code: function extendConfig (config, argv) {
    const cliArgs = {}
    let key
  
    for (key in defaultOptions.get()) {
      cliArgs[key] = argv[key]
    }
    if (argv.port) {
      overrideEndpointOption('port', argv.port, 'websocket', config)
    }
    if (argv.host) {
      overrideEndpointOption('host', argv.host, 'websocket', config)
    }
    if (argv.httpPort) {
      overrideEndpointOption('port', argv.httpPort, 'http', config)
    }
    if (argv.httpHost) {
      overrideEndpointOption('host', argv.httpHost, 'http', config)
    }
  
    return utils.merge({ plugins: {} }, defaultOptions.get(), config, cliArgs)
  }
docs: Augments the basic configuration with command line parameters
  and normalizes paths within it
  
  @param   {Object} config    configuration
  @param   {Object} argv      command line arguments
  @param   {String} configDir config directory
  
  @private
  @returns {Object} extended config