"Bouncing" between branch imports and branch exports.

I thought we designed it explicitely in such a way that this is not a problem. It should stop simply because exports happen only daily, and PO files timestamps are also not a reason enough to do an entire commit. What am I missing?

It may well be to do with the fudge factor: the timestamp on the PO file is from the beginning of the import transaction, whereas the timestamp on the bzr commit is from the end of the export—exactly the wrong way around for the check that skips the commit if it risks overwriting changes from another source. So the check "fudges" by a few hours at the risk of doing a few unnecessary commits.

The bouncing data itself is pretty safe: the repeated imports are marked as published so won't overwrite anything in the database, and the repeated exports are skipped if there is any risk of them overwriting anything in the branch. It's just that there may be a few extra imports of identical copies of the file, much as we sometimes saw with the same Ubuntu package being built for multiple architectures. And the POFile timestamps get updated unnecessarily.

This could also be a result of bug #362848: at least we've had someone complain about this though they were manually merging the exported branch into what was later imported.

This is either a duplicate of bug 515051or the other way around.

Here is an example of such a commit:
http://bazaar.launchpad.net/~zeitgeist/zeitgeist/trunk/revision/1356

More useful data in bug 515051.

And my comment: "Probably the simplest solution to this problem is to not update PO file header and date_changed unless at least one translation has changed as well."

Yes, I think I prefer option (b) as well.

Another perfect example of this bug (or bug 515051):

http://bazaar.launchpad.net/~itt-devs/issuetrackertracker/main/revision/217
This is a commit for 4 .po files that have not a single useful modification.

The main branch of the LottaNZB project is also affected: https://code.edge.launchpad.net/~lottanzb/lottanzb/main Unfortunately, the "bouncing" doesn't seem to stop, as nds.po is exported daily without any useful modification. This is quite annoying as it clutters the branch with useless revisions.

dpm's rationale for 'Medium' (Low since we don't use Medium):

This hasn't got directly to do with upstream translations sharing, but it might become more of an issue when upstream sharing gets widely used and translations precedence starts kicking in. It'd be great if upstream maintainers in Launchpad could fully automate the translations process, and having the same branch for translations imports and exports is the way to go. However, they cannot use this feature right now, due to commits being done even if translations have not changed.