commit 257d7c99293530caf1a1946dc1c649ce5b6f2966
from: Omar Polo <op@omarpolo.com>
date: Tue Oct 04 16:56:35 2022 UTC

fix last sender name/date in the index

pick up the *latest* From/Date for the indexes, not what happened to be
the last mail rendered in that thread.

spotted by stsp@

commit - debcbab21044d4ed53603bc14f0532ba6b3ba0b5
commit + 257d7c99293530caf1a1946dc1c649ce5b6f2966
blob - 5a543bbae24d8d5c7b11e208fe99d887809b228e
blob + c059ce5eb02d2aef78682f236e2fe94e06e4be1b
--- mkindex
+++ mkindex
@@ -210,10 +210,17 @@ while (<>) {
 	index_entry $pfh, $last_tid, $last_date, $last_from, $last_subj
 	    if defined $last_tid && $level == 0;
 
-	$last_tid = $mid if $level == 0;
-	$last_date = $date;
-	$last_from = $from;
-	$last_subj = $subj if $level == 0;
+	# `gt' on dates works because the format used allow for
+	# lexicographic comparisons.
+	if ($level == 0 || $date gt $last_date) {
+		$last_date = $date;
+		$last_from = $from;
+	}
+
+	if ($level == 0) {
+		$last_tid = $mid;
+		$last_subj = $subj;
+	}
 }
 
 index_entry $pfh, $last_tid, $last_date, $last_from, $last_subj