[debhelper-devel] Bug#798414: Bug#798414: debhelper: empty support file should imply no-op

[Michael Banck]

On Wed, Sep 09, 2015 at 07:48:43AM +0200, Niels Thykier wrote:
> Control: tags -1 moreinfo
> 
> On 2015-09-09 00:52, Michael Banck wrote:
> > Package: debhelper
> > Version: 9.20150101
> > Severity: wishlist
> > 
> > Dear Maintainer,
> > 
> > I had the case of one upstream package shipping a useless ChangeLog file
> > (basically having "check Github" as content).  dh_installchangelogs
> > installs this file automatically, unless I manually intervene.  The only
> > way to do so seems to be to add additional targets to debian/rules.  
> > 
> > My original idea of just shipping an empty debian/<package>.changelog
> > file did not work, debhelper aborted with an error.
> > 
> > So I'm filing this wishlist bug for consideration of empty support files
> > to imply no-ops rather than errors.  I think that would be an elegant
> > design, but I am not sure whether this is in line with dh in general.
> > 
> > 
> > Michael
> > 
> > [...]
> 
> Hi Michael,
> 
> Thanks for your suggestion.
> 
> Unfortunately, I am not convinced it can be trivially implemented as
> such. In particular, please note that you probably do not want
> dh_installchangelogs to be a (complete) no-op as it also installs the
> Debian changelogs.

Right, I've since realized that.
 
> A couple of notes:
> 
>  * debian/<pkg>.changelog is *not* the debhelper config file for
>    dh_installchangelogs, but rather the *actual* changelog to put
>    in that package.
>    - That is why it breaks when it is empty.

Hrm, I see. Is this supposed to be a package-specific Debian changelog
then?
 
>  * A completely empty override target in debian/rules will make the
>    command "disappear" from the sequence.  Note that is must not
>    contain a "comment-command"[1].
>    - Useful for skipping other "dh_*"-commands, but maybe not
>      dh_installchangelogs.
> 
>  * Beyond dh_installchangelogs: Some commands have side-effects
>    beyond their arguments and their helper files.
> 
> So far, the best solution I can come up with is to use the -X feature.

Right.