[Python-modules-team] Bug#653650: ipython: Please depend on "python (>= 2.7) | python-argparse"

[Adrian Bunk]

On Sun, Jan 08, 2012 at 01:08:01PM +0530, Ritesh Raj Sarraf wrote:
> Hello Python Team,
> 
> On 12/30/2011 07:11 PM, Ritesh Raj Sarraf wrote:
> > I will be able to look into it only in Jan 2nd week. If there is
> > consensus, please feel free to change it.
> > 
> > On Friday, December 30, 2011, Julian Taylor wrote:
> > 
> >     tags 653650 + wontfix
> >     thanks
> > 
> >     On 12/30/2011 12:29 AM, Adrian Bunk wrote:
> >     > Source: ipython
> >     > Version: 0.11-2
> >     > Severity: normal
> >     >
> >     > The unconditional dependency on python-argparse always pulls in
> >     python2.6.
> >     >
> >     > argparse was included in python2.7
> >     >
> >     > Please change the argparse dependency to
> >     >    python (>= 2.7) | python-argparse
> >     >
> >     > The same change also makes sense for the build dependencies.
> >     >
> >     >
> > 
> >     This will not install python-argparse needed for the 2.6 variants.
> >     The only really satisfying option is adding explicit ipython2.6 packages
> >     which I'm not going to do that as 2.6 will disappear at some point and
> >     packaging is complex enough as is.
> > 
> >     It is my opinion that argparse should revert the 2.6 only change instead
> >     of forcing everyone else to update their packages for no valid reason.
> >     The better way to phase out python-argparse is to wait until python2.6
> >     removal and then let python provide it (like ubuntu did).
> >     To get rid of the harmless pkg-ressources warning one could remove the
> >     2.7 symlinks from the package.
> > 
> > 
> 
> Is there any consensus on this bug report? I only heard one comment from
> Julian. I think if python (>= 2.7) could just provide python-argparse,
> this issue would be resolved.

I'm not sure if there is actually any not too complicated solution that 
handles all cases perfectly.

E.g. your suggestion would leave the problem of not having 
python-argparse installed when using the ipython2.6 program.

What about:
- Depends: "python (>= 2.7) | python-argparse"
  (stop always pulling in python2.6 in wheezy)
- Suggests: python-argparse
  (gives the few people using ipython2.6 a hint what to install)

That would make the dependencies less broad in the common case [1],
while also expressing what is also needed for more obscure funstionality.

> Thanks,
> Ritesh

cu
Adrian

[1] This is equivalent to python2.7 providing python-argparse.

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