code: function setupConfig(options) {
      if (options.resetConfig) {
          // Reset your environment variables for resetting node-config module. node-config is a singleton.
          // For testing it's necessary to reset and this is a workaround from node-config support.
          global.NODE_CONFIG = null;
          delete require.cache[require.resolve('config')];
          config = require('config');
          delete options.resetConfig;
      }
  
      var customConfigFile, customConfig,
          defaultConfig       = require('../config/default.js');
  
      options = options || {};
  
      if (options.config) {
          customConfigFile    = options.config.charAt(0) === '/' || options.config.charAt(0) === '\\' ? options.config : path.join(process.cwd(), options.config); // Absolute or relative
          customConfig        = require(customConfigFile);
      }
  
      delete options.config;
  
      // Combine configs and override lower priority configs.
      config.util.extendDeep(config, defaultConfig, customConfig || {}, { "sequelize-pg-generator": options });
  }
docs: Combines default configuration, custom config file and command line options by overriding lower priority ones.
  @private
  @param {object} options - Options converted to config structure.