text: describe('Weighted Set', function () {
      beforeEach(angular.mock.module('freqModule'));
  
      it('should ', inject(['WeightedSet', function (WeightedSet) {
          var ws = new WeightedSet(
              ['牛奶', '啤酒', '尿布', '牛奶']
          );
  
          expect(ws.elements).toEqual({"牛奶":2,"啤酒":1,"尿布":1});
      }]));
  });