Bug#883950: Next steps on "[GPL-3+]" proposal

[Guillem Jover <guillem@debian.org>]

On Thu, 2018-08-02 at 16:45:52 +0800, Markus Koschany wrote:
> Am 02.08.2018 um 16:27 schrieb gregor herrmann:
> > On Thu, 02 Aug 2018 15:13:26 +0800, Markus Koschany wrote:
> >> Nothing will break because no tool besides Lintian checks
> >> debian/copyright for copyright format 1.0 compatibility. 
> > 
> > This is not correct.
> > 
> > There are at least cme (with libconfig-model-dpkg-perl), decopy,
> > probably some of licensecheck/license-reconcile/cdbs (or whatever
> > consumes copyright_hints), dh-make-perl refresh,
> > libdebian-copyright-perl, and probably others which check and/or
> > create/update copyright-format 1.0 files.

libdpkg-perl also has basic parsing support, to stuff could be using
that as a foundation to parse the files.

> Ok, so you have to tell your Perl tools that you can write a license
> paragraph without also having to specify the license in a separate
> standalone license paragraph. This is not really an incompatible change
> but merely a _new_ way to document it. You still have to write new code
> regardless if there is a new copyright format version or not. I don't
> think this is a real issue

The point is that this spec is about a "machine readable format", if
you change the semantics in a backwards incompatible way, then there's
no way for parsers and validators to know whether the file is correct
or not according to the spec (which is generic and should not be tied
to Debian or whether some other package contains what). Parsers might
also start silently failing because the format didn't change, etc. And
users that might want to check whether their files have been updated
might not even be able to easily tell, so this is also making life
for humans more difficult.

> and it would still be better than to shift
> the work to everyone else in existence. We can also just keep allowing
> the boilerplate approach _together_ with the implementation of this
> proposal, so that nobody can complain about it?

As has been mentioned before, you should not need to bump the version
if you don't use the new format; if you do, you have aleady changed
the file anyway and might as well change the version digit.

Thanks,
Guillem