XPost: linux.debian.bugs.dist
From: guillem@debian.org

Control: forcemerge 330256 -1

Hi,

On Tue, 2024-05-28 at 14:28:49 -0700, Josh Triplett wrote:

tags 1006655 + patch
thanks

I've attached a patch implementing an rm_conffile_if_unmodifed command
for dpkg-maintscript-helper, as well as a declarative version for debian/conffiles.

I've included documentation and tests for both.

Using this has the same effect as rm_conffile if the file is unmodified. However, if the file is modified, this leaves the file in place under
the existing name (treating it as an obsolete conffile so that it still
gets removed if purging the package).

Thus, unlike rm_conffile, this version is useful for packages that still support reading the configuration file if present, and thus don't want
to move existing modified configuration aside with a .dpkg-bak suffix, because that'll prevent the modified configuration from being used.

As I mentioned in #822462, I think the default should be changed instead
to do this. I sat yesterday to see how much this would imply code wise
and ended up with a smallish patch, which then required adapting few test cases. I also added a new --assert-unmodified-obsolete-conffile-removal (although I'm not entirely happy with such a long name). I'd still need
to add a few more tests for downgrades, but otherwise it seems to work
fine.

Being this such a behavior change, although it seems pretty safe to
me, I think it would still deserve to be discussed in debian-dpkg and debian-devel. The only problematic thing that comes to mind, is that
it will be harder to spot conffiles that need to be marked as remove-on-upgrade, as test systems would automatically get rid of
unmodified conffiles.

Will try to add the missing tests and push this into a branch tomorrow,
and then try to start a thread on the mailing lists during the week or so.

Regards,
Guillem

--- SoupGate-Win32 v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)