05 — Glossary · Application & Data
Mutation Testing
GL-910 · also Mutation Analysis
A way to judge a test suite by making many small deliberate changes to the code, such as flipping a condition or altering a constant, and checking whether the tests fail. Each change the tests miss points to behavior that is not really being tested.
Coverage shows which lines ran; mutation testing shows whether the tests would notice those lines being wrong. Useful for judging tests written by coding agents, which can reach high coverage while checking little.
See also
In the catalog
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What is mutation testing? (Stryker Mutator) ↗
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