Version string to auto-sync an Ubuntu delta (maysync1 vs ~willsync1)

[Lukas Märdian]

Hi all!

We had an interesting discussion with @enr0n and @brian-murray recently, 
about which version string to choose if we want an Ubuntu package 
(+delta) to be auto-synced, without the need for a manual merge. The 
results might be of interest for the broader Ubuntu developer community!

The context was a sponsoring request for "gnudatalanguage" [0] but the 
outcome applies to and can be useful all over the archive.

Initially a version of "1.0.1-3willsync1" was suggested, as the fix was 
already committed in Debian (Salsa) but not yet uploaded and we had some 
precedence about the "willsyncX" version in the archive [1]. We wanted 
it to sync automatically, as soon as the upload happens in Debian and 
therefore avoided an "ubuntuX" version string, as this would block an 
auto-sync [2]. BUT: "-3willsync1" > "-3ubuntu1" or another potential, 
future "ubuntuX" version, so if we'd need to add another patch, which 
might not necessarily auto-sync, we cannot override the "willsync1" 
version with an "ubuntuX" version. That's a problem and could lead to 
ugly version strings.



We needed a version that does not contain the word "ubuntu", so it can 
be auto-synced, once the committed patch is uploaded into Debian. But at 
the same time we needed it to be bigger than the current version 
(1.0.1-3build2) and wanted it to be smaller than a potential, future 
"1.0.1-3ubuntu1" version. We came up with the following:


1.0.1-3build2 < 1.0.1-3maysync1 < 1.0.1-3ubuntu1 => 1.0.1-3maysync1


So I'd like to suggest that anybody in a similar situation should be 
using a "maysync1" revision, in favor of "willsync1".

Cheers,
    Lukas


PS: "1.0.1-3~willsync1" might have been another option, but that's in 
conflict (i.e. smaller than) the current "-3build2" version string.


[0] https://pad.lv/1973377
[1] $ apt search . | grep "sync[0-9]"
[2] https://git.launchpad.net/ubuntu-archive-tools/tree/auto-sync#n566