A change might not have any categories.

It's possible that a client changed categories, thus adding the entry to the map table, but then also performed a separate change to that same message before the next sync request, which would not contain a categories entry.
horde · Feb 21, 2018 · 056419b · 056419b
1 parent 62a86fd
commit 056419b
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/lib/Horde/ActiveSync/State/Sql.php b/lib/Horde/ActiveSync/State/Sql.php
@@ -1357,7 +1357,7 @@ protected function _getMailMapChanges(array $changes)
                         $results[$row['message_uid']][$change['type']] =
                             (!is_null($row['sync_read']) && $row['sync_read'] == $change['flags']['read']) ||
                             (!is_null($row['sync_flagged']) && $row['sync_flagged'] == $change['flags']['flagged']) ||
-                            (!is_null($row['sync_category']) && $row['sync_category'] == md5(implode('', $change['categories'])));
+                            (!is_null($row['sync_category']) && !empty($change['categories']) && $row['sync_category'] == md5(implode('', $change['categories'])));
                         continue 3;
                     case Horde_ActiveSync::CHANGE_TYPE_DELETE:
                         $results[$row['message_uid']][$change['type']] =