old_contents: define(function (require, exports, module) {
    'use strict';
  
    var AppInit = app.getModule('utils/AppInit');
    var Core = app.getModule('core/Core');
    var PreferenceManager = app.getModule('core/PreferenceManager');
  
    var preferenceId = 'ruby';
  
    var rubyPreferences = {
    };
  
    function getId() {
      return preferenceId;
    }
  
    AppInit.htmlReady(function () {
      PreferenceManager.register(preferenceId, 'Ruby', rubyPreferences);
    });
  
    exports.getId = getId;
  });
  
new_contents: define(function (require, exports, module) {
    'use strict';
  
    var AppInit = app.getModule('utils/AppInit');
    var Core = app.getModule('core/Core');
    var PreferenceManager = app.getModule('core/PreferenceManager');
  
    var preferenceId = 'ruby';
  
    var rubyPreferences = {
      'ruby.gen': {
        text: 'Ruby Code Generation',
        type: 'Section',
      },
      'ruby.gen.toStringMethod': {
        text: 'to_s method',
        description: 'Generate to_s method.',
        type: 'Check',
        default: true,
      }
    };
  
    function getId() {
      return preferenceId;
    }
  
    function getGenerateOptions() {
      return {
        rubyToStringMethod: PreferenceManager.get('ruby.gen.toStringMethod'),
      };
    }
  
    AppInit.htmlReady(function () {
      PreferenceManager.register(preferenceId, 'Ruby', rubyPreferences);
    });
  
    exports.getId = getId;
    exports.getGenerateOptions = getGenerateOptions;
  });
  
subject: Add generate to_s method option