"""Tests for atomic_roundtrip_yaml_save() — comment-preserving full-state writes. This helper backs tui_gateway/server.py:_save_cfg(), which used to call yaml.safe_dump and silently clobber user-edited config files on every TUI/gateway setting change (e.g. /personality, /reasoning, /details_mode). """ import os from pathlib import Path from unittest.mock import patch import pytest import yaml class TestAtomicRoundtripYamlSave: @pytest.fixture def config_path(self, tmp_path): return tmp_path / "config.yaml" def test_creates_file_when_missing(self, config_path): from utils import atomic_roundtrip_yaml_save atomic_roundtrip_yaml_save(config_path, {"model": {"default": "test-model"}}) assert config_path.exists() assert yaml.safe_load(config_path.read_text())["model"]["default"] == "test-model" def test_preserves_top_level_key_order(self, config_path): """Existing top-level keys keep their author-intended ordering.""" config_path.write_text( "model:\n" " default: claude-opus-4-7\n" "providers: {}\n" "agent:\n" " max_turns: 90\n" "display:\n" " skin: default\n", encoding="utf-8", ) from utils import atomic_roundtrip_yaml_save # Pass keys in alphabetical order to make sure dict iteration order # in the caller doesn't accidentally rewrite the file alphabetically # (the old yaml.safe_dump bug). atomic_roundtrip_yaml_save( config_path, { "agent": {"max_turns": 100}, "display": {"skin": "mono"}, "model": {"default": "claude-opus-4-7"}, "providers": {}, }, ) text = config_path.read_text(encoding="utf-8") top_keys = [ line.split(":", 1)[0] for line in text.splitlines() if line and not line.startswith(" ") and not line.startswith("#") ] # Comments are stripped from `top_keys` above, so the surviving # order should match the original file, NOT alphabetical. assert top_keys == ["model", "providers", "agent", "display"] def test_preserves_comments(self, config_path): config_path.write_text( "# header comment\n" "model:\n" " # inline note\n" " default: claude-opus-4-7\n" "display:\n" " skin: default # trailing note\n", encoding="utf-8", ) from utils import atomic_roundtrip_yaml_save atomic_roundtrip_yaml_save( config_path, { "model": {"default": "claude-opus-4-7"}, "display": {"skin": "mono"}, }, ) text = config_path.read_text(encoding="utf-8") assert "# header comment" in text assert "# inline note" in text assert "# trailing note" in text assert yaml.safe_load(text)["display"]["skin"] == "mono" def test_preserves_readable_unicode(self, config_path): """Personalities with kaomoji/Chinese characters stay readable on disk instead of getting mangled to \\uXXXX escapes (the headline bug: kawaii/catgirl personality emoji turning into \\u30CE\\uFF65).""" config_path.write_text( "agent:\n" " personalities:\n" " catgirl: \"nya (=^･ω･^=) 你好\"\n" "display:\n" " skin: default\n", encoding="utf-8", ) from utils import atomic_roundtrip_yaml_save atomic_roundtrip_yaml_save( config_path, { "agent": {"personalities": {"catgirl": "nya (=^･ω･^=) 你好"}}, "display": {"skin": "mono"}, }, ) text = config_path.read_text(encoding="utf-8") assert "你好" in text assert "(=^･ω･^=)" in text assert "\\u4f60" not in text assert "\\u30CE" not in text def test_appends_new_keys(self, config_path): config_path.write_text( "model:\n" " default: test-model\n", encoding="utf-8", ) from utils import atomic_roundtrip_yaml_save atomic_roundtrip_yaml_save( config_path, { "model": {"default": "test-model"}, "display": {"personality": "noir"}, "agent": {"system_prompt": "you are noir"}, }, ) result = yaml.safe_load(config_path.read_text(encoding="utf-8")) assert result["model"]["default"] == "test-model" assert result["display"]["personality"] == "noir" assert result["agent"]["system_prompt"] == "you are noir" def test_deletes_keys_missing_from_new_state(self, config_path): """Mirrors the cfg.pop()-then-_save_cfg(cfg) pattern in tui_gateway: e.g. /prompt clear removes custom_prompt entirely.""" config_path.write_text( "model:\n" " default: test-model\n" "custom_prompt: 'old prompt'\n", encoding="utf-8", ) from utils import atomic_roundtrip_yaml_save atomic_roundtrip_yaml_save( config_path, {"model": {"default": "test-model"}}, ) result = yaml.safe_load(config_path.read_text(encoding="utf-8")) assert "custom_prompt" not in result assert result["model"]["default"] == "test-model" def test_overwrites_scalar_value(self, config_path): config_path.write_text( "display:\n" " personality: noir\n", encoding="utf-8", ) from utils import atomic_roundtrip_yaml_save atomic_roundtrip_yaml_save( config_path, {"display": {"personality": "kawaii"}}, ) result = yaml.safe_load(config_path.read_text(encoding="utf-8")) assert result["display"]["personality"] == "kawaii" def test_overwrites_list_wholesale(self, config_path): config_path.write_text( "toolsets:\n" " - one\n" " - two\n", encoding="utf-8", ) from utils import atomic_roundtrip_yaml_save atomic_roundtrip_yaml_save(config_path, {"toolsets": ["three"]}) result = yaml.safe_load(config_path.read_text(encoding="utf-8")) assert result["toolsets"] == ["three"] def test_recurses_into_nested_dicts(self, config_path): """Deep mutations target the matching subtree, not the whole parent. Without this, writing display.personality would drop sibling display.skin. """ config_path.write_text( "display:\n" " skin: default\n" " personality: noir\n" " compact: false\n", encoding="utf-8", ) from utils import atomic_roundtrip_yaml_save atomic_roundtrip_yaml_save( config_path, { "display": { "skin": "default", "personality": "kawaii", "compact": False, } }, ) result = yaml.safe_load(config_path.read_text(encoding="utf-8")) assert result["display"]["skin"] == "default" assert result["display"]["personality"] == "kawaii" assert result["display"]["compact"] is False @staticmethod def _deny_config_reads(config_path): real_open = open def fake_open(file, mode="r", *args, **kwargs): if Path(file) == config_path and "r" in mode: raise PermissionError("denied") return real_open(file, mode, *args, **kwargs) return fake_open def test_refuses_to_overwrite_unreadable_existing_config(self, config_path): """Shares the fail-closed contract with hermes_cli.config.atomic_config_write: an existing-but-unreadable config.yaml (permission error, broken mount) must raise rather than being silently replaced with only new_state.""" original = "model:\n default: test-model\n" config_path.write_text(original, encoding="utf-8") from utils import atomic_roundtrip_yaml_save with patch("builtins.open", side_effect=self._deny_config_reads(config_path)): with pytest.raises(RuntimeError, match="Refusing to overwrite"): atomic_roundtrip_yaml_save(config_path, {"model": {"default": "replacement"}}) assert config_path.read_text(encoding="utf-8") == original def test_restores_owner(self, config_path, monkeypatch): """Mirrors atomic_roundtrip_yaml_update_restores_owner — the write path must preserve the config file's original owner across the temp-file + atomic-replace swap, not just its mode.""" if os.name != "posix": pytest.skip("POSIX-only") config_path.write_text("model:\n default: test-model\n", encoding="utf-8") chown_calls: list[tuple[Path, int, int]] = [] monkeypatch.setattr("utils._preserve_file_owner", lambda _path: (345, 678)) monkeypatch.setattr( "utils.os.chown", lambda path, uid, gid: chown_calls.append((Path(path), uid, gid)), ) from utils import atomic_roundtrip_yaml_save atomic_roundtrip_yaml_save(config_path, {"model": {"default": "updated-model"}}) assert chown_calls == [(config_path, 345, 678)]