R SIG Debian - Mar 2017 - Configuration problem installing backport to jessie

I came across this problem moving from the standard jessie package to
the backport:

    $ sudo dpkg --configure r-base-core   
    Setting up r-base-core (3.3.2-1~jessiecran.0) ...
    Preserving user changes to /usr/share/bash-completion/completions/R (renamed
from /etc/bash_completion.d/R)...
    mv: cannot stat ?/usr/share/bash-completion/completions/R?: No such file or
directory
    dpkg: error processing package r-base-core (--configure):
     subprocess installed post-installation script returned error exit status 1
    Errors were encountered while processing:
     r-base-core

I managed to fix this by manually copying the R completion script
/etc/bash_completion.d/R to /usr/share/bash-completion/completions/

I thought I'd best post something about this in case either I haven't
actually fixed it or it means something in the backporting is slightly
wrong with respect to bash completion.

On 2 March 2017 at 14:36, Jim Ottaway wrote:
| I came across this problem moving from the standard jessie package to
| the backport:
| 
|     $ sudo dpkg --configure r-base-core   
|     Setting up r-base-core (3.3.2-1~jessiecran.0) ...
|     Preserving user changes to /usr/share/bash-completion/completions/R
(renamed from /etc/bash_completion.d/R)...
|     mv: cannot stat ?/usr/share/bash-completion/completions/R?: No such file
or directory
|     dpkg: error processing package r-base-core (--configure):
|      subprocess installed post-installation script returned error exit status
1
|     Errors were encountered while processing:
|      r-base-core
| 
| I managed to fix this by manually copying the R completion script
| /etc/bash_completion.d/R to /usr/share/bash-completion/completions/
| 
| I thought I'd best post something about this in case either I haven't
| actually fixed it or it means something in the backporting is slightly
| wrong with respect to bash completion.

Backports are unofficial, and I have limited time.

But if you can work on a test case / improve on this / provide a patch I will
of course integrate it.

Dirk

--
http://dirk.eddelbuettel.com | @eddelbuettel | edd at debian.org

>>>>> Dirk Eddelbuettel <edd at debian.org> writes:
> Backports are unofficial, and I have limited time.
> But if you can work on a test case / improve on this / provide a patch I
will
> of course integrate it.
Thank you for your reply.

I have very limited time as well, and limited knowledge of installation
scripts in Debian packages. So if anyone on this list has contact info
for whoever looks after the backport, let me know and I'll send this
info to them.

Yours sincerely,
-- 
Jim Ottaway

Hi,

Am Donnerstag, 2. M?rz 2017, 14:36:31 schrieb Jim
Ottaway:
> I came across this problem moving from the standard jessie package to
> the backport:
> 
>     $ sudo dpkg --configure r-base-core
>     Setting up r-base-core (3.3.2-1~jessiecran.0) ...
I am the one building and uploading those backports to Debian stable to 
CRAN...
>     Preserving user changes to /usr/share/bash-completion/completions/R
> (renamed from /etc/bash_completion.d/R)... 
> mv: cannot stat
> ?/usr/share/bash-completion/completions/R?: No such file or directory
> dpkg:
> error processing package r-base-core (--configure):
>      subprocess installed post-installation script returned error exit
> status 1 Errors were encountered while processing:
>      r-base-core
OK, to check this, I just installed R from jessie on a fresh jessie 
installation, and upgraded using the CRAN backports. I get

Configuration file '/etc/bash_completion.d/R'
 ==> Deleted (by you or by a script) since installation.
 ==> Package distributor has shipped an updated version.
   What would you like to do about it ?  Your options are:
    Y or I  : install the package maintainer's version
    N or O  : keep your currently-installed version
      D     : show the differences between the versions
      Z     : start a shell to examine the situation
 The default action is to keep your current version.
*** R (Y/I/N/O/D/Z) [default=N] ? 

"Deleted (by you or by a script) since installation" points to a
packaging
problem, as I have not touched anything in this installation. Indeed, there is 
no file /etc/bash_completion.d/R in the system.

I accepted the default (keep the currently-installed version) and the 
installation proceeded without errors.

Then I purged r-base and r-base-core, installed R 3.1.1 from jessie again, and 
repeated the upgrade, selecting the other option (install the package 
maintainers version).

Then I get:

Installing new version of config file /etc/bash_completion.d/R ...
Preserving user changes to /usr/share/bash-completion/completions/R (renamed 
from /etc/bash_completion.d/R)...
mv: cannot stat ?/usr/share/bash-completion/completions/R?: No such file or 
directory
dpkg: error processing package r-base-core (--configure):
 subprocess installed post-installation script returned error exit status 1

which is exactly the error you got!
> I managed to fix this by manually copying the R completion script
> /etc/bash_completion.d/R to /usr/share/bash-completion/completions/
Thanks for sharing the workaround.
> I thought I'd best post something about this in case either I
haven't
> actually fixed it or it means something in the backporting is slightly
> wrong with respect to bash completion.
Somehow the R 3.3.2 package deletes /etc/bash_completion.d/R before it tries 
to move it. Then, if you select to keep your current version, this current 
version is empty which leads to the error.

According to the changelog, debian/r-base-core.maintscript was introduced to 
fix

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=840506

It seems that the interaction of the maintscript and dh_bash-completion is 
error-prone. Admins should not be bothered by a question about bash completion 
when they did not touch the configuration.

On the other hand, the backports install fine when accepting the default 
option, and we have a workaround for the other case.

Hopefully we can do better when packaging/backporting R 3.3.3, expected for 
next week.

Kind regards,

Johannes
> 
> _______________________________________________
> R-SIG-Debian mailing list
> R-SIG-Debian at r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-debian

That all looks exactly as it happened for me.

Thank you for going through the steps like that: next time I find a
problem like this I'll have a better idea how to track it down and
propose a fix rather than merely reporting the problem.

And thanks for looking after the backporting: I wish to have a stable
Debian but with up to date R, so it's ideal for me.

Yours sincerely,
-- 
Jim Ottaway

On 3 March 2017 at 08:51, Johannes Ranke wrote:
| "Deleted (by you or by a script) since installation" points to a
packaging
| problem, as I have not touched anything in this installation. Indeed, there is
| no file /etc/bash_completion.d/R in the system.

The default location for these files changed, I finally complied.

But nobody tests this for backports -- so if you or Jim could cook up one or
two changes to the postinst etc files (ie /var/lib/dpkg/info/r-base-core.p*
once installed) it would help for your case.

Dirk

-- 
http://dirk.eddelbuettel.com | @eddelbuettel | edd at debian.org