[jira] [Created] (LUCENE-6400) SynonymParser should encode 'expand' correctly.

["Robert Muir (JIRA)" <ji...@apache.org>]

Robert Muir created LUCENE-6400:
-----------------------------------

             Summary: SynonymParser should encode 'expand' correctly.
                 Key: LUCENE-6400
                 URL: https://issues.apache.org/jira/browse/LUCENE-6400
             Project: Lucene - Core
          Issue Type: Bug
            Reporter: Robert Muir


Today SolrSynonymParser encodes something like A, B, C with 'expand=true' like this:
A -> A, B, C (includeOrig=false)
B -> B, A, C (includeOrig=false)
C -> C, A, B (includeOrig=false)

This gives kinda buggy output (synfilter sees it all as replacements, and makes all the terms with type synonym, positionLength isnt supported, etc) and it wastes space in the FST (includeOrig is just one bit). 

Example with "spiderman, spider man" and analysis on 'spider man'

Trunk:
term=spider,startOffset=0,endOffset=6,positionIncrement=1,positionLength=1,*type=SYNONYM*
term=spiderman,startOffset=0,endOffset=10,positionIncrement=0,*positionLength=1*,type=SYNONYM
term=man,startOffset=7,endOffset=10,positionIncrement=1,positionLength=1,*type=SYNONYM*

You can see this is confusing, all the words have type SYNONYM, because spider and man got deleted, and totally replaced by new terms (Which happen to have the same text).

Patch:
term=spider,startOffset=0,endOffset=6,positionIncrement=1,positionLength=1,*type=word*
term=spiderman,startOffset=0,endOffset=10,positionIncrement=0,*positionLength=2*,type=SYNONYM
term=man,startOffset=7,endOffset=10,positionIncrement=1,positionLength=1,*type=word*



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: dev-help@lucene.apache.org