Istanbul plugin for Webpack

Istanbul code coverage loader for Webpack

Karma example

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

Unlike other examples, there is no webpack.config.js file. Instead, the karma.conf.js file file includes the webpack configuration. For more information about the karma.conf.js file, see the Karma documentation and the karma-coverage-istanbul-reporter documentation.


Folder/File Description
karma.conf.js The Karma config file. It includes the webpack configuration, including coverage-istanbul-loader. It also specifies where the test files are (**/*.spec.js), which browser(s) to test in (Chrome), etc.
src folder The original source code.
coverage/Chrome/ The code coverage data that’s produced by karma-coverage-istanbul-reporter. In this case, we’ve configured it to produce coverage data in lcov format, which is widely supported by services like Coveralls or Codacy.

Console Output

In addition to the file, test results and code coverage stats are also printed to the console when running the tests. The output looks like this:

Suites and tests results:

 - sayHello :
   * should say "hello, world" by default : ok
   * should say hello to a specific person, if specified : ok

Browser results:

 - Chrome 71.0.3578 (Windows 10.0.0): 2 tests
   - 2 ok


=============================== Coverage summary ===============================
Statements   : 100% ( 2/2 )
Branches     : 100% ( 1/1 )
Functions    : 100% ( 2/2 )
Lines        : 100% ( 2/2 )