Well-constructed test message.  Xapian's query parser is actually doing the
right thing [1] and this is a bug in the way notmuch indexes address list
headers.  For each address, _notmuch_message_gen_terms resets the term
generator's term position, so your To header indexes with positions as
  c:1 hello:2 com:3 K:1 R:2 world:3 com:4
Thus, the phrase query "hello world" matches hello in position 2 and world
in position 3.  Probably the right thing for notmuch to do is to jump up the
term generator position between each address so phrase queries don't cross
them or span them.

[1] Your to:\'$WORD1@$WORD2\' query didn't work because Xapian doesn't
accept a single quote after a prefix.

On Tue, Jan 25, 2011 at 6:29 PM, Mark Anderson <MarkR.Anderson@amd.com>wrote:

> Hi guys, What's up? ("Notmuch")
>
> Apparently matching on email addresses doesn't work the way I hoped.
>
> While debugging why my to:x@y.com <to%3Ax@y.com> search was matching far
> too many
> entries, I whittled it down to this:
>
> WORD1=hello
> WORD2=goodbye
> MSGID=junk$(date +%s)
> TESTDIR=$(notmuch config get database.path)/.tmp/new
> TESTMAIL=$TESTDIR/$MSGID:2,
>
> mkdir -p $TESTDIR
>
> echo Testcase for $WORD1@$WORD2, msgid: $MSGID@junk.com
>
> echo "From: nobody@nobody.com
> To: c@${WORD1}.com, K-R@${WORD2}.com
> Date: Mon, 24 Jan 2011 23:41:34 -0600
> Subject: Error
> Message-ID: <$MSGID@junk.com>
>
> Not empty body.=
>
> " > $TESTMAIL
>
> notmuch new
> notmuch search --output=files to:$WORD1@$WORD2
> notmuch search --output=files to:\"$WORD1@$WORD2\"
>
> Why does that match, but this doesn't?
>
> notmuch search --output=files to:\'$WORD1@$WORD2\'
>
> Apparently single quotes are the only quote for Xapian's parser?
>
> I guess this is a strong vote for the quick integration of the custom
> parser with optimization passes that turn emails into phrases that can't
> match across multiple emails.
>
> This was just an egregious example of notmuch giving me notmuch of what
> I wanted, or actually, far too much of what I didn't want.
>
> Thanks,
> -Mark
>
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