old_contents: 'use strict';
  
  var App = require('../../src/chrome/background');
  
  // a trivial example test
  describe('Sample test', function() {
  
    App.initialize();
  
    it('Should have a test variable set to 7', function() {
      expect(App.testVariable).toEqual(7);
    });
  
  });
  
new_contents: 'use strict';
  
  var App = require('../../src/chrome/background');
  
  // a trivial example test
  describe('Sample test', function() {
  
    beforeAll(function() {
      spyOn(window.chrome.runtime.onInstalled, 'addListener');
  
      App.initialize();
    });
  
    it('Should have a test variable set to 7', function() {
      expect(App.testVariable).toEqual(7);
    });
  
    it('should set up event listeners', function() {
      expect(window.chrome.runtime.onInstalled.addListener).toHaveBeenCalled();
    });
  });
  
subject: Add spy example test