When should regression testing be conducted?

When should regression testing be conducted?

• A. After some code changes
• B. Before code is written
• C. During deployment
• D. Only in major releases

Answer: (A)

Regression testing is used to verify that recent code changes haven't broken existing functionality. Because this type of testing checks for unintended side effects after modifications, the right time to run it is after some code changes have been made. Running it before any code exists isn’t possible, and while testing often happens during deployment, regression testing specifically focuses on re-running the existing tests to ensure stability after changes, not just during production deployment. Limiting regression testing to major releases misses the fact that many defects can be introduced by smaller updates, so it’s important to run it whenever changes are made, not only in large releases.

Regression testing is used to verify that recent code changes haven't broken existing functionality. Because this type of testing checks for unintended side effects after modifications, the right time to run it is after some code changes have been made. Running it before any code exists isn’t possible, and while testing often happens during deployment, regression testing specifically focuses on re-running the existing tests to ensure stability after changes, not just during production deployment. Limiting regression testing to major releases misses the fact that many defects can be introduced by smaller updates, so it’s important to run it whenever changes are made, not only in large releases.