karma.conf.js

const path = require('path');

module.exports = function(config) {
    const testWebpackConfig = require('./webpack.test.js');
    const options = {

        // base path that will be used to resolve all patterns (e.g. files, exclude)
        basePath: '',

        /*
         * Frameworks to use
         *
         * available frameworks: https://npmjs.org/browse/keyword/karma-adapter
         */
        frameworks: ['jasmine'],

        // list of files to exclude
        exclude: [ ],

        /*
         * list of files / patterns to load in the browser
         *
         * we are building the test environment in ./spec-bundle.js
         */
        files: [ {
            pattern: './spec-bundle.js',
            watched: false
        } ],

        /*
         * preprocess matching files before serving them to the browser
         * available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
         */
        preprocessors: { './spec-bundle.js': ['webpack', 'sourcemap'] },

        // Webpack Config at ./webpack.test.js
        webpack: testWebpackConfig,

        coverageIstanbulReporter: {
            reports: ['html', 'text', 'lcov', 'text-summary'],
            dir: path.join(__dirname, 'coverage'),
            fixWebpackSourcePaths: true
        },

        // Webpack please don't spam the console when running in karma!
        webpackServer: { noInfo: true },

        /*
         * test results reporter to use
         *
         * possible values: 'dots', 'progress'
         * available reporters: https://npmjs.org/browse/keyword/karma-reporter
         */
        reporters: ['progress', 'coverage-istanbul'],

        // web server port
        port: 9876,

        // enable / disable colors in the output (reporters and logs)
        colors: true,

        /*
         * level of logging
         * possible values: config.LOG_DISABLE || config.LOG_ERROR || config.LOG_WARN || config.LOG_INFO || config.LOG_DEBUG
         */
        logLevel: config.LOG_INFO,

        // enable / disable watching file and executing tests whenever any file changes
        autoWatch: true,

        /*
         * start these browsers
         * available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
         */
        browsers: [
            'Chrome'
        ],

        customLaunchers: {
            Chrome_travis_ci: {
                base: 'Chrome',
                flags: ['--no-sandbox']
            }
        },

        /*
         * Continuous Integration mode
         * if true, Karma captures browsers, runs the tests and exits
         */
        singleRun: true,
        browserNoActivityTimeout: 50000
    };

    if (process.env.TRAVIS) {
        options.browsers = ['Chrome_travis_ci'];
    }

    config.set(options);

};