Re: [PATCH] git-merge: add option --no-ff

On 9/17/07, Johannes Schindelin [off-list ref] wrote:

Hi,

On Mon, 17 Sep 2007, Lars Hjemli wrote:

quoted

On 9/17/07, Johannes Schindelin [off-list ref] wrote:

quoted

But then, I do not use svn branches here, and that might be the problem?

Probably. The case I'm trying to solve is:
  -git-svn branch A is merged into git-svn branch B
  -A is a fast-forward of B

This might look unrealistic, but it happened to me today when I wanted
to merge a feature-branch into a relase-branch. The release-branch had
previously been merged into the feature-branch (to get a few
bugfixes), but the release-branch had not changed since this merge. So
when merging the feature-branch into the release-branch it just
fast-forwarded, leaving me with an 'un-dcomittable' release-branch. I
obviously could have done the merge in subversion (haha!), but doing
it in git preserves the correct history.

Btw: I have redone the merge with --no-ff, and dcommit then worked
like a charm ;-)

Yep, I can see that now.

But maybe there is a better method to detect the latest svn id, by not
only looking up the svn ids, but making sure that they come from the
current branch?

Actually, I looked into this last week (my --upstream rants), and I
guess git-svn could use the --track information in .git/config (if
present) as a sanity check when resolving the upstream. But this would
still make the subversion history look like crap after a fast-forward
merge of the kind I was messing with today. It was logically a merge,
but if dcommit had worked 'correctly' it would have created ~150 new
revisions in the release-branch instead of the single merge commit.

(I'm happily unaware of git-svn's internals, so that might not be
feasible... But I think that it might be worth fixing that for the git-svn
idiot like me, since I would never guess that I have to specify --no-ff
when working on branches that come from git-svn...)

In the normal cases there is no need for --no-ff, only in degenerated
cases like the one I stumbled upon today ;-)

I'll resend the patch with a link from merge-options.txt to
git-svn.txt and try to describe (in git-svn.txt) when to use --no-ff.

-- 
larsh