Unfold changes into "deeper" branches

git-unfold.sh

#!/bin/bash

# if you have branches like
#  - dev-foo
#  - dev-foo-bar
#  - dev-foo-bar-baz
#
# then go in dev-foo and run "git unfold":
#  - merges the origin branch (dev-foo) into all the others (dev-foo-bar, dev-foo-bar-baz)
#  - fail safe: on conflicts it will undo the merge
#  - no magic: you need to push by hand of course

echo "this needs all changes to be stashed or commited!"
echo ""

origin_branch=$(git rev-parse --symbolic-full-name HEAD)
origin_branch_short=`echo ${origin_branch} | sed -e "s/refs\/heads\///g"`

for target_branch in $(git for-each-ref --format='%(refname)' refs/heads/);
do # unfold on existing target_branch
    if [[ ${target_branch} =~ ^${origin_branch}.* ]] \
    && [[ "${target_branch}" != "${origin_branch}" ]]; then # we found a sub-target_branch

        # refs/heads/foo -> foo
        target_branch_short=`echo ${target_branch} | sed -e "s/refs\/heads\///g"`;

        echo "Merge ${origin_branch_short} into ${target_branch_short} ...";
        git checkout ${target_branch_short} -q

        # merge
        fallback_hash=$(git rev-parse HEAD);
        merge_status=$(git merge ${origin_branch_short} -q);

        if [[ ${merge_status} -ne 0 ]]; then # the merge failed: reset it
            echo -n "FAILED to merge into ${target_branch_short}";
            # fall back
            if [[ $(git reset --hard ${fallback_hash} -q) -eq 0 ]]; then # it's restored
                echo " - has been reseted.";
            else # our fallback failed
                echo " - HAS NOT BEEN RESETED!";
                exit 1;
            fi
        fi

    fi;
done

# hop back
git checkout ${origin_branch_short} -q

echo "";
echo "Remember to push: git push --all";