Comparison with Git, Mercurial or Darcs?

[Mark Williamson]

> > FWIW, Mercurial does record renames, whereas git does not record them at
> > all.
> 
> Thanks, I didn't know that about Git.
> 
> Just to make sure I understand you about Mercurial: The Bazaar website
> says that when you ask Mercurial to rename, behind the scenes what it
> really does is a delete+add. Is this correct? In other words, Bazaar
> and Darcs are special in that they actually record a rename as a
> rename.

Erk!  I sense that by commenting on features I am likely to be stepping onto 
slightly dangerous ground... ;-)

My *understanding* of git is that renames are not considered especially 
interesting and are never recorded explicitly.  However, various cases of 
renaming can be detected with git commands, when you review the history.  I 
remember Linus posting stuff on this (including his personal argument that 
renames aren't that interesting to record - but obviously not everyone 
agrees!) a while back.  I might be out of date on the specifics but I'd be 
pretty surprised if git had started recording renames in the metadata (as 
opposed to just an add + delete).

What I was stating about Mercurial is that it does *explicitly* record 
renames.  I think I'll stay away from commenting in this e-mail on how this is 
represented internally since I don't understand it well enough.  But the 
history contains an entry saying "blah got renamed to foo".  Unlike git.  So 
if you do it properly (i.e. you checked it in as a rename, not as a 
copy/delete combo) the full and explicit history of renames is available in 
the repository, not just a load of adds and deletes.  I *think* there's an 
additional flag to certain commands that will cause hg to follow these 
renames.

Does that answer your question?

Cheers,
Mark