This problem was posted by me and also brucek some time ago but seems to persist in 1.7rc1. Bruce had a go at trying to resolve it and I am sure if he was successful he would have posted the solution.
The following expression in a display template used to print the whole tree-
<case><if rule="^ca_objects.type_id =~ /Printed Documents/"> ^ca_objects.printed_document_objects.hierarchy.preferred_labels.name_plural%delimiter=_➞_
no longer displays the hierarchal list starting from the top down to
the bottom I now get the bottom item displayed repeatedly like this.
Book, Time ➞ Book, Time ➞ Book, Time ➞ Book, Time.
Using ubuntu 16.04.4 Firefox 52.02, PHP 7.0.15 Providence 1.7rc1 schema 146