npm-release

#!/usr/bin/env bash
#
# This script allows (me) to automate releases of npm libraries with GitHub.
# It relies on `hub` (https://hub.github.com/), `npm version`, and the
# `format-release-notes` script (see `scripts/format-release-notes` in this
# repository).

set -e -o pipefail

NAME='npm-release'
USAGE='[help|major|minor|patch]'
LONG_USAGE="git $NAME help
        print this help message.
git $NAME major
        create a major version.
git $NAME minor
        create a minor version.
git $NAME patch
        create a patch version.
"

source "$(git --exec-path)/git-sh-setup"

REMOTE='origin'
BRANCH=$(git symbolic-ref --short -q HEAD)

require_user_confirmation() {
  read -p "Continue? [y/N] " -n 1 -r
  echo
  if [[ ! "$REPLY" =~ ^[Yy]$ ]]; then
    die "Aborted: user didn't confirm."
  fi
}

npm_release() {
  local type="$1"
  local old_version
  local new_version
  local tmp_release_notes
  local git_log

  cd_to_toplevel

  if [[ ! -f "package.json" ]]; then
    die "Aborted: this script only works with JS and Node projects."
  fi

  require_clean_work_tree rebase "Please commit or stash them."

  if [[ -f "CHANGELOG.md" ]]; then
    echo "Warning: this project contains a CHANGELOG."
    require_user_confirmation
  fi

  old_version=$(node -pe "require('./package.json').version")
  echo "--> found current npm version: $old_version"

  new_version=$(npm --no-git-tag-version version "$type")
  git checkout -- package.json
  # `npm version` also updates the lockfile (if any).
  if [[ -f 'package-lock.json' ]]; then
    git checkout -- package-lock.json
  fi
  echo "--> new $type version will be: $new_version"

  require_user_confirmation

  new_version=$(npm version "$type")
  echo "--> created new npm version: $new_version"

  tmp_release_notes=$(mktemp)
  git_log=$(git log --format="%s" "$old_version"..."$new_version"^)
  git_log=$(format-release-notes "$git_log" "./package.json")
  cat <<EOF > "$tmp_release_notes"
$new_version $(date +'(%Y-%m-%d)')

# git log: $old_version...$new_version^
$git_log

EOF
  # We could pass the message above to `hub release` but sometimes writing good
  # release notes takes time. Let's push and publish the release once we have
  # the notes (we have to push before creating the release, otherwise GitHub
  # will make a tag and we don't want that).
  git_editor "$tmp_release_notes"

  git push --quiet "$REMOTE" "$BRANCH" --tag
  echo "--> pushed changes to GitHub"

  hub release create --edit -F "$tmp_release_notes" "$new_version"
  rm -f "$tmp_release_notes"
}

if [[ "$#" -eq 0 ]]; then
  usage
fi

for arg in "$@"
do
  case "$arg" in
    help)
      git "$NAME" -h ;;
    patch)
      npm_release "patch" ;;
    minor)
      npm_release "minor" ;;
    major)
      npm_release "major" ;;
    *)
      ;;
  esac
done