istanbul-auto-ignore

Motivation

• When writing a tests driven projects, we find it best to set jest coverageThreshold option to 100, because each untested code will fail the build and be noticed.
• Sometimes a code can't be tested for various reasons, but setting coverageThreshold to less than 100 will make newly untested code harder to find.
• Therefore we find it best to use coverageThreshold set to 100, and add //istanbul ignore (coverage ignore) comments instead of setting coverageThreshold to anything less.
• istanbul-auto-ignore helps an existing project with coverageThreshold < 100 to get to 100 by adding //istanbul ignore comments next to uncovered code.

How to use

• Make sure your project have a coverage/coverage-final.json file. In order to generate one run jest with collectCoverage set to true and coverageReporters set to ["json"].
• run npx istanbul-ignore-legacy