Durable Test Collateral

Verification is part of the delivered project when it can prevent the same behavior from breaking again. Use the project's existing framework and conventions.

Keep the check with the project

For a bug fix or behavior change, add or update the smallest maintained test in the repository's normal test layout that exercises the changed behavior. If a specification makes a reusable suite or test category a deliverable, implement that suite instead of treating it as private verification.

An inline interpreter command, heredoc, scratch script, temporary-directory test, demo, or manual probe may help diagnose the problem, but it does not replace the maintained test. Keep a useful self-authored test unless the user explicitly asks for a disposable probe.