99% is not enough - full test coverage and why it's awesome
summary
Argues for aiming for true 100% line, branch, statement and function coverage and shows how that changes design, not just test quantity. Mentions concrete tools and options like --100 flag (node-tap), nyc and Istanbul hooks, and a coverage map to keep base classes honestly tested. Gives surprising emotional data points — slipping from 100% to 99.5% feels awful — and practical hacks like the mutate FS module and istanbul ignore to handle genuinely untestable edges.
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chapters (8)
- 0:00Introduction
- 0:35The Purpose of Testing
- 2:12Understanding Coverage
- 3:24Strategic Advantages
- 4:29Achieving Full Coverage
- 5:44Addressing Objections
- 7:06Writing Better Tests
- 8:32Advanced Coverage Techniques
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