"""config_patch deep merge."""

from __future__ import annotations

from shelly_manager.core.config_patch import deep_merge_dict


def test_deep_merge_nested() -> None:
    base = {"mqtt": {"enable": True, "server": "old"}, "sys": {"debug": 0}}
    patch = {"mqtt": {"server": "new", "enable": False}}
    out = deep_merge_dict(base, patch)
    assert out["mqtt"]["server"] == "new"
    assert out["mqtt"]["enable"] is False
    assert out["sys"]["debug"] == 0


def test_deep_merge_adds_key() -> None:
    out = deep_merge_dict({"a": 1}, {"b": {"c": 2}})
    assert out == {"a": 1, "b": {"c": 2}}