https://tomasalmeida.pro/tags/mutation-testing/ Recent content in Mutation-Testing on Tomás Dias Almeida notes Hugo en-us Tue, 10 Nov 2026 20:14:46 +0100 https://tomasalmeida.pro/posts/2026/11/mutation-testing-ai-generated-code/ Tue, 10 Nov 2026 12:00:00 +0100 https://tomasalmeida.pro/posts/2026/11/mutation-testing-ai-generated-code/ <p>AI coding assistants can generate a working implementation in a few seconds. They can also generate a test suite that passes in the same amount of time. That speed is useful, but a green test run does not tell us whether the tests would catch a real defect.</p> <p>Mutation testing gives us a practical way to check that question. A mutation tool makes small changes to the production code, runs the test suite, and reports which changes the tests detected. The changed programs are called mutants. A test suite that fails when a mutant is present has killed that mutant. A surviving mutant shows a behavior that the tests did not distinguish.</p>