Major Description
Found in SOLR-9180 testing.
when using RTG in a single node solr install, the [docid] transformer works for committed docs, but is silently missing from uncommited docs.
this inconsistency is confusing. It seems like even if there is no valid docid to return in this case, the key should still be present in the resulting doc.
I would suggest using either null or -1 in this case?
