From: Eric Wong <e@80x24.org>
Date: Fri, 19 Feb 2021 12:09:53 +0000 (-0700)
Subject: net_reader: handle single-message IMAP mailboxes
X-Git-Tag: v1.7.0~1102
X-Git-Url: http://www.git.stargrave.org/?a=commitdiff_plain;h=74e31aec6f66f695850bacf6379a034ea49a1d28;p=public-inbox.git

net_reader: handle single-message IMAP mailboxes

Due to an off-by-one error, we were unable to read mailboxes
with only a single message of UID:1.  Without this fix, the
message with UID:1 could only be read after UID:2 was created;
so there's no permanent data loss as long as a new message
showed up.

This affects all releases of public-inbox-watch with IMAP
support, though it probably went unnoticed because single
message inboxes are rare.
---

diff --git a/lib/PublicInbox/NetReader.pm b/lib/PublicInbox/NetReader.pm
index 61ea538b..22ba4be7 100644
--- a/lib/PublicInbox/NetReader.pm
+++ b/lib/PublicInbox/NetReader.pm
@@ -353,17 +353,18 @@ sub _imap_fetch_all ($$$) {
 			PublicInbox::IMAPTracker->new($url) : 0;
 	my ($l_uidval, $l_uid) = $itrk ? $itrk->get_last : ();
 	$l_uidval //= $r_uidval; # first time
-	$l_uid //= 1;
+	$l_uid //= 0;
 	if ($l_uidval != $r_uidval) {
 		return "E: $url UIDVALIDITY mismatch\n".
 			"E: local=$l_uidval != remote=$r_uidval";
 	}
 	my $r_uid = $r_uidnext - 1;
-	if ($l_uid != 1 && $l_uid > $r_uid) {
+	if ($l_uid > $r_uid) {
 		return "E: $url local UID exceeds remote ($l_uid > $r_uid)\n".
 			"E: $url strangely, UIDVALIDLITY matches ($l_uidval)\n";
 	}
 	return if $l_uid >= $r_uid; # nothing to do
+	$l_uid ||= 1;
 
 	warn "# $url fetching UID $l_uid:$r_uid\n" unless $self->{quiet};
 	$mic->Uid(1); # the default, we hope