Script for removing unused local branches

git-cleanup-branches.sh

#!/usr/bin/env bash

# Cleaner for local branches that have no remotes any more.	
# Not yet pushed local branches are untouched.	
#	
# For convencience, add to ~/.gitconfig as:	
#	
#  [alias]	
#  cleanup-branches = !~/bin/git-cleanup-branches.sh	
#	


set -eu
set -o pipefail


red=$(tput setaf 1; tput bold)
green=$(tput setaf 2; tput bold)
norm=$(tput sgr0)

ask_delete_local_branches() {
  local branches=( "$@" )
  echo
  echo "These branches are going to be ${red}DELETED${norm} locally. Continue? [yN]"
  local answer
  read answer
  if [[ "${answer}" =~ ^(y|Y)$ ]]; then
    git branch -D ${branches[@]}
    echo "${green}✓ Done!${norm}"
    echo
  else
    echo "${red}▩ Aborting${norm}"
  fi
}

stale_local_branches() {
  local -a branches
  #echo "🔎  Searching for stale local branches."
  readarray branches < <(git branch -vv | grep ': gone] ' | grep -v '^* ' | cut -d " " -f 3)
  if [[ "${#branches[@]}" -eq 0 ]]; then
    echo "${green}✓  No stale local branches found. All good.${norm}"
    return
  fi
  # Remove newlines from entries
  branches=("${branches[@]//$'\n'/}")
  # Remove spaces from entries
  branches=("${branches[@]// /}")
  echo "These branches have no remotes any more:"
  printf " - %s\n" "${branches[@]}"
  ask_delete_local_branches "${branches[@]}"
}

# This assumes a release-process that involves "release-" prefixed shared branches.
stale_release_branches() {
  local -a branches
  #echo "🔎  Searching for stale release branches."
  # Shellcheck disable=SC2063
  readarray branches < <(git branch | sed 's/ //g' | grep -v '^* ' | grep '^release-')
  if [[ "${#branches[@]}" -eq 0 ]]; then
    echo "${green}✓  No stale release branches found. All good.${norm}"
    return
  fi
  # Remove newlines from entries
  branches=("${branches[@]//$'\n'/}")
  # Remove spaces from entries
  branches=("${branches[@]// /}")
  echo "You have the following local release branches:"
  printf " - %s\n" "${branches[@]}"
  ask_delete_local_branches "${branches[@]}"
}

stale_local_branches
stale_release_branches

Example output