Merge pull request 'export: write a message once, in every folder it was in' (#4) from fix/one-message-many-folders into main

2026-09-30 18:33:09 +00:00
parent 15b1cbd637 5ae0625ee1
commit 01ac1a5b3e
3 changed files with 571 additions and 43 deletions
@@ -197,6 +197,12 @@ created, and anything already on the target is left as it is -- an item that
 matches is not updated yet, so a change made at the source after the first
 export does not reach the target on a second one.

+Email is matched by Message-ID, or without one by sender, subject, date and
+recipients; where several messages share one, size decides. A message the
+source kept in several folders -- IMAP and Maildir copies, Gmail labels -- is
+written once, in all of them, and a later run adds any folder it is still
+missing on the target.
+
 `--prune` also deletes what is on the target and not in the archive. It asks
 first; `--yes` answers for it, for scripts. Export speaks JMAP only.