karma.conf.js

// Karma configuration

process.env.CHROME_BIN = require('puppeteer').executablePath();

module.exports = function(config) {

  config.set({

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

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

    jspm: {
      // Edit this to your needs
      loadFiles: ['test/setup.js', 'test/unit/**/*.js'],
      serveFiles: ['src/**/*.js', 'src/**/*.html', 'src/**/*.css'],
      paths: {
        '*': '*',
        'github:*': 'jspm_packages/github/*',
        'npm:*': 'jspm_packages/npm/*'
      }
    },

    // list of files / patterns to load in the browser
    files: [],

    // 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: {
      'test/**/*.js': ['babel'],
      'src/**/*.js': ['babel']
    },
    'babelPreprocessor': {
      options: {
        sourceMap: 'inline',
        presets: [ 'env', 'stage-0'],
        plugins: [
          'syntax-flow',
          'transform-decorators-legacy',
          'transform-flow-strip-types'
        ]
      }
    },

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

    // 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: ['ChromeHeadless'],

    // Continuous Integration mode
    // if true, Karma captures browsers, runs the tests and exits
    singleRun: false
  });
};