code: func (r *ControllerExpectations) SetExpectations(controllerKey string, add, del int) error {
  	exp := &ControlleeExpectations{add: int64(add), del: int64(del), key: controllerKey, timestamp: clock.RealClock{}.Now()}
  	klog.V(4).Infof("Setting expectations %#v", exp)
  	return r.Add(exp)
  }
docs: // SetExpectations registers new expectations for the given controller. Forgets existing expectations.