var Gallery = { timeout: 3000, setTimeout: function (num) { this.timeout = num } }; var myGallery = _.extend({}, Gallery); myGallery.setTimeout(5000); var otherGallery = _.extend({}, Gallery); otherGallery.setTimeout(1000); describe("myGallery", function() { it('should have a timeout of 5000', function() { expect(myGallery.timeout).toEqual(5000); }); }); describe('otherGallery', function() { it('should have a timeout of 1000', function() { expect(otherGallery.timeout).toEqual(1000); }); });