# Run single test provided via $1.
# Prints "ok" on success, "FAIL" on failure, and returns the appropriate status code.
run_test() {
  local TEST_SCRIPT=$1
  printf '%s' "Running $(basename "${TEST_SCRIPT}")... "

  # Run test silently.
  # Return 0 on success, 1 on failure.
  if "${TEST_SCRIPT}" > /dev/null 2>&1; then
    echo "ok"
    return 0
  else
    echo "FAIL"
    return 1
  fi
}

# Run all tests in the given directory (specified as $1).
# All .sh tests are executed in sorted order.
# The script reports how many tests failed and exits with non-zero status if any did.
run_tests_in_directory() {
  local DIR=$1
  local failed=0

  echo "== Running tests in directory $(basename "${DIR}") =="

  # Iterate over all .sh files and run them one by one.
  for test_script in $(ls "${DIR}" | sort); do
    case "${test_script}" in
      *.sh)
        if ! run_test "${DIR}/${test_script}"; then
          failed=$((failed + 1))
        fi
        ;;
    esac
  done

  # After running all tests, report overall result.
  if [ "$failed" -ne 0 ]; then
    echo "$failed test(s) failed."
    exit 1
  else
    echo "All tests passed."
  fi
}