karma.conf.js

/**
 * @see https://karma-runner.github.io/6.4/config/configuration-file.html
 */
module.exports = (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: ['mocha', 'chai', 'commonjs'],

    // list of files / patterns to load in the browser
    files: [
      'dist/*.js',
      'lib/client/constants.js',
      'lib/server/utilities.js',
      'test/cases/html.js',
      'test/client/*.js',
      'test/helpers/*.js',
    ],

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

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

    // test results reporter to use
    // possible values: 'dots', 'progress'
    // available reporters: https://npmjs.org/browse/keyword/karma-reporter
    reporters: ['mocha', '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, currently available:
    // - Chrome
    // - ChromeCanary
    // - Firefox
    // - Opera (has to be installed with `npm install karma-opera-launcher`)
    // - Safari (only Mac; has to be installed with `npm install karma-safari-launcher`)
    // - PhantomJS
    // - IE (only Windows; has to be installed with `npm install karma-ie-launcher`)
    // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
    browsers: ['Chrome'],

    // If browser does not capture in given timeout [ms], kill it
    captureTimeout: 60000,

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

    // Concurrency level
    // how many browser should be started simultaneous
    concurrency: Infinity,

    // Client options
    client: {
      mocha: {
        // change Karma's `debug.html` to the Mocha web reporter
        reporter: 'html',
      },
    },

    // Mocha reporter options
    // https://www.npmjs.com/package/karma-mocha-reporter
    mochaReporter: {
      showDiff: true,
    },
  });
};