Mutation Testing

on YouTube ↗26m

" summary

Mutation testing measures test quality by generating code variations and checking whether the test suite kills them For a NodeJS project this uses Stryker.js and can create 20–30k mutants for 6–10k lines of code The example shows 100% line coverage but only a 65.8% mutation score with 27 mutants killed and 14 surviving Reports show red dots on lines to fix CI integration, parallel runs, and per‑file thresholds make it practical and actionable

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" chapters (8)

1. 0:00Mutation testing intro
2. 1:05How mutation testing works
3. 3:34Problems mutation testing solves
4. 5:21Safe refactoring with mutation
5. 7:49Best practices for mutation
6. 10:17Thresholds and CI/CD
7. 12:04Live mutation testing demo
8. 18:29Real-world impact

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