karma.conf.js

var path = require('path');

var singleStart = process.env.SINGLE_START;

// configures browsers to run test against
// any of [ 'ChromeHeadless', 'Chrome', 'Firefox ]
var browsers = (process.env.TEST_BROWSERS || 'ChromeHeadless').split(',');

// use puppeteer provided Chrome for testing
process.env.CHROME_BIN = require('puppeteer').executablePath();

var basePath = '.';

var absoluteBasePath = path.resolve(path.join(__dirname, basePath));

var suite = 'test/testBundle.js';


module.exports = function(karma) {

  var config = {

    basePath,

    frameworks: [
      'mocha',
      'sinon-chai'
    ],

    files: [
      suite
    ],

    preprocessors: {
      [ suite ]: [ 'webpack', 'env' ]
    },

    reporters: [ 'progress' ],

    browsers,

    browserNoActivityTimeout: 30000,

    singleRun: true,
    autoWatch: false,

    webpack: {
      mode: 'development',
      module: {
        rules: [
          {
            test: /\.css|\.xml$/,
            use: 'raw-loader'
          },
          {
            test: /\.(woff(2)?|ttf|eot|svg)(\?v=\d+\.\d+\.\d+)?$/,
            use: [ 'file-loader' ],
          }
        ]
      },
      resolve: {
        mainFields: [
          'dev:module',
          'browser',
          'module',
          'main'
        ],
        modules: [
          'node_modules',
          absoluteBasePath
        ]
      },
      devtool: 'eval-source-map'
    }
  };

  if (singleStart) {
    config.browsers = [].concat(config.browsers, 'Debug');
    config.envPreprocessor = [].concat(config.envPreprocessor || [], 'SINGLE_START');
  }

  karma.set(config);
};