fix: invalidate cached plans and devices on environment reload

src/blueapi/client/client.py

@@ -675,6 +675,10 @@ def reload_environment(
             raise BlueskyRemoteControlError(
                 "Failed to tear down the environment"
             ) from e
+        # Invalidate cached plans/devices so subsequent access reflects the
+        # newly reloaded environment rather than the previous one.
+        self.__dict__.pop("plans", None)
+        self.__dict__.pop("devices", None)
         return self._wait_for_reload(
             status,
             timeout,

tests/unit_tests/client/test_client.py

@@ -350,6 +350,28 @@ def test_reload_environment_failure(
         client.reload_environment()
 
 
+def test_reload_environment_refreshes_cached_plans_and_devices(
+    client: BlueapiClient,
+    mock_rest: Mock,
+):
+    # Prime caches with the original plans and devices.
+    initial_plans = list(client.plans)
+    initial_devices = list(client.devices)
+    assert {p.name for p in initial_plans} == {"foo", "bar"}
+    assert set(initial_devices) == {"foo", "bar"}
+
+    new_plans = PlanResponse(plans=[PlanModel(name="missing")])
+    new_devices = DeviceResponse(devices=[DeviceModel(name="baz", protocols=[])])
+    mock_rest.get_plans.return_value = new_plans
+    mock_rest.get_devices.return_value = new_devices
+    mock_rest.get_environment.return_value = NEW_ENV
+
+    client.reload_environment()
+
+    assert {p.name for p in client.plans} == {"missing"}
+    assert set(client.devices) == {"baz"}
+
+
 def test_abort(
     client: BlueapiClient,
     mock_rest: Mock,