#!/bin/bash -x
create()
{
        for d in 1 2 3 4 5 6 7 8 9 10; do
                echo "$1"
        done >"$1"
}

. shellopts.sh
set -e

rm -rf mainline subproj
mkdir mainline subproj

cd subproj
git init

create sub1
git add sub1
git commit -m 'sub1'
git branch sub1
git branch -m master subproj

create sub2
git add sub2
git commit -m 'sub2'
git branch sub2

create sub3
git add sub3
git commit -m 'sub3'
git branch sub3

cd ../mainline
git init
create main4
git add main4
git commit -m 'main4'
git branch -m master mainline

git fetch ../subproj sub1
git branch sub1 FETCH_HEAD
git subtree add --prefix=subdir FETCH_HEAD

# this shouldn't actually do anything, since FETCH_HEAD is already a parent
git merge -m 'merge -s -ours' -s ours FETCH_HEAD

create subdir/main-sub5
git add subdir/main-sub5
git commit -m 'main-sub5'

create main6
git add main6
git commit -m 'main6 boring'

create subdir/main-sub7
git add subdir/main-sub7
git commit -m 'main-sub7'

git fetch ../subproj sub2
git branch sub2 FETCH_HEAD
git subtree merge --prefix=subdir FETCH_HEAD
git branch pre-split

split1=$(git subtree split --annotate='*' --prefix subdir --onto FETCH_HEAD --rejoin)
echo "split1={$split1}"
git branch split1 "$split1"

create subdir/main-sub8
git add subdir/main-sub8
git commit -m 'main-sub8'

cd ../subproj
git fetch ../mainline split1
git branch split1 FETCH_HEAD
git merge FETCH_HEAD

create sub9
git add sub9
git commit -m 'sub9'

cd ../mainline
split2=$(git subtree split --annotate='*' --prefix subdir --rejoin)
git branch split2 "$split2"

create subdir/main-sub10
git add subdir/main-sub10
git commit -m 'main-sub10'

split3=$(git subtree split --annotate='*' --prefix subdir --rejoin)
git branch split3 "$split3"

cd ../subproj
git fetch ../mainline split3
git branch split3 FETCH_HEAD
git merge FETCH_HEAD
git branch subproj-merge-split3

cd ../mainline
git fetch ../subproj subproj-merge-split3
git branch subproj-merge-split3 FETCH_HEAD
git subtree pull --prefix=subdir ../subproj subproj-merge-split3