Delete Stale Branches

delete-stale-branches.sh

#!/usr/bin/env bash

usage() { 
  echo "Usage: $0 [-y] [-l]" 1>&2; 
  echo "Uses dry run by default, specify -y to actually delete" 1>&2; 
  echo "Use -l to delete local branches" 1>&2; 
  echo "Assumes the main branch is called 'main'" 1>&2; 
  echo "Set main branch using git config core.main-branch 'main'" 1>&2; 
  exit 1;
}

DRYRUN="--dry-run"
DELETELOCAL=""

while getopts "ylh" opt; do
  case $opt in
    y) DRYRUN="";;
    l) DELETELOCAL="y";;
    h) usage;;
  esac
done

# Prune local "cache" of remote branches first.
git fetch --prune origin

# Get main branch name.
MAIN=$(git config --get core.main-branch)
if [ -z "$MAIN" ]; then
  MAIN="main"
fi

echo -e "Main brach is \033[1;33m$MAIN\033[0m"

MAINEXISTS=$(git ls-remote --heads origin $MAIN)
if [[ -z "$MAINEXISTS" ]]; then
  echo -e "\033[0;31mMain branch not found on remote\033[0m"
  usage
fi

if [ -n "$DRYRUN" ]; then
  echo -e "\033[1;33mDry run is active\033[0m"
fi

# Delete merged to main branches.
mergedBranches=$(git branch -r --merged origin/$MAIN | egrep -v "(^\\*|main|master|develop|dev|staging|sandbox)" | cut -d/ -f2-)
if [ -n "${mergedBranches}" ]; then
  echo -e "\033[0;32mDeleting merged branches ...\033[0m"
  git push $DRYRUN --delete origin ${mergedBranches}
fi

# Get branches with last (cherry picked) commit older than 5 months.
echo -e "\033[0;32mSearching for stale branches ...\033[0m"
staleTimestamp=$(date -d "now - 5 months" +"%s")
maybeStaleTimestamp=$(date -d "now - 2 weeks" +"%s")
notMergedBranches=$(git branch -r --no-merged origin/$MAIN | grep "^  origin/" | egrep -v "(^\\*|main|master|develop|dev|staging|sandbox)")
branchesToDelete=""
branchesToReview=""
for branch in ${notMergedBranches}; do
  lastCommitInfo=$(git cherry origin/$MAIN ${branch} | grep -v "^-" | cut -d" " -f2 | xargs git show --format="%H|%ct|%cr|%an" --quiet | grep -v "^$(git rev-parse HEAD)" | tail -1)
  lastCommitTimestamp=$(echo "${lastCommitInfo}" | cut -d"|" -f2)
  if [ -z "${lastCommitTimestamp}" ] || [ ${lastCommitTimestamp} -lt ${staleTimestamp} ]; then
    branchesToDelete+=" ${branch#origin/}"
  elif [ ${lastCommitTimestamp} -lt ${maybeStaleTimestamp} ]; then
    branchesToReview+="${branch#origin/}|${lastCommitInfo}"$'\n'
  fi
  echo -n .
done

echo # for new line after dots

# Delete branches with last (cherry picked) commit older than 5 months.
if [ -n "${branchesToDelete}" ]; then
  echo -e "\033[0;32mDeleting stale branches ...\033[0m"
  git push $DRYRUN --delete origin ${branchesToDelete}
else
  echo -e "\033[0;32mNo stale branches found.\033[0m"
fi

# List stale branches.
echo -e "\033[1;33mBranches to review (may be stale):\033[0m"
echo "${branchesToReview}" | sort -t"|" -k5 | awk -F"|" 'NF {print $5 " changed branch \"" $1 "\" in project \"'${PWD##*/}'\" " $4}'

# Delete local merged branches.
if [ -n "$DELETELOCAL" ]; then
  if [ -n "$DRYRUN" ]; then
    echo -e "\033[1;33mWill delete local merged branches\033[0m"
    git branch --merged | egrep -v "(^\\*|main|master|develop|dev|staging|sandbox)"
  else
    echo -e "\033[1;33mDelete local merged branches\033[0m"
    git branch --merged | egrep -v "(^\\*|main|master|develop|dev|staging|sandbox)" | xargs git branch -d #
  fi
fi