[honey] Don't allow mixed wdf for a term
commit68c1da95b835ca2abcc19f4cd2a6aafd6e23efd3
authorOlly Betts <olly@survex.com>
Wed, 4 Apr 2018 00:31:09 +0000 (4 12:31 +1200)
committerOlly Betts <olly@survex.com>
Wed, 4 Apr 2018 02:16:38 +0000 (4 14:16 +1200)
tree1825700ca2db4802d3d167a1beb91ba82d4ca478
parent963048332bf135457ca163dc339579d0a710a26e
[honey] Don't allow mixed wdf for a term

A given term in a honey database must either always have wdf=0 (i.e.
a boolean term) or never have wdf=0.

Currently we make use of this to reduce the size of the postlist header
and to avoid storing wdf explicitly when we can deduce it must be 1 for
the second and subsequent occurrence.
xapian-core/backends/honey/honey_compact.cc
xapian-core/backends/honey/honey_postlist.cc
xapian-core/backends/honey/honey_postlist_encodings.h
xapian-core/backends/honey/honey_table.h
xapian-core/backends/honey/honey_version.cc