Re: git and time

[Jeff King <peff@peff.net>]

On Wed, Sep 27, 2006 at 10:42:52AM +0200, Andreas Ericsson wrote:

> >>It's true I don't know much about git, what is the difference
> >>between a changeset and a snapshot?  Are you saying timestamps
> >
> >I do not know what Jeff meant by snapshot vs changeset, so I
> >would not comment on this part.
>
> Me neither, but I've seen this distinction before on the mailing-list.
> 
> To my mind, a changeset is the patch that brings some form of data from 
> one state (snapshot) to another. In this respect, git is certainly both 
> snapshot- and changeset-based.

I was talking specifically about the core data structure of git. The
commit object doesn't say "I'm based on commit X, and the deltas are Y."
It says "Here are the complete contents of the tree at this point, and
the previous complete contents were X."

Of course, git often shows changesets (patches, git-whatchanged, etc)
because that's what's useful to users. But the context of the discussion
was fetching commits to a repository. In that case it's important to
note that you're just grabbing the new state (albeit optimizing the
process by skipping things you have) and not "re-committing" changesets
(which is what the OP seemed to think was happening).

-Peff