Handling unmergeable files -- a call to arms

[Martin Pool]

2009/5/30 Russel Winder <russel.winder at concertant.com>:
> Two thoughts:
>
> Every branch/clone in DVCS is a separate fork of a project, it is not a
> member of a distributed cache. The idea of locking applies only to a
> particular instance of a project.  So there is no need to even
> contemplate any form of distributed file locking.
>
> The whole idea of a global operation across branches/clones in DVCS is a
> complete non-starter.

I think you need to decide how distributed you want this to be,
because various options are possible.  Is there a global lock?  If you
can't reach it do you proceed optimistically, or refuse the change?
Or do you rely on some kind of asynchronous propagation based maybe on
email or bzr commits.

> Bazaar however claims to be able to operate as a drop in replacement for
> Subversion in a centralized repository workflow.  For this workflow, and
> only this workflow, there is the possibility of supporting file locking.

So this suggests that perhaps locking should only work in checkouts of
a central branch, it should make the files physically readonly until
they're locked, and it should keep a list of locked files in the
central branch.  This wouldn't protect distributed branches, but for
such users perhaps that is an advanced case...

-- 
Martin <http://launchpad.net/~mbp/>