feat(config): add hot-reload via watchfiles (#78)

tests/test_runtime_loader.py

@@ -0,0 +1,36 @@
+from pathlib import Path
+
+import pytest
+
+import takopi.runtime_loader as runtime_loader
+from takopi.config import ConfigError
+from takopi.settings import TakopiSettings
+
+
+def test_build_runtime_spec_minimal(
+    monkeypatch: pytest.MonkeyPatch, tmp_path: Path
+) -> None:
+    monkeypatch.setattr(runtime_loader.shutil, "which", lambda _cmd: "/bin/echo")
+    settings = TakopiSettings.model_validate({"transport": "telegram"})
+    config_path = tmp_path / "takopi.toml"
+    config_path.write_text('transport = "telegram"\n', encoding="utf-8")
+
+    spec = runtime_loader.build_runtime_spec(
+        settings=settings,
+        config_path=config_path,
+    )
+
+    assert spec.router.default_engine == settings.default_engine
+    runtime = spec.to_runtime(config_path=config_path)
+    assert runtime.default_engine == settings.default_engine
+
+
+def test_resolve_default_engine_unknown(tmp_path: Path) -> None:
+    settings = TakopiSettings.model_validate({"transport": "telegram"})
+    with pytest.raises(ConfigError, match="Unknown default engine"):
+        runtime_loader.resolve_default_engine(
+            override="unknown",
+            settings=settings,
+            config_path=tmp_path / "takopi.toml",
+            engine_ids=["codex"],
+        )