Mutation Testing in JavaScript

on YouTube ↗50m

" summary

Mutation testing for JavaScript uses the Striker tool (npm install striker; striker run) to create mutants (binary, boolean, statement removal) and shows it finds weaknesses that coverage misses — a demo calculator with 100% line coverage still leaves ~50% of mutants alive. The talk explains TypeScript support, practical workflow, real limits on large codebases (~10k LOC) including performance and dynamic-import issues, and recommends running mutation tests periodically and tracking mutation score instead of running them on every commit.

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" chapters (7)

1. 0:00Introduction
2. 8:59What is mutation testing
3. 12:36Striker setup first run
4. 18:30Mutation types in Striker
5. 24:44Mutation testing limits
6. 35:49Q&A
7. 46:53Summary

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