branch-deleter

#!/usr/bin/env bash
set -e

function print_git_tree() {
  git log \
      --graph \
      --no-color \
      --source \
      --all \
      --max-count=5 \
      --max-parents=2 \
      --pretty=oneline \
      | cat
}

function get_parent_commits() {
  git log --pretty=%P --max-count=1 | tr " " "\n"
}

function die () {
    echo >&2 "$1"
    exit "${2:-1}"
}

function get_branches_with_commit_and_suffix() {
  [ -n "${1}" ] || die "1s argument should be a commit id"
  local commit="${1}"

  [ -n "${2}" ] || die "2nd argument should be a suffix"
  local suffix="${2}"

  git branch \
      --no-color \
      --list "*${suffix}" \
      --contains "${commit}" \
    | xargs \
    | tr " " "\n"
}

function delete_branch() {
  [ -n "${1}" ] || die "1st argument should be a branch to delete"
  local branch="${1}"

  echo "    Deleting branch    | ${branch}"
  # git branch --delete --force "${branch}"
  # git push origin --delete --force "${branch}"
}

function delete_branches() {
  [ -n "${1}" ] || die "argument should be names of branches to delete"
  local branches=( "${@}" )
  printf "  Branch to delete     | %s\n" "${branches[@]}"
  echo "--------------------------------------------------------------------------------"
  local branch
  for branch in "${branches[@]}"
  do
    delete_branch "${branch}"
  done
}

function delete_if_necessary() {
  [ -n "${1}" ] || die "1st argument should be a commit id"
  local commit="${1}"

  [ -n "${2}" ] || die "2nd argument should be a branch suffix"
  local suffix="${2}"

  if [[ "${commit}" == "${parent}" ]]
  then
    echo "Skipping commit-id     | ${commit} (is parent)"
    return 0
  fi

  echo "Analyzing commit-id    | ${commit}"
  echo "--------------------------------------------------------------------------------"
  local branches
  mapfile -t branches < <(get_branches_with_commit_and_suffix "${commit}" "${suffix}")
  [ ${#branches} -ge 1 ] && delete_branches "${branches[@]}"
}

function process_parent_commits() {
  local commits
  mapfile -t commits < <(get_parent_commits)
  printf "  Commit to analyze    | %s\n" "${commits[@]}"
  local commit
  for commit in "${commits[@]}"
  do
    echo "================================================================================"
    delete_if_necessary "${commit}" "${suffix}"
  done
  echo "================================================================================="
}

function analyze() {
  [ -n "${1}" ] || die "1st argument should be the suffix"
  local suffix="${1}"

  local parent
  parent="$(git rev-parse HEAD~1)"
  echo "================================================================================"
  echo "Git tree:"
  echo
  print_git_tree
  echo
  echo "================================================================================"
  echo "My commit-id           | $(git rev-parse HEAD)"
  echo "Parent commit-id       | ${parent}"
  echo "--------------------------------------------------------------------------------"
  process_parent_commits
}

analyze "deploy"