Change return type of root_instrument to Instrument

src/qcodes/instrument/channel.py

@@ -26,6 +26,7 @@
 
     from typing_extensions import Unpack
 
+    from .instrument import Instrument
     from .instrument_base import InstrumentBaseKWArgs
 
 
@@ -86,8 +87,14 @@ def parent(self) -> _TIB_co:
         return self._parent
 
     @property
-    def root_instrument(self) -> InstrumentBase:
-        return self._parent.root_instrument
+    def root_instrument(self) -> Instrument:  # type: ignore[override]
+        # the root instrument is the top level parent of this module, we need to
+        # go up the parent hierarchy until we find an object that returns itself as the parent, this should be the root instrument. We also
+        # this is required to be an Instrument.
+        # Once 3.13 is the minimum supported version
+        # consider replacing with a generic parameter with a default
+        # value of Instrument.
+        return cast("Instrument", self._parent.root_instrument)
 
     @property
     def name_parts(self) -> list[str]:

src/qcodes/instrument/instrument_base.py

@@ -18,7 +18,7 @@
 
 if TYPE_CHECKING:
     from collections.abc import Callable, Mapping, Sequence
-    from typing import NotRequired
+    from typing import NotRequired, Self
 
     from qcodes.instrument.channel import ChannelTuple, InstrumentModule
     from qcodes.logger.instrument_logger import InstrumentLoggerAdapter
@@ -579,7 +579,7 @@ def ancestors(self) -> tuple[InstrumentBase, ...]:
             return (self,)
 
     @property
-    def root_instrument(self) -> InstrumentBase:
+    def root_instrument(self) -> Self:
         """
         The topmost parent of this module.
 

src/qcodes/instrument_drivers/Keysight/Infiniium.py

@@ -526,7 +526,10 @@ def __init__(
         )
 
     @property
-    def root_instrument(self) -> "KeysightInfiniium":
+    def root_instrument(self) -> "KeysightInfiniium":  # type: ignore[override]
+        # ideally this should be a generic type parameter but
+        # for now we override it here. This requies a mypy ignore
+        # because the return type is more specific than the parent class.
         root_instrument = super().root_instrument
         assert isinstance(root_instrument, KeysightInfiniium)
         return root_instrument

src/qcodes/instrument_drivers/Keysight/KtMAwg.py

@@ -142,7 +142,10 @@ def __init__(
         """Parameter digital_gain"""
 
     @property
-    def root_instrument(self) -> "KeysightM9336A":
+    def root_instrument(self) -> "KeysightM9336A":  # type: ignore[override]
+        # ideally this should be a generic type parameter but
+        # for now we override it here. This requies a mypy ignore
+        # because the return type is more specific than the parent class.
         root_instrument = super().root_instrument
         assert isinstance(root_instrument, KeysightM9336A)
         return root_instrument

src/qcodes/instrument_drivers/Keysight/N52xx.py

@@ -300,7 +300,10 @@ def __init__(
         """Parameter polar"""
 
     @property
-    def root_instrument(self) -> "KeysightPNABase":
+    def root_instrument(self) -> "KeysightPNABase":  # type: ignore[override]
+        # ideally this should be a generic type parameter but
+        # for now we override it here. This requies a mypy ignore
+        # because the return type is more specific than the parent class.
         root_instrument = super().root_instrument
         assert isinstance(root_instrument, KeysightPNABase)
         return root_instrument

src/qcodes/instrument_drivers/tektronix/DPO7200xx.py

@@ -355,7 +355,10 @@ def __init__(
         """Parameter trace"""
 
     @property
-    def root_instrument(self) -> "TektronixDPO7000xx":
+    def root_instrument(self) -> "TektronixDPO7000xx":  # type: ignore[override]
+        # ideally this should be a generic type parameter but
+        # for now we override it here. This requies a mypy ignore
+        # because the return type is more specific than the parent class.
         root_instrument = super().root_instrument
         assert isinstance(root_instrument, TektronixDPO7000xx)
         return root_instrument

src/qcodes/monitor/monitor.py

@@ -46,6 +46,8 @@
 
     from websockets.asyncio.server import ServerConnection
 
+    from qcodes.instrument import InstrumentBase
+
 WEBSOCKET_PORT = 5678
 SERVER_PORT = 3000
 
@@ -78,7 +80,7 @@ def _get_metadata(
 
         # find the base instrument that this parameter belongs to
         if use_root_instrument:
-            baseinst = parameter.root_instrument
+            baseinst: InstrumentBase | None = parameter.root_instrument
         else:
             baseinst = parameter.instrument
         if baseinst is None:

src/qcodes/parameters/parameter_base.py

@@ -8,7 +8,7 @@
 from contextlib import contextmanager
 from datetime import datetime
 from functools import cached_property, wraps
-from typing import TYPE_CHECKING, Any, ClassVar, Generic, overload
+from typing import TYPE_CHECKING, Any, ClassVar, Generic, cast, overload
 
 import numpy as np
 from typing_extensions import TypeVar
@@ -46,7 +46,7 @@
     from types import TracebackType
 
     from qcodes.dataset.data_set_protocol import ValuesType
-    from qcodes.instrument import InstrumentBase
+    from qcodes.instrument import Instrument, InstrumentBase
     from qcodes.logger.instrument_logger import InstrumentLoggerAdapter
 ParameterDataTypeVar = TypeVar("ParameterDataTypeVar", default=Any)
 # InstrumentTypeVar_co is a covariant type variable representing the instrument
@@ -1080,15 +1080,15 @@ def instrument(self) -> InstrumentTypeVar_co:
         return self._instrument
 
     @property
-    def root_instrument(self) -> InstrumentBase | None:
+    def root_instrument(self) -> Instrument | None:
         """
         Return the fundamental instrument that this parameter belongs too.
         E.g if the parameter is bound to a channel this will return the
         fundamental instrument that that channel belongs to. Use
         :meth:`instrument` to get the channel.
         """
         if self._instrument is not None:
-            return self._instrument.root_instrument
+            return cast("Instrument | None", self._instrument.root_instrument)
         else:
             return None
 

tests/drivers/keysight_b1500/b1500_driver_tests/test_b1517a_smu.py

@@ -433,7 +433,7 @@ def test_iv_sweep_delay(smu: KeysightB1517A) -> None:
     smu.iv_sweep.step_delay(0.01)
     smu.iv_sweep.trigger_delay(0.1)
     smu.iv_sweep.measure_delay(15.4)
-
+    assert isinstance(mainframe, MagicMock)
     mainframe.write.assert_has_calls(
         [
             call("WT 43.12,0.0,0.0,0.0,0.0"),

tests/drivers/keysight_b1500/b1500_driver_tests/test_b1520a_cmu.py

@@ -179,7 +179,7 @@ def test_get_post_sweep_voltage_cond(cmu: KeysightB1520A) -> None:
 
 def test_cv_sweep_delay(cmu: KeysightB1520A) -> None:
     mainframe = cmu.root_instrument
-
+    assert isinstance(mainframe, MagicMock)
     mainframe.ask.return_value = "WTDCV0.0,0.0,0.0,0.0,0.0"
 
     cmu.cv_sweep.hold_time(1.0)
@@ -192,6 +192,7 @@ def test_cv_sweep_delay(cmu: KeysightB1520A) -> None:
 
 def test_cmu_sweep_steps(cmu: KeysightB1520A) -> None:
     mainframe = cmu.root_instrument
+    assert isinstance(mainframe, MagicMock)
     mainframe.ask.return_value = "WDCV3,1,0.0,0.0,1"
     cmu.cv_sweep.sweep_start(2.0)
     cmu.cv_sweep.sweep_end(4.0)
@@ -208,6 +209,7 @@ def test_cv_sweep_voltages(cmu: KeysightB1520A) -> None:
     end = 1.0
     steps = 5
     return_string = f"WDCV3,1,{start},{end},{steps}"
+    assert isinstance(mainframe, MagicMock)
     mainframe.ask.return_value = return_string
 
     cmu.cv_sweep.sweep_start(start)
@@ -226,6 +228,7 @@ def test_sweep_modes(cmu: KeysightB1520A) -> None:
     steps = 5
     mode = constants.SweepMode.LINEAR_TWO_WAY
     return_string = f"WDCV3,{mode},{start},{end},{steps}"
+    assert isinstance(mainframe, MagicMock)
     mainframe.ask.return_value = return_string
 
     cmu.cv_sweep.sweep_start(start)
@@ -249,6 +252,7 @@ def test_run_sweep(cmu: KeysightB1520A) -> None:
         f"0.0000;WDCV3,"
         f"1,{start},{end},{steps};ACT0,1"
     )
+    assert isinstance(mainframe, MagicMock)
     mainframe.ask.return_value = return_string
     cmu.setup_fnc_already_run = True
     cmu.impedance_model(constants.IMP.MeasurementMode.G_X)

tests/drivers/keysight_b1500/b1500_driver_tests/test_sampling_measurement.py

@@ -83,6 +83,7 @@ def test_sampling_measurement(
     actual_data = smu.sampling_measurement_trace.get()
 
     np.testing.assert_allclose(actual_data, data_to_return, atol=1e-3)
+    assert isinstance(smu.root_instrument.ask, Mock)
     smu.root_instrument.ask.assert_called_with("XE")