// the current feature should be ignored, because it can use the external feature in the
// attributes and, therefore have a references to it. So, the delete functionality tries
// to delete this feature. Test case is creation of a constraint on external point,
// the current feature should be ignored, because it can use the external feature in the
// attributes and, therefore have a references to it. So, the delete functionality tries
// to delete this feature. Test case is creation of a constraint on external point,