Istanbul code coverage loader for Webpack

This is a Webpack loader that uses Istanbul to add code coverage instrumentation to your code. This is especially useful for in-browser testing, in a tool like Karma, where you can use karma-coverage-istanbul-reporter to output code coverage data in a variety of formats that are supported by services like Coveralls or Codacy.

Coverage Istanbul Loader is based on Istanbul Instrumenter Loader, but uses a newer version of the Istanbul API and has better support for source maps.

Usage

See the examples folder for usage examples for various use cases.

• "hello, world" example
  This is the most simplistic example. It just uses coverage-istanbul-loader with its default options to produce an output bundle that contains code coverage instrumentation.

• TypeScript example
  This example demonstrates using coverage-istanbul-loader with transpiled code. It correctly maps the instrumented JavaScript code back to the original TypeScript source code.

• Karma example
  This example demonstrates using coverage-istanbul-loader with Karma and karma-coverage-istanbul-reporter to produce code coverage reports for browser tests.

• Example with options
  This example demonstrates passing options to coverage-istanbul-loader. The options are passed-on to istanbul-lib-instrument, so all the same options are supported.

Contributing

Contributions, enhancements, and bug-fixes are welcome! Open an issue on GitHub and submit a pull request.

Building/Testing

To build/test the project locally on your computer:

1. Clone this repo
   git clone https://github.com/JS-DevTools/coverage-istanbul-loader.git

2. Install dependencies
   npm install

3. Build the code
   npm run build

4. Run the tests
   npm test

License

coverage-istanbul-loader is 100% free and open-source, under the MIT license. Use it however you want.

This package is Treeware. If you use it in production, then we ask that you buy the world a tree to thank us for our work. By contributing to the Treeware forest you’ll be creating employment for local families and restoring wildlife habitats.

Big Thanks To

Thanks to these awesome companies for their support of Open Source developers ❤

Change Log

All notable changes will be documented in this file. coverage-istanbul-loader adheres to Semantic Versioning.

v3.0.0 (2020-03-05)

• Moved coverage-istanbul-loader to the @JSDevTools scope on NPM

• The "coverage-istanbul-loader" NPM package is now just a wrapper around the scoped "@jsdevtools/coverage-istanbul-loader" package

Full Changelog

v2.0.0 (2019-08-09)

• Major dependency updates that could have breaking changes

Full Changelog

v1.0.0 (2019-02-02)

Initial release 🎉