Who is Testing the Tests?

on YouTube ↗07m

" summary

Mutation testing injects small faults (for example changing >= to <) and runs the suite to see which mutants survive, showing whether tests actually catch regressions. The demo runs StrykerJS, mutates 12 source files into 126 mutants, and reports a 85% mutation score while code coverage is 100%, revealing missing assertions and surviving operators. The tool generates per-file mutation reports so developers can add targeted tests until mutants are killed.

AI-written summary · about

" chapters (4)

1. 0:00Start
2. 0:32Code Coverage
3. 1:06Measure the Quality of Your Tests
4. 3:53What Kind of Mutations Can You Expect for Mutation Testing Frameworks

" related talks

• 29mWho is testing the test?Simon de Lang · JSWORLD Conference 2022 Online
• 22mKill All Mutants! (Introduction to Mutation Testing)Dave Aronson · JSConf Hawaiʻi 2020
• 41mMutation testing in practiceVadym Markelov · J-Fall Virtual 2020
• 21mKilling Mutants with Mutation TestingJosh Goldberg · DevReach 2023
• 26mMutation TestingArjan Dedgjonaj · Commit Your Code 2025
• 18mAttack of the mutants using mutation testing to improve your test suiteJeremy Nagel · Decompress AU 2018
• 50mMutation Testing in JavaScriptAndrey Kucherenko · JS Fest 2018
• 24mWho is testing your tests?Hugo van Rijswijk · Scala Love in the City 2021