Major Description
I'm working on improving Lucene's nightly benchmarks testing of faceting when I hit this:
FacetsConfig tries to detect if you are indexing the same field name more than once but you failed to tell it the field is multi-valued.
But the logic is too simplistic because if I index a field name with SortedSetDocValuesFacetField and also as a taxonomy based FacetField it currently rejects that but shouldn't.