rm_old_branches.sh

#!/usr/bin/env bash

rm_old_branches() {
  # rm_old_branches
  #
  # Quo corporis ea tempore quisquam ducimus. At tempore nemo qui et distinctio
  # consectetur quia quaerat. Et quia aliquam ad sed aut libero.
  #
  # Non deleniti eligendi est explicabo harum qui. Consequatur et assumenda
  # aperiam eligendi ut error odit aut. In ut dolores nobis harum facilis vero
  # nemo ratione. Quod tempore neque nam cupiditate et. Et maxime aut rerum.

  local branch_age_limit=$((60 * 60 * 24 * 1))
  local current_branch="$(git branch | grep '^\*' | cut -c 2-)"

  for branch in $(git branch | cut -c 2-); do
    git checkout -q "$branch"

    local last_commit_iso8601="$(git log -n 1 --format='%ci' | cut -c 1-19 | sed -E 's/ /T/g')"
    local last_commit_ts="$(gdate -d "${last_commit_iso8601}" +%s)"
    local now_ts="$(gdate +%s)"

    local diff=$(($now_ts - $last_commit_ts))

    if [ "$diff" -gt "$branch_age_limit" ]; then
      echo "$branch should be deleted."
    fi
  done

  git checkout -q $current_branch
}

rm_old_branches