[Numpy-discussion] Moving away from svn ?

[David Cournapeau]

On Jan 5, 2008 3:58 AM, Fernando Perez <fperez.net at gmail.com> wrote:
> On Jan 4, 2008 11:45 AM, Ondrej Certik <ondrej at certik.cz> wrote:
>
> > David is 100% right, I fully support this. I would be just repeating
> > what he says.
> >
> > Charles actually said another point in favor of Mercurial - it works
> > on Windows (at least people say so), while git not that much (at least
> > people say so). I never use Windows myself, so I don't know.
>
> FWIW, we (ipython) have also gone around a few times on this, and
> would like (at some point to switch to a DVCS as well).  I think the
> benefits are many, so I won't rehash it here, others have done it
> well.
>
> One point that hasn't been mentioned is how useful a DVCS is when
> doing dev sprints: people can work and sync off their own private
> repos without touching SVN, with lots and lots of cross-developer
> information flow that doesn't affect the main server or even other
> devs.  In fact, when doing sprints I always end up making a local hg
> repo just for that purpose, and then committing back to svn upstream
> at the end of the sprint.
>
> As much as git looks really good, the Windows issue is, I think, a
> deal killer: last I checked support was poor, and I think our core dev
> tools should be truly, 100% cross-platform without any discrimination
> (kinda-sorta-works on platform X isn't enough).

I agree. This is not enough, but for me, the following are non negotiable:
 - the tool must work on unix, mac os X and windows
 - the tool must be open source.

I guess everyone agrees on those points anyway.

>
> My vote so far is for hg, for performance reasons but also partly
> because sage and sympy already use it, two projects I'm likely to
> interact a lot with and that are squarely in line with the
> ipython/numpy/scipy/matplotlib world.  Since they went first and made
> the choice, I'm happy to let that be a factor in my decision.  I'd
> rather use a tool that others in the same community are also using,
> especially when the choice is a sound one on technical merit alone.
>

I understand the "sumpy uses it" reason, it is definitely a factor.
But I would rather have a more thorough study on the merits of each
system. For example, being a user of bzr for a year and a half now, I
think I have a pretty good idea on how it works, and its advantages.
We could then decide on a set of attributes to compare, and people who
knows about one tool could then tell about it.

Performances-wise, hg and bzr really are comparable nowadays for
common, local operations. I don't think it is a relevant parameter for
the hg vs bzr choice anymor, specially for scipy/numpy which are small
projects (I have bzr imports of scipy and scikits, so I can give some
numbers if you need them). Third party tools, special abilities (svn
import, storage efficiency, special commands, etc...) are more
important I think

David