git-describe-semver.sh

#!/usr/bin/env bash

set -o errexit -o nounset -o pipefail

# Bash installation script for https://github.com/choffmeister/git-describe-semver utility
# for use in --workspace_status command. We can't carry a bazel run dependency on this tool
# since we need to use it in --workspace_status.

git_describe_semver_url_base="https://github.com/choffmeister/git-describe-semver/releases/download"
git_describe_semver_version=0.3.9

os=$(uname -s)
readonly os

arch=$(uname -m)
readonly arch

case "$os" in
  Darwin*)
    case "$arch" in
      x86_64*)
        url="${git_describe_semver_url_base}/v${git_describe_semver_version}/git-describe-semver_${git_describe_semver_version}_darwin_amd64.tar.gz"
        ;;

      arm64*)
        url="${git_describe_semver_url_base}/v${git_describe_semver_version}/git-describe-semver_${git_describe_semver_version}_darwin_arm64.tar.gz"
        ;;

      *)
        echo "Unsupported Darwin arch"
        exit 1
        ;;
    esac
    ;;

  Linux*)
    case "$arch" in
      x86_64*)
        url="${git_describe_semver_url_base}/v${git_describe_semver_version}/git-describe-semver_${git_describe_semver_version}_linux_amd64.tar.gz"
        ;;

      arm64*)
        url="${git_describe_semver_url_base}/v${git_describe_semver_version}/git-describe-semver_${git_describe_semver_version}_linux_arm64.tar.gz"
        ;;

      *)
        echo "Unsupported Linux arch"
        exit 1
        ;;
    esac
    ;;

  *)
    echo "Unsupported OS"
    exit 1
    ;;
esac

cache_dir="$(cd $(dirname "$0"); pwd)/.cache/git-describe-semver-v${git_describe_semver_version}"
readonly cache_dir
mkdir -p "$cache_dir"

git_describe_semver_tarball="$cache_dir/git-describe-semver.tar.gz"
git_describe_semver_binary="$cache_dir/git-describe-semver"

if [ ! -f "$git_describe_semver_tarball" ]; then
    rm -f "$git_describe_semver_binary"
    curl -L "$url" -o "$git_describe_semver_tarball" 2> /dev/null
fi

if [ ! -f "$git_describe_semver_binary" ]; then
  tar -xf "$git_describe_semver_tarball" -C "$cache_dir"
fi

exec "$cache_dir/git-describe-semver" "$@"