search: allow searching within mail diffs

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1 files changed, 16 insertions, 4 deletions

diff --git a/lib/PublicInbox/Search.pm b/lib/PublicInbox/Search.pm
index 67837f4f..c7c5455d 100644
--- a/lib/PublicInbox/Search.pm
+++ b/lib/PublicInbox/Search.pm
@@ -75,6 +75,14 @@ my %prob_prefix = (
 
         q => 'XQUOT',
         nq => 'XNQ',
+        dfn => 'XDFN',
+        dfa => 'XDFA',
+        dfb => 'XDFB',
+        dfhh => 'XDFHH',
+        dfctx => 'XDFCTX',
+        dfpre => 'XDFPRE',
+        dfpost => 'XDFPOST',
+        dfblob => 'XDFPRE XDFPOST',
 
         # default:
         '' => 'XMID S A XNQ XQUOT XFN',
@@ -98,12 +106,16 @@ EOF
         'a:' => 'match within the To, Cc, and From headers',
         'tc:' => 'match within the To and Cc headers',
         'bs:' => 'match within the Subject and body',
+        'dfn:' => 'match filename from diff',
+        'dfa:' => 'match diff removed (-) lines',
+        'dfb:' => 'match diff added (+) lines',
+        'dfhh:' => 'match diff hunk header context (usually a function name)',
+        'dfctx:' => 'match diff context lines',
+        'dfpre:' => 'match pre-image git blob ID',
+        'dfpost:' => 'match post-image git blob ID',
+        'dfblob:' => 'match either pre or post-image git blob ID',
 );
 chomp @HELP;
-# TODO:
-# df (filenames from diff)
-# da (diff a/ removed lines)
-# db (diff b/ added lines)
 
 my $mail_query = Search::Xapian::Query->new('T' . 'mail');