Re: why is git destructive by default? (i suggest it not be!)

From: Theodore Tso <tytso@mit.edu>
Date: Jun 24, 2008, 22:54 UTC
Message-ID: <20080624225442.GA20361@mit.edu>
In-Reply-To: <FmVFerrNVumRho9GZZwRiHrXV_hb12J_P_hSYUBnFhcCFiMGdtdCrg@cipher.nrlssc.navy.mil>

On Tue, Jun 24, 2008 at 04:42:49PM -0500, Brandon Casey wrote:

> Again, as I mentioned to Boaz, there is really no benefit to reusing
> a single branch name if that is what you are trying to do. The cost
> of branching in git is 41 bytes i.e. nil.

The main reason that I find for reusing a branch name is for my integration branch. I have a script which basically does:

git checkout integration git reset --hard origin git merge branch-A git merge branch-B git merge branch-C git merge branch-D

I suppose I could have avoided the use of git reset with something like this:

git update-index --refresh --unmerged > /dev/null
if git diff-index --name-only HEAD | read dummy; then
	echo "There are local changes; refusing to build integration branch!"
	exit 1
fi
git update-ref refs/heads/integration origin
git checkout integration
git merge branch-A
git merge branch-B
git merge branch-C
git merge branch-D

Instead, I've just learned to be careful and my use of git reset --hard is mainly for historical reasons. But the point is, I can very easily think of workflows where it makes sense to reuse a branch name, most of them having to do with creating integration branches which are basically throwaways after I am done testing or building that combined tree.

							- Ted