karma.config.js

/**
 * This is the Karma configuration file. It contains information about this skeleton
 * that provides the test runner with instructions on how to run the tests and
 * generate the code coverage report.
 *
 * For more info, see: http://karma-runner.github.io/0.12/config/configuration-file.html
 */
module.exports = function(config) {
  config.set({

    /**
     * These are the files required to run the tests.
     *
     * The `Function.prototype.bind` polyfill is required by PhantomJS
     * because it uses an older version of JavaScript.
     */
    files: [
      './test/polyfill.js',
      './test/main.js'
    ],

    /**
     * The actual tests are preprocessed by the karma-webpack plugin, so that
     * their source can be properly transpiled.
     */
    preprocessors: {
      './test/main.js': ['webpack']
    },

    /**
     * We want to run the tests using the PhantomJS headless browser.
     * This is especially useful for continuous integration.
     */
    browsers: ['PhantomJS'],

    /**
     * Use Mocha as the test framework, Sinon for mocking, and
     * Chai for assertions.
     */
    frameworks: ['mocha', 'sinon-chai'],

    /**
     * After running the tests, return the results and generate a
     * code coverage report.
     */
    reporters: ['progress', 'coverage'],

    /**
     * When generating a code coverage report, use `lcov` format and
     * place the result in coverage/lcov.info
     *
     * This file will be sent to Coveralls by the `coveralls` npm script.
     */
    coverageReporter: {
      dir: 'coverage/',
      reporters: [
        { type: 'lcovonly', subdir: '.', file: 'lcov.info' },
        { type: 'html', subdir: 'html' }
      ]
    },

    /**
     * The configuration for the karma-webpack plugin.
     *
     * This is very similar to the main webpack.local.config.js, with the
     * exception of specifying an istanbul-transformer post loader so
     * that we can generate an accurate code coverage report.
     */
    webpack: {
      module: {
        loaders: [
          { test: /\.jsx?$/, exclude: /node_modules/, loader: "babel-loader?stage=0"}
        ],
        postLoaders: [{
          test: /\.jsx?$/,
          exclude: /(test|node_modules)\//,
          loader: 'istanbul-instrumenter'
        }]
      },
      resolve: {
        extensions: ['', '.js', '.jsx']
      }
    },

    /**
     * Configuration option to turn off verbose logging of webpack compilation.
     */
    webpackMiddleware: {
      noInfo: true
    },

    /**
     * Once the mocha test suite returns, we want to exit from the test runner as well.
     */
    singleRun: true,

    /**
     * List of plugins
     */
    plugins: [
      'karma-mocha',
      'karma-webpack',
      'karma-coverage',
      'karma-sinon-chai',
      'karma-phantomjs-launcher'
    ],
  });
}