PARTIALLY REMOVING MAXAGE (was: [PATCH v4] make maxage use UIDs to avoid timezone issues)

[Janna Martl]

On Tue, Mar 31, 2015 at 04:53:28AM -0400, Janna Martl wrote:
>remove IMAP-IMAP support for maxage; add startdate, folder_startdate to compensate
>
>maxage was fundamentally wrong in the IMAP-IMAP case: it assumed that
>remote messages have UIDs in the same order as their local counterparts,
>which could be false, e.g. when messages are copied in quick succession.
>So, remove support for maxage in the IMAP-IMAP case.
>
>Instead, support a special case of date restriction in IMAP-IMAP syncs:
>suppose there's a pre-existing IMAP folder that you want to sync to a
>new, empty folder, but you only want to sync the messages after a
>certain date. This date can be specified by the configuration option
>folder_startdate. On all subsequent syncs, the messages in the original
>folder after folder_startdate, and all the messages in the new folder,
>are considered.
>
>Also add the option startdate, which is similar to maxage but involves
>syncing messages after a fixed date, instead of a fixed number of days
>ago. This is not supported in the IMAP-IMAP case for the same reasons as
>maxage.

More notes about this:

* I took out the bit in folder/IMAP.py _msgs_to_fetch(), where we expand
the list to min(uids within maxage). The reason was that it would only
be used on an initial sync (where the Maildir was empty), and the extra
messages would get filled in on the next sync. I don't have a strong
opinion about this.

* The startdate option doesn't have anything to do with what we were
talking about; it was something that I'd kind of wanted, and seemed easy
once I'd done the rest of this.

* I think I should test this more, but am sending it so you can comment.

Sorry for holding up the show with this,

-- J.M.