mbsync 1.3.1 deletes all local emails when syncing

[<gu...@ne...>]

Hello,


The latest version of mbsync (1.3.1, running on archlinux) sees the correct number of old messages on the server but when syncing it removes all messages in the local maildir.

Not the remote one, thankfully.

This only happens when synchronising this mailbox. Every mailbox has a very similar 

Downgrading to 1.3.0 fixes the issue.



Is anyone else seeing this?



Relevant config:



```

IMAPAccount NetC

Host mail.netcourrier.com

User gu...@ne...

PassCmd <redacted>

SSLType IMAPS



IMAPStore RemoteNetC

Account NetC



MaildirStore LocalNetC

Path ~/.maildirs/NetC/

Inbox ~/.maildirs/NetC/INBOX

SubFolders Verbatim



Channel NetC

Master :RemoteNetC:

Slave :LocalNetC:

CopyArrivalDate yes

Create Both

Remove Both

Expunge Both

Patterns * INBOX

Sync All

SyncState *

```



Sample output for `mbsync -VDCDmMNs NetC`:

```

S: Called get_box_path, ret=~/maildirs/NetC/INBOX

reading sync state ~/maildirs/NetC/INBOX/.mbsyncstate ...

Opening master box INBOX...

M: [ 5] Enter open_box

M: >>> 4 SELECT "INBOX"

M: [ 5] Leave open_box

Opening slave box INBOX...

S: [ 6] Enter open_box

S: [ 6] Callback enter open_box, sts=0, uidvalidity=1560541463

S: [ 6] Callback leave open_box

S: [ 6] Leave open_box

M: [ 4] Callback leave list_store

M: * 4445 EXISTS

M: * 0 RECENT

M: * OK [UNSEEN 4444]

M: * OK [UIDVALIDITY 1294943196]

M: * FLAGS (\Answered \Deleted \Draft \Flagged \Seen Sent)

M: * OK [PERMANENTFLAGS (\Answered \Deleted \Draft \Flagged \Seen Sent \*)]

M: 4 OK [READ-WRITE] SELECT

M: >>> 5 UID FETCH * (UID)

M: 5 OK UID FETCH done

M: [ 5] Callback enter open_box, sts=0, uidvalidity=1294943196

M: Enter prepare_load_box, opts=0xe7

M: Leave prepare_load_box, ret=0xe7

S: Enter prepare_load_box, opts=0xe7

S: Leave prepare_load_box, ret=0xe7

Loading master...

M: [ 7] Enter load_box, [1,inf] (new >= 0, seen <= 75750)

M: [ 7] Callback enter load_box, sts=0, total=4445, recent=0

master: 4445 messages, 0 recent

matching messages on master against sync records

M: [ 7] Callback leave load_box

M: [ 7] Leave load_box

Loading slave...

S: [ 8] Enter load_box, [1,inf] (new >= 0, seen <= 0)

S: [ 8] Callback enter load_box, sts=0, total=0, recent=0

slave: 0 messages, 0 recent

matching messages on slave against sync records

Synchronizing...

synchronizing old entries

synchronizing new entries

synchronizing flags

propagating new messages

M: Called get_uidnext, ret=1

S: Called get_uidnext, ret=0

expunging master

M: [ 9] Enter close_box

M: >>> 6 CLOSE

M: [ 9] Leave close_box

expunging slave

S: [ 10] Enter close_box

S: [ 10] Callback enter close_box, sts=0

S: [ 10] Callback leave close_box

S: [ 10] Leave close_box

S: [ 8] Callback leave load_box

S: [ 8] Leave load_box

M: [ 5] Callback leave open_box

M: 6 OK CLOSE done

M: [ 9] Callback enter close_box, sts=0

purging obsolete entries

max expired uid on master is now 0

```