karma-coverage-istanbul-reporter

What is karma-coverage-istanbul-reporter?

The karma-coverage-istanbul-reporter is a Karma plugin that uses Istanbul to report code coverage. It provides detailed coverage reports in various formats and integrates seamlessly with Karma, a popular test runner for JavaScript.

What are karma-coverage-istanbul-reporter's main functionalities?

Basic Configuration

This feature allows you to configure the basic settings for the coverage reporter. You can specify the output directory, the types of reports to generate, and whether to fix Webpack source paths.

{"karma.conf.js":{"reporters":["progress","coverage-istanbul"],"coverageIstanbulReporter":{"dir":"coverage/","reports":["html","lcovonly","text-summary"],"fixWebpackSourcePaths":true}}}

Thresholds for Coverage

This feature allows you to set minimum coverage thresholds. If the coverage falls below these thresholds, the test run will fail.

{"karma.conf.js":{"coverageIstanbulReporter":{"thresholds":{"global":{"statements":80,"lines":80,"branches":80,"functions":80}}}}}

Custom Reporters

This feature allows you to generate custom reports in different formats such as HTML, lcov, text-summary, and JSON.

{"karma.conf.js":{"coverageIstanbulReporter":{"reports":["html","lcovonly","text-summary","json"]}}}

Other packages similar to karma-coverage-istanbul-reporter

karma-coverage

karma-coverage is another Karma plugin for code coverage reporting. It uses Istanbul for coverage and provides similar functionalities like generating reports in various formats. However, karma-coverage-istanbul-reporter is more modern and integrates better with Webpack.

karma-remap-istanbul

karma-remap-istanbul is a plugin that remaps coverage information to TypeScript source files. It is useful for projects using TypeScript, but for pure JavaScript projects, karma-coverage-istanbul-reporter is more straightforward.

README

karma-coverage-istanbul-reporter

A karma reporter that uses the latest istanbul 1.x APIs (with full sourcemap support) to report coverage.

About

This is a reporter only and does not perform the actual instrumentation of your code. Webpack users should use the istanbul-instrumenter-loader and then use this karma reporter to do the actual reporting. See the test config for an e2e example of how to combine them.

Installation

npm install karma-coverage-istanbul-reporter --save-dev

Configuration

// karma.conf.js
const path = require('path');

module.exports = function (config) {

  config.set({

    // ... rest of karma config

    // anything named karma-* is normally auto included so you probably dont need this
    plugins: ['karma-coverage-istanbul-reporter'],

    reporters: ['coverage-istanbul'],

    // any of these options are valid: https://github.com/istanbuljs/istanbul-api/blob/47b7803fbf7ca2fb4e4a15f3813a8884891ba272/lib/config.js#L33-L38
    coverageIstanbulReporter: {

       // reports can be any that are listed here: https://github.com/istanbuljs/istanbul-reports/tree/590e6b0089f67b723a1fdf57bc7ccc080ff189d7/lib
      reports: ['html', 'lcovonly', 'text-summary'],

       // base output directory. If you include %browser% in the path it will be replaced with the karma browser name
      dir: path.join(__dirname, 'coverage'),

       // if using webpack and pre-loaders, work around webpack breaking the source path
      fixWebpackSourcePaths: true,

      // stop istanbul outputting messages like `File [${filename}] ignored, nothing could be mapped`
      skipFilesWithNoCoverage: true,

       // Most reporters accept additional config options. You can pass these through the `report-config` option
      'report-config': {

        // all options available at: https://github.com/istanbuljs/istanbul-reports/blob/590e6b0089f67b723a1fdf57bc7ccc080ff189d7/lib/html/index.js#L135-L137
        html: {
          // outputs the report in ./coverage/html
          subdir: 'html'
        }

      },

       // enforce percentage thresholds
       // anything under these percentages will cause karma to fail with an exit code of 1 if not running in watch mode
      thresholds: {
        global: { // thresholds for all files
          statements: 100,
          lines: 100,
          branches: 100,
          functions: 100
        },
        each: { // thresholds per file
          statements: 100,
          lines: 100,
          branches: 100,
          functions: 100
        }
      }

    }

  });

}

List of reporters and options

• clover
• cobertura
• html
• json-summary
• json
• lcov
• lcovonly
• none
• teamcity
• text-lcov
• text-summary
• text

Credits

• Original karma-coverage source
• Example of using the new reporter API
• Karma remap istanbul

License

MIT