Bash Arguments Example

compare.sh

#!/usr/bin/env bash
set -euo pipefail

usage() {
  echo "Usage: bash compare.sh --head <branch> --base <base_branch> [--dir <dirpath>]"
  exit 1
}

BRANCH_NAME=""
BASE_BRANCH=""
DIR="test"

while [[ $# -gt 0 ]]; do
  case "$1" in
    --head) BRANCH_NAME="$2"; shift 2 ;;
    --base)   BASE_BRANCH="$2";  shift 2 ;;
    --dir)    DIR="$2";          shift 2 ;;
    *)        usage ;;
  esac
done

if [ -z "$BRANCH_NAME" ] || [ -z "$BASE_BRANCH" ]; then usage; fi