What are some common mistakes to avoid in white-box testing?

1 Choosing the wrong level of coverage

One of the main challenges of white-box testing is deciding how much of the code to test and what criteria to use. There are different levels of coverage, such as statement coverage, branch coverage, path coverage, and condition coverage, that measure how thoroughly the code is tested. However, higher levels of coverage do not necessarily mean better testing. They can also increase the complexity, cost, and time of testing. Therefore, it is important to choose the appropriate level of coverage based on the objectives, scope, and resources of the testing project. A good practice is to use a combination of coverage levels and prioritize the most critical and risky parts of the code.

2 Ignoring the user perspective

Another common mistake in white-box testing is focusing too much on the code and ignoring the user perspective. While white-box testing can reveal the technical aspects of the system, it cannot guarantee that the system meets the user requirements and expectations. Therefore, it is essential to complement white-box testing with black-box testing, which tests the system from the user point of view. Black-box testing can help validate the functionality, usability, and reliability of the system. It can also help identify any gaps or inconsistencies between the code and the user needs.

3 Overlooking the test design

A third common mistake in white-box testing is overlooking the test design. Test design is the process of creating test cases, test data, and test procedures that can effectively test the code. However, some testers may neglect the test design and rely on ad hoc or random testing. This can lead to poor test quality, low test coverage, and missed defects. Therefore, it is important to follow a systematic and rigorous test design process that can ensure the completeness, correctness, and consistency of the test cases. A good practice is to use test design techniques, such as boundary value analysis, equivalence partitioning, and decision tables, that can help generate test cases based on the code logic and structure.

4 Forgetting the maintenance

A fourth common mistake in white-box testing is forgetting the maintenance. Maintenance is the process of updating, modifying, and improving the test cases and test data as the code changes. However, some testers may forget the maintenance and use outdated or irrelevant test cases and test data. This can lead to false positives, false negatives, and inaccurate test results. Therefore, it is important to keep track of the code changes and update the test cases and test data accordingly. A good practice is to use version control tools, such as Git or SVN, that can help manage and document the code and test changes.

5 Neglecting the documentation

A fifth common mistake in white-box testing is neglecting the documentation. Documentation is the process of recording and reporting the test activities, results, and issues. However, some testers may neglect the documentation and skip or delay the test reporting. This can lead to poor communication, collaboration, and transparency among the testing team and other stakeholders. Therefore, it is important to document the test process and outcomes in a clear, concise, and consistent manner. A good practice is to use test documentation standards, such as IEEE 829 or ISO 29119, that can help define and structure the test documentation.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?