[Python-Dev] I am now lost - committed, pulled, merged, what is "collapse"?

[Adrian Buehlmann]

On 2011-03-21 14:40, R. David Murray wrote:
> On Mon, 21 Mar 2011 18:33:00 +0900, "Stephen J. Turnbull" <stephen at xemacs.org> wrote:
>> R. David Murray writes:
>>  > On Mon, 21 Mar 2011 14:07:46 +0900, "Stephen J. Turnbull" <stephen at xemacs.org> wrote:
>>  > > No, at best the DVCS workflow forces the developer on a branch to
>>  > > merge and test the revisions that will actually be added to the
>>  > > repository, and perhaps notice system-level anomolies before pushing.
>>  > 
>>  > hg does not force the developer to test, it only forces the merge.
>>
>> I didn't say any VCS forces the test; I said that the workflow can (in
>> the best case).  That's also inaccurate, of course.  I should have
>> said "require", not "force".
> 
> The workflow in svn "can" "require" this same thing:  before committing,
> you do an svn up and run the test suite.

But with svn you have to redo the test after the commit *if* someone
else committed just before you in the mean time, thereby changing the
preconditions "behind your back", thus creating a different state of the
tree compared to the state in which it was at the time you ran your test.

With a DVCS, you can't push in that situation. At least not without
creating a new head (which would require --force in Mercurial).