anchor.diff:          });
   
           test('should add event before advancing time', () {
  -          return new FakeAsync().run((async) {
  +          return new Future(() => new FakeAsync().run((async) {
               var controller = new StreamController();
               var ret = controller.stream.first.then((_) {
                 expect(async.getClock(initialTime).now(), initialTime);
  
positive.code:             expect(errors.first, new isInstanceOf<TimeoutException>());
              return controller.close();
            });
  
          });
  
        });
  
      });
  
    });
  
  }
  
negative.code:             controller.add(null);
              async.elapse(const Duration(minutes: 1));
              return ret;
            }));
          });
  
          test('should increase negative duration timers to zero duration', () {
  