Script that lists outgoing changes on all branches in the current Git repo, or in Git repos in all immediate subfolders

branch-status.sh

#!/usr/bin/env bash
# This script lists outgoing changes on all branches in the current Git repo.
# If the current folder is not a Git repo, it instead runs on each subfolder.

function get_branch_status {
    # https://stackoverflow.com/a/7774433
    git for-each-ref --format="%(refname:short) %(upstream:short)" refs/heads | \
    while read local remote
    do
        [ -z "$remote" ] && continue
        git rev-list --left-right ${local}...${remote} -- 2>/dev/null >/tmp/git_upstream_status_delta || continue
        AHEAD=$(grep -c '^<' /tmp/git_upstream_status_delta)
        if (( AHEAD > 0 )); then
            echo "- $local $AHEAD commits ahead of $remote"
        fi
    done
    
    STATUS=$(git status -s)
    if [ "$STATUS" ]; then
        echo "- not clean"
    fi
}

# https://stackoverflow.com/a/2180367
inside_git_repo="$(git rev-parse --is-inside-work-tree 2>/dev/null)"

if [ "$inside_git_repo" ]; then
    get_branch_status
else
    echo "No git repository detected. Checking each subfolder:"
    # https://stackoverflow.com/a/26495371
    dirs=($(find . -maxdepth 1 -type d \( ! -name . \)))
    for dir in "${dirs[@]}"; do
        echo $(basename $dir)
        (cd "$dir" && get_branch_status)
    done
fi