karma.conf.js

// Karma configuration
const webpackConfig = require('./config/webpack.config.test');

webpackConfig.watch = true;

const filePattern = 'src/**/*.test.js';
const fileRoot = 'src/tests.js';
const onJenkins = process.env.ON_JENKINS;
process.env.BABEL_ENV = 'test';
module.exports = function (config) {
  config.set({
    // base path that will be used to resolve all patterns (eg. files, exclude)
    basePath: '',
    frameworks: ['mocha', 'chai'],
    files: [
      fileRoot,
      { pattern: filePattern, included: false, served: false, watched: false },
    ],
    preprocessors: {
      '**/*.js': ['sourcemap'],
      [fileRoot]: ['webpack'],
    },
    reporters: ['coverage', 'mocha'],
    coverageReporter: {
      reporters: [
        {
          type: 'json',
          dir: 'coverage/',
        },
        {
          type: onJenkins ? 'lcov' : 'html',
          dir: 'coverage/',
        },
      ].concat(onJenkins ? { type: 'text' } : []),
    },
    webpack: webpackConfig,
    webpackMiddleware: {
      noInfo: true,
      // and use stats to turn off verbose output
      stats: {
        // options i.e.
        chunks: false,
      },
    },
    port: 9876,
    colors: true,
    logLevel: config.LOG_INFO,
    autoWatch: false,
    browsers: ['ChromeHeadless'],
    singleRun: true,
    browserNoActivityTimeout: 60000,
    browserDisconnectTolerance: 3,
    concurrency: Infinity,
  });
};