karma.conf.js

module.exports = function(config) {
  const webpackConfig = {
    node: {
      fs: 'empty',
      global: true,
      crypto: 'empty',
      tls: 'empty',
      net: 'empty',
      process: true,
      module: false,
      clearImmediate: false,
      setImmediate: false
    }
  };
  config.set({
    basePath: '.',

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

    // list of files / patterns to load in the browser
    files: [{ pattern: 'build/test.js', watched: false }],

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

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

    reporters: ['dots'],

    webpack: webpackConfig,

    webpackMiddleware: {
      stats: 'errors-only'
    },

    plugins: [
      require('karma-jasmine'),
      require('karma-chrome-launcher'),
      require('karma-webpack')
    ],

    // web server port
    port: 9876,

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

    // level of logging
    logLevel: config.LOG_INFO,

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

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

    browsers: process.env.TRAVIS ? ['Chrome_travis_ci'] : ['Chrome'],

    // Concurrency level
    // how many browser should be started simultaneous
    concurrency: Infinity
  });
};