[Dovecot] [BUG] Lucene plugin breaks header substring search

[Timo Sirainen]

On 16.10.2012, at 6.45, Dave Abrahams wrote:

>>> According to the IMAP spec if I do a search for "TO isocpp.org" it
>>> should find all the messages whose To: field contains the string
>>> "isocpp.org", but dovecot is returning me an empty list.  However, a
>>> search for "TO tm at isocpp.org" produces a long list of messages.
>> 
>> This specific problem can be solved by:
>> 
>> plugin {
>>  fts_lucene = whitespace_chars=@.
>> }
> 
> OK, Google tells me that's documented at
> http://wiki2.dovecot.org/Plugins/FTS/Lucene but I only found it now
> because I knew what to look for.  I suggest doing something to make that
> more discoverable.

That is the only page where there is any information about fts-lucene. I made it a bit clearer in that page now that whitespace_chars should be used as default.

> This might be good enough for me, but still doesn't make it conforming
> to the IMAP spec, right?  IIUC the spec says you can search for
> arbitrary strings without regard to word boundaries.

It doesn't conform to the IMAP spec, correct. But nobody cares about that anymore. Everyone violates it.