low coverage, developers can test more efficiently and reduce the overall time required for software testing.

Improved maintainability of code

It also provides improved maintainability of the code. This is because testing allows you to know which parts of the code have not been properly tested, so you can run targeted tests to improve these parts of the code.

Code coverage testing for higher software quality

Code coverage testing is an important method for testing software and improving software quality. It can help developers identify code weaknesses and ensure that all parts of the code are thoroughly tested. Want to learn more about this? In our e-learning TMap Quality for cross-functional teams, we cover this test, and more, in depth.

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