Add childprotection module (#1141)

When turned on, rotating the thermostat will not change the target
temperature.

kasa/tests/fakeprotocol_smart.py

@@ -430,6 +430,16 @@ class FakeSmartTransport(BaseTransport):
         info["get_preset_rules"]["states"][params["index"]] = params["state"]
         return {"error_code": 0}
 
+    def _update_sysinfo_key(self, info: dict, key: str, value: str) -> dict:
+        """Update a single key in the main system info.
+
+        This is used to implement child device setters that change the main sysinfo state.
+        """
+        sys_info = info.get("get_device_info", info)
+        sys_info[key] = value
+
+        return {"error_code": 0}
+
     async def _send_request(self, request_dict: dict):
         method = request_dict["method"]
 
@@ -437,7 +447,7 @@ class FakeSmartTransport(BaseTransport):
         if method == "control_child":
             return await self._handle_control_child(request_dict["params"])
 
-        params = request_dict.get("params")
+        params = request_dict.get("params", {})
         if method == "component_nego" or method[:4] == "get_":
             if method in info:
                 result = copy.deepcopy(info[method])
@@ -518,6 +528,8 @@ class FakeSmartTransport(BaseTransport):
             return self._edit_preset_rules(info, params)
         elif method == "set_on_off_gradually_info":
             return self._set_on_off_gradually_info(info, params)
+        elif method == "set_child_protection":
+            return self._update_sysinfo_key(info, "child_protection", params["enable"])
         elif method[:4] == "set_":
             target_method = f"get_{method[4:]}"
             info[target_method].update(params)

kasa/tests/smart/modules/test_childprotection.py

@@ -0,0 +1,43 @@
+import pytest
+
+from kasa import Module
+from kasa.smart.modules import ChildProtection
+from kasa.tests.device_fixtures import parametrize
+
+child_protection = parametrize(
+    "has child protection",
+    component_filter="child_protection",
+    protocol_filter={"SMART.CHILD"},
+)
+
+
+@child_protection
+@pytest.mark.parametrize(
+    ("feature", "prop_name", "type"),
+    [
+        ("child_lock", "enabled", bool),
+    ],
+)
+async def test_features(dev, feature, prop_name, type):
+    """Test that features are registered and work as expected."""
+    protect: ChildProtection = dev.modules[Module.ChildProtection]
+    assert protect is not None
+
+    prop = getattr(protect, prop_name)
+    assert isinstance(prop, type)
+
+    feat = protect._device.features[feature]
+    assert feat.value == prop
+    assert isinstance(feat.value, type)
+
+
+@child_protection
+async def test_enabled(dev):
+    """Test the API."""
+    protect: ChildProtection = dev.modules[Module.ChildProtection]
+    assert protect is not None
+
+    assert isinstance(protect.enabled, bool)
+    await protect.set_enabled(False)
+    await dev.update()
+    assert protect.enabled is False