Re: [PATCH] provide a new "theirs" strategy, useful for rebase --onto

Junio C Hamano wrote:

Paolo Bonzini [off-list ref] writes:

quoted

   #! /bin/sh
   # git-merge-after-amend <branch>
   #
   # Makes it possible to do a fast-forward merge of <branch>
   # into HEAD, assuming that the first diverging commit of <branch>
   # is an --amend'ed version of the first diverging commit of HEAD.

Can this strong special case limitation "only the first one can be the
amend" somehow be loosened?

Well, the point of the exercise is to split a *single* commit into a 
"base" commit (already available, possibly on another branch) and a 
"delta" (the amending, transformed into an independent commit whose 
parent is the "base").  Indeed you can do that for any commit.

The script uses the "git-merge-base" to compute the "base", and takes 
the following commit (on the path to HEAD) as the "delta".  That's what 
add the restriction.  You can definitely make a two-argument variation 
that, given arguments "B C" and history

     o--B     (it is irrelevant if B and C have common parents)

     o--o--C--D--E    HEAD

makes

     A--B--C'--D--E

Even in that case, I would make the script (which anyway is obviously 
not meant to be included in git, it's a commodity script) accept both 
variations: one-argument to do the special case, and two-arguments to 
generically split a commit into a base provided by the user + a delta.

Paolo