Remove local branches with a missing (gone) upstream

git-delete-gone-branches

#!/usr/bin/env bash
# reset environment variables that could interfere with normal usage
unset GREP_OPTIONS

#
# check whether current directory is inside a git repository
#

is_git_repo() {
  git rev-parse --show-toplevel >/dev/null 2>&1
  result=$?
  if test $result != 0; then
    echo >&2 'Not a git repo!'
    exit $result
  fi
}

usage() {
  cat <<EOS
  Usage:
  git delete-gone-branches [-f] [-d]

  -f    - Force deletion of locally unmerged branches
  -d    - Dry run; Only list what will be deleted
EOS
}
is_git_repo

# Use colors, but only if connected to a terminal, and that terminal
# supports them.
if which tput >/dev/null 2>&1; then
    ncolors=$(tput colors)
fi
if [[ -t 1 ]] && [[ -n "$ncolors" ]] && [[ "$ncolors" -ge 8 ]] ; then
    RED="$(tput setaf 1)"
    GREEN="$(tput setaf 2)"
    YELLOW="$(tput setaf 3)"
    BOLD="$(tput bold)"
    NORMAL="$(tput sgr0)"
    BOLD=$(tput bold)
    UNDERLINE=$(tput smul)
    NORMAL=$(tput sgr0)
    COLOR=always
else
    RED=""
    GREEN=""
    YELLOW=""
    BOLD=""
    NORMAL=""
    BOLD=""
    UNDERLINE=""
    NORMAL=""
    COLOR=never
fi


# first we prune origin to ensure our local list of remote branches is up to date
git remote prune origin

while getopts "fd" opt; do
  case $opt in
  f)
    FORCE=true
    ;;
  d)
    DRY_RUN=true
    ;;
  *)
    usage
    exit 1
    ;;
  esac
done

shift $((OPTIND - 1))

GONE_BRANCHES=$(git branch -vv | grep -v "\+\|\*" | grep 'origin/.*: gone]' | awk '{print $1}')

if [ -z "$GONE_BRANCHES" ]; then
  echo "Could not find any local branches that have a gone remote"
  exit 0
fi

if [ "$DRY_RUN" ]; then
  echo -e "Would remove following branches:\n"
  while read -r branch; do
    echo "${YELLOW}  $branch${NORMAL}"
  done <<<"$GONE_BRANCHES"
elif [ "$FORCE" = true ]; then
  echo "$GONE_BRANCHES" | xargs git branch -D
else
  if ! echo "$GONE_BRANCHES" | xargs git branch -d; then
    cat<<-EOF

    ${RED}
    Error: Some local branches are not fully merged.

    If you are sure you want to delete them, run

      ${NORMAL}git delete-gone-branches -f${RED}

    to force their deletion.
    ${NORMAL}

EOF
    exit $?
  fi

fi

# Handy script when following GitFlow and rebasing, since `git branch --merged master` will never list
# a rebased but merged branch (as their commit history differs).