Create a Release Tag

Require the user to provide the stable release version in exact <major>.<minor>.<patch> form. Do not infer it from package metadata or a branch name, and do not edit package metadata while creating the tag.

RELEASE_VERSION="<user-provided-major.minor.patch>"
if [[ ! "${RELEASE_VERSION}" =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
  echo "Error: release version must be <major>.<minor>.<patch>" >&2
  exit 1
fi
RELEASE_BRANCH="release/$(printf '%s' "${RELEASE_VERSION}" | cut -d. -f1,2)"
RELEASE_TAG="v${RELEASE_VERSION}"

if ! git ls-remote --exit-code --heads upstream "refs/heads/${RELEASE_BRANCH}" >/dev/null; then
  echo "Error: remote release branch ${RELEASE_BRANCH} does not exist on upstream" >&2
  exit 1
fi