SAR-276 Lint fixes. Simplified task_result

src/ska_tango_base/base/base_device.py

@@ -433,7 +433,6 @@ class SKABaseDevice(Device):
             device.set_change_event("status", True, True)
             device.set_archive_event("status", True, True)
 
-            # Long running command attributes
             device.set_change_event("longRunningCommandsInQueue", True, True)
             device.set_archive_event("longRunningCommandsInQueue", True, True)
             device.set_change_event("longRunningCommandIDsInQueue", True, True)
@@ -1162,9 +1161,7 @@ class SKABaseDevice(Device):
 
         :return: ID, ResultCode, result.
         """
-        if not self.component_manager.task_result:
-            return []
-        return list(self.component_manager.task_result)
+        return self.component_manager.task_result
 
     # --------
     # Commands

src/ska_tango_base/base/component_manager.py

@@ -164,8 +164,6 @@ class BaseComponentManager:
 
         :return: ID, ResultCode, result.
         """
-        if not self.queue_manager.task_result:
-            return []
         return list(self.queue_manager.task_result)
 
     def off(self):

src/ska_tango_base/base/task_queue_manager.py

@@ -116,7 +116,7 @@ from uuid import uuid4
 from queue import Empty, Queue
 from datetime import datetime
 from threading import Event
-from typing import Any, Callable, Dict, Optional, Tuple
+from typing import Any, Callable, Dict, Optional, Tuple, Union
 
 import tango
 
@@ -442,7 +442,7 @@ class QueueManager:
         self._property_update_lock = threading.Lock()
         self._logger = logger if logger else logging.getLogger(__name__)
 
-        self._task_result: Optional[Tuple[str, str, str]] = None
+        self._task_result: Union[Tuple[str, str, str], Tuple[()]] = ()
         self._tasks_in_queue: Dict[str, str] = {}  # unique_id, task_name
         self._task_status: Dict[str, str] = {}  # unique_id, status
         self._threads = []
@@ -476,7 +476,7 @@ class QueueManager:
         return self._work_queue.full()
 
     @property
-    def task_result(self) -> Tuple[str, str, str]:
+    def task_result(self) -> Union[Tuple[str, str, str], Tuple[()]]:
         """Return the last task result.
 
         :return: Last task result

src/ska_tango_base/utils.py

@@ -564,8 +564,7 @@ class StoredCommand:
 
 
 class LongRunningDeviceInterface:
-    """This class is a convenience class to be used by clients of devices
-    that implement long running commands.
+    """This class is a convenience class for long running command devices.
 
     The intent of this class is that clients should not have to keep
     track of command IDs or the various attributes
@@ -614,7 +613,7 @@ class LongRunningDeviceInterface:
                 )
 
     def push_event(self, ev: EventData):
-        """Handles the attribute change events.
+        """Handle the attribute change events.
 
         For every event that comes in:
 

tests/conftest.py

@@ -225,6 +225,7 @@ def logger():
 
 @pytest.fixture(scope="module")
 def devices_to_test(request):
+    """Fixture for devices to test."""
     yield getattr(request.module, "devices_to_test")
 
 
@@ -233,7 +234,8 @@ def multi_device_tango_context(
     mocker, devices_to_test  # pylint: disable=redefined-outer-name
 ):
     """
-    Creates and returns a TANGO MultiDeviceTestContext object, with
+    Create and return a TANGO MultiDeviceTestContext object.
+
     tango.DeviceProxy patched to work around a name-resolving issue.
     """
 
@@ -251,9 +253,7 @@ def multi_device_tango_context(
     mocker.patch(
         "tango.DeviceProxy",
         wraps=lambda fqdn, *args, **kwargs: _DeviceProxy(
-            "tango://{0}:{1}/{2}#dbase=no".format(HOST, PORT, fqdn),
-            *args,
-            **kwargs
+            "tango://{0}:{1}/{2}#dbase=no".format(HOST, PORT, fqdn), *args, **kwargs
         ),
     )
     with MultiDeviceTestContext(

tests/long_running_tasks/reference_base_device.py

@@ -61,7 +61,9 @@ class LongRunningCommandBaseTestDevice(SKABaseDevice):
 
         self.register_command_object(
             "TestProgressWithArgs",
-            self.TestProgressWithArgsCommand(self.component_manager, logger=self.logger),
+            self.TestProgressWithArgsCommand(
+                self.component_manager, logger=self.logger
+            ),
         )
 
     class ShortCommand(ResponseCommand):
@@ -194,8 +196,7 @@ class LongRunningCommandBaseTestDevice(SKABaseDevice):
         def do(self):
             """Execute something on the long running device."""
             interface = self.target.lrc_device_interface
-            interface.execute_long_running_command(
-                "TestProgress", 0.5, None)
+            interface.execute_long_running_command("TestProgress", 0.5, None)
             self.logger.info("In TestProgressNoArgsCommand")
             return (ResultCode.OK, "Done TestProgressNoArgsCommand")
 
@@ -216,8 +217,7 @@ class LongRunningCommandBaseTestDevice(SKABaseDevice):
         def do(self, argin):
             """Execute something on the long running device."""
             interface = self.target.lrc_device_interface
-            interface.execute_long_running_command(
-                "TestProgress", argin, None)
+            interface.execute_long_running_command("TestProgress", argin, None)
             self.logger.info("In TestProgressWithArgs")
             return (ResultCode.OK, "Done TestProgressWithArgsCommand")