Re: git-svn and huge data and modifying the git-svn-HEAD branch directly

From: Martin Langhoff <martin.langhoff@gmail.com>
Date: Feb 28, 2006, 00:58 UTC
Message-ID: <46a038f90602271658h35623e58o7237a1703e6f4abd@mail.gmail.com>
In-Reply-To: <Pine.LNX.4.64.0602271634410.22647@g5.osdl.org>

On 2/28/06, Linus Torvalds <torvalds@osdl.org> wrote:

Show 10 quoted lines

> On Tue, 28 Feb 2006, Martin Langhoff wrote:
> > git-svn-HEAD "moves" so it's really a bad idea to have it as a tag.
> > Nothing within core git prevents it from moving, but I think that
> > porcelains will start breaking. Tags and heads are the same thing,
> > except that heads are expected to change (specifically, to move
> > forward), and tags are expected to stand still.
>
> Well, I wouldn't say that tags are expected to stand still. Some kinds of
> tags are expected to move: a "this is the last tested version" tag would
> be expected to move with testing.

Alrighty... in my git projects where things like these matter, my "latest tested" and "current in production" refs are actually in refs/heads.

> That said, the movement is _different_ from a branch. A branch is expected
> to move _with_ development, while a tag is expected to either stay the
> same, or move _after_ development.

Grumble. I'd say a head is expected to reliably move _forward_... "with" development, yes, but definitely forward. In my book a tag wouldn't move, but if I take your word for it, then a tag can perhaps change arbitrarily?

I'm not sure how much support we have in porcelains for "tracking" a tag if it starts changing. Right now I think we'd find all sorts of problems, we'd need to think carefully what moving tags means for porcelains.

> Or something even more specific, like "refs/svn-tracking/". Git
> shouldn't care - all the tools _should_ work fine with any subdirectory
> structure.

I think the moving-forward (therefore is trackable) vs stays reliably in place distinction *is* useful. "Moves randomly" may also be useful, but it should get a different treatment, because it's not "trackable".

Not that git and porcelains can't deal with all this stuff. But if there is a clear convention then porcelains can be smart and refuse to commit to the wrong place... it'd be a bit of a UI enhancement perhaps?

martin