text: describe("Ext.mixin.Identifiable", function () {
      var TestClass;
  
      beforeEach(function () {
          TestClass = new Ext.Class({
              mixins: [Ext.mixin.Identifiable]
          });
      });
  
      describe("getId()", function () {
          it("should return a unique id and cache it", function () {
              var foo = new TestClass(),
                  id1 = foo.getId(),
                  id2 = foo.getId();
  
              expect(id1).toBe(id2);
          });
  
          it("should return unique ids", function () {
              var foo = new TestClass(),
                  bar = new TestClass(),
                  id1 = foo.getId(),
                  id2 = bar.getId();
  
              expect(id1).not.toEqual(id2);
          });
      });
  });
  