code: func (actor Actor) GetCurrentDeployment(appGUID string) (string, Warnings, error) {
  	var collectedWarnings Warnings
  	deployments, warnings, err := actor.CloudControllerClient.GetDeployments(
  		ccv3.Query{Key: ccv3.AppGUIDFilter, Values: []string{appGUID}},
  		ccv3.Query{Key: ccv3.OrderBy, Values: []string{"-created_at"}},
  		ccv3.Query{Key: ccv3.PerPage, Values: []string{"1"}},
  	)
  	collectedWarnings = append(collectedWarnings, warnings...)
  	if err != nil {
  		return "", collectedWarnings, err
  	}
  
  	if len(deployments) < 1 {
  		return "", collectedWarnings, errors.New("failed to find a deployment for that app")
  	}
  
  	return deployments[0].GUID, collectedWarnings, nil
  }
docs: // TODO: add tests for get current deployment