#!/bin/sh

# Fast-forward all local branches that track a remote branch
#
# Branches with local-only commits are skipped
#
# Usage: git ff-all

set -eu


git fetch --all --prune


current="$(git branch --show-current)"


git for-each-ref --format='%(refname:short) %(upstream:short)' refs/heads/ |
while read -r branch upstream; do

    [ -n "$upstream" ] || continue

    if [ "$branch" = "$current" ]; then
        git merge --ff-only "$upstream" 2>/dev/null \
            || echo "Skipped $branch (not a fast forward)"
        continue
    fi

    git fetch . "$upstream:$branch" 2>/dev/null \
        || echo "Skipped $branch (not a fast forward)"

done