clan-cli/tests: improve test helpers for VMs

pkgs/clan-cli/tests/test_vars.py

@@ -1,16 +1,14 @@
 import os
 import subprocess
-from collections import defaultdict
-from collections.abc import Callable
 from io import StringIO
 from pathlib import Path
 from tempfile import TemporaryDirectory
-from typing import Any
 
 import pytest
 from age_keys import SopsSetup
 from fixtures_flakes import generate_flake
 from helpers import cli
+from helpers.nixos_config import nested_dict
 from root import CLAN_CORE
 
 from clan_cli.clan_uri import FlakeId
@@ -20,14 +18,6 @@ from clan_cli.vars.public_modules import in_repo
 from clan_cli.vars.secret_modules import password_store, sops
 
 
-def def_value() -> defaultdict:
-    return defaultdict(def_value)
-
-
-# allows defining nested dictionary in a single line
-nested_dict: Callable[[], dict[str, Any]] = lambda: defaultdict(def_value)
-
-
 def test_get_subgraph() -> None:
     from clan_cli.vars.generate import _get_subgraph