anchor.diff:      tick(Duration.zero);
       tick(const Duration(seconds: 2));
       expect(statuses, <AnimationStatus>[AnimationStatus.forward]);
  +    controller.dispose();
     });
   
     test('Simulations run forward even after a reverse run', () {
  
positive.code:       tick(Duration.zero);
        tick(const Duration(milliseconds: 125));
        expect(controller.value, 1.0);
      },
    );
  
  
negative.code:     expect(controller.value, 0.0);
      expect(controller.status, AnimationStatus.dismissed);
      expect(statusLog, equals(<AnimationStatus>[ AnimationStatus.forward, AnimationStatus.completed, AnimationStatus.dismissed ]));
      controller.dispose();
    });
  
    test('setting value directly sets correct status', () {
  