From: Ingo Molnar <mingo@elte.hu>
Date: Wed, 23 Jul 2008 14:56:22 GMT
Subject: Re: q: faster way to integrate/merge lots of topic branches?
Message-ID: <20080723145622.GA23440@elte.hu>
In-Reply-To: <76718490807230747w5d0350b8v6feba00fb8837617@mail.gmail.com>


* Jay Soffian <jaysoffian@gmail.com> wrote:

> > CACHE=$MERGECACHE/$HEAD_SHA1/$BRANCH_SHA1
> >
> > [ -f "$CACHE" -a "$CACHE" -nt .git/refs/heads/$BRANCH_SHA1 ] && {
> 
> Shouldn't this be:
> 
> [ -f "$CACHE" -a "$CACHE" -nt .git/refs/heads/$BRANCH ] && {
> 
> ?

yeah, i just figured it out too ... the hard way :)

Updated script below. This works fine across resets in the master 
branch.

While it's fast in the empty-merge case, it's not as fast as i'd like it 
to be in the almost-empty-merge case.

	Ingo

--------------{ git-fastmerge }-------------------->
#!/bin/bash

usage () {
  echo 'usage: tip-fastmerge <refspec>..'
  exit -1
}

[ $# = 0 ] && usage

BRANCH=$1

MERGECACHE=.git/mergecache

[ ! -d $MERGECACHE ] && { mkdir $MERGECACHE || usage; }

HEADREF=.git/$(cut -d' ' -f2 .git/HEAD)

HEAD_SHA1=$(git-log -1 --pretty=format:"%H")
BRANCH_SHA1=$(git-log -1 --pretty=format:"%H" $BRANCH)

CACHE=$MERGECACHE/$HEAD_SHA1/$BRANCH_SHA1

[ -f "$CACHE" -a "$CACHE" -nt "$HEADREF" ] && {
# echo "merge-cache hit on HEAD <= $1"
  exit 0
}

git-merge $1 && {
  mkdir -p $(dirname $CACHE)
  touch $CACHE
}