On Mon, 2008-06-30 at 12:52 -0700, Jim White wrote:

> I think Mercurial is probably better than Bazaar.

I suspect we are, in the main, going to be arguing personal preference.
Almost all the debate about Bazaar, Mercurial and Git revolves around
performance and personal preferences for the  branching model and the
command set.  Bazaar and Mercurial have improved their performance
markedly over the last year, so all the performance data from over a
year ago is no longer valid.  If performance is to be a driver then new
data will be required.

> I haven't done a direct comparison myself, but my impression so far is 
> that Mercurial is probably a better choice than Bazaar.

See above :-)

> If you consider that projects like OpenJDK, IcedTea, NetBeans, and 
> OpenSolaris have found it the current best choice for distributed 
> version control, then I'm sure you'd agree that at this point 
> alternatives would need to explain why they're better.

MySQL has chosen Bazaar.  Also of course Bazaar is officially a GNU
project -- though this might make some people turn against it for
political reasons!

> There is SVN-to-Hg conversion available, as well as SVN-and-Hg sync.
> 
> http://www.selenic.com/mercurial/wiki/index.cgi/RepositoryConversion
> 
> One of the interesting syncing tools is hgsvn which lets you use Hg on 
> SVN checkouts.  That solves your disconnected operation case and allows 
> a thorough evaluation of Hg before making the switch for the central 
> repository.

I haven't tried this as yet, I must do so.  The trouble with having the
functionality you need in the tool you already use is that it means a
positive effort is needed to try a different tool.

> My best current thought it is too early for a project like Groovy to be 
> concerned about switching to DVCS.  Developers who want to use DVCS 
> should use SVN-and-DVCS-of-personal-choice-synchronization over the next 
> year or so.  Then the tools will then be more mature and the value of 
> switching (if any) will be clear.

Yes and no.  Personally, I would prefer to switch to a DVCS sooner
rather than later, Bazzar for preference but Mercurial or even Git if
that was the majority decision -- actually at the end of the day this is
where Guillaume gets to exercise despotishness, he has the final choice!

The single biggest factor here is "What do Codehaus support?"  I do not
see that there is any need or desire to change hosting from Codehaus to,
say, Launchpad.  Currently Codehaus supports only Subversion.  They are
however looking at Bazaar, Mercurial and Git.  Personally I am not
convinced Git is an option for Windows users not using Cygwin, but by
the time Codehaus have their support for DVCS in place this may have
changed.

I think the issues are definitely tool support for the tools that people
actually need on the platforms people actually use. I think in terms of
operating systems this means Windows, Mac OS X, Ubuntu, Red Hat,
Solaris.  I agree that as of today the GUI tools, and to some extent the
IDE plugins for DVCS support are less mature that the ones for
Subversion.  But again by the time Codehaus have support for DVCS this
will have changed.  Actually I am using the Eclipse Bazaar support all
the time and it works fine.  I suspect the Mercurial and Git support is
equally good.

Of course there is no difficulty for individuals to use Bazaar,
Mercurial or Git as their client to Subversion immediately.  Certainly
this is what I am doing.  Now that Bazaar has the dpush command, I think
people will find it difficult to know from the commit logs whether I
have used Bazaar, Git, or even Subversion to make the commit.  Of course
this only works where a branch is an individual thing, where
collaboration is required more coordination is needed.

Summary:  Until Codehaus officially support a DVCS, all discussion of
the main branch moving to a DVCS are moot.  It is good to discuss so we
know what the issues are, but a decision is moot.  Until then there is
no problem using whatever client people want to use to work with the
Subversion repository.  Only if two people need to collaborate on a
branch is there any issue at all about making a choice of client.  I
would always choose Bazaar, but others may have different views.

-- 
Russel.
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Dr Russel Winder                 Partner

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