From: Antoine Pelisse <apelisse@gmail.com>
Date: Sun, 17 Mar 2013 13:58:59 GMT
Subject: Re: [PATCH] combine-diff: coalesce lost lines optimally
Message-ID: <CALWbr2xWYiFULLDVA7b9WrVtmfdAvZC9SKBHjZE9aRc6kfRMGA@mail.gmail.com>
In-Reply-To: <1363525436-21667-1-git-send-email-apelisse@gmail.com>

> I'm also having a hard time trying it with more than two parents. How I
> am supposed to have more than two parents while octopus merge refuses if
> there are conflicts ?

OK, creating the merge commit myself solves the issue:

git init
>test
git add test
git commit -m initial

seq 100 >test
git commit -m all -a

git checkout -b side1 HEAD^1
seq 1 2 100 >test
git commit -m side1 -a

git checkout -b side2 HEAD^1
seq 1 4 100 >test
git commit -m side2 -a

git checkout -b side3 HEAD^1
seq 1 8 100 >test
git commit -m side3 -a

git checkout -b side4 HEAD^1
seq 1 16 100 >test
git commit -m side4 -a

git checkout master
>test
git add test
TREE=$(git write-tree)
COMMIT=$(git commit-tree $TREE -p master -p side1 -p side2 -p side3 -p
side4 -m merge)
git show $COMMIT

This will work with the basic greedy implementation if all parents are
in this order. But the optimal result will be lost if we change the
order of -p parameters in git-commit-tree.
The patch seems to be correct, always finding the best result (we
always have 100 lines diff) whatever the order of parents.