Fix linting and type errors for CI

- Use X | None syntax instead of Optional[X] (UP045)
- Sort imports in dashboard app (I001)
- Remove unnecessary UTF-8 encoding argument (UP012)
- Add 'from err' to exception re-raises (B904)
- Remove unused imports in integration tests (F401)
- Fix useless expression in test (B018)
- Cast **1.5 result to float in LDO model (mypy no-any-return)
- Use functools.partial instead of lambda in server (mypy misc)

src/py_dvt_ate/app/cli.py

@@ -1,6 +1,6 @@
 """Command-line interface for py_dvt_ate."""
 
-from typing import Annotated, Optional
+from typing import Annotated
 
 import typer
 
@@ -23,7 +23,7 @@ def version_callback(value: bool) -> None:
 @app.callback()
 def main(
     version: Annotated[
-        Optional[bool],
+        bool | None,
         typer.Option(
             "--version",
             "-v",

src/py_dvt_ate/app/dashboard/app.py

@@ -12,7 +12,6 @@ import streamlit as st
 
 from py_dvt_ate.simulation.physics.engine import PhysicsEngine
 
-
 # History buffer size for charts
 HISTORY_SIZE = 500
 

src/py_dvt_ate/instruments/transport/server.py

@@ -12,6 +12,7 @@ from __future__ import annotations
 
 import asyncio
 import logging
+from functools import partial
 from typing import Protocol, runtime_checkable
 
 __all__ = ["InstrumentServer", "SCPIDevice"]
@@ -132,8 +133,9 @@ class InstrumentServer:
         self._running = True
 
         for port, instrument in self._instruments.items():
+            handler = partial(self._handle_client, instrument=instrument, port=port)
             server = await asyncio.start_server(
-                lambda r, w, inst=instrument, p=port: self._handle_client(r, w, inst, p),
+                handler,
                 self._host,
                 port,
             )
@@ -216,7 +218,7 @@ class InstrumentServer:
 
                 # Send response with newline terminator
                 if response:
-                    writer.write(f"{response}\n".encode("utf-8"))
+                    writer.write(f"{response}\n".encode())
                     await writer.drain()
                     logger.debug("Port %d sent: %s", port, response)
 

src/py_dvt_ate/simulation/physics/models/ldo.py

@@ -194,7 +194,7 @@ class LDOModel:
         # Temperature ratio (reference is approximately 300K ≈ 27°C)
         temp_ratio = t_kelvin / 300.0
 
-        return self._params.dropout_voltage * (temp_ratio**1.5)
+        return float(self._params.dropout_voltage * (temp_ratio**1.5))
 
     def is_in_dropout(self, junction_temperature: float) -> bool:
         """Check if the LDO is in dropout at current operating point.

src/py_dvt_ate/simulation/virtual/chamber.py

@@ -82,8 +82,8 @@ class ThermalChamberSim(BaseInstrument):
 
         try:
             setpoint = float(command.arguments[0])
-        except ValueError:
-            raise ValueError(f"Invalid temperature value: {command.arguments[0]}")
+        except ValueError as err:
+            raise ValueError(f"Invalid temperature value: {command.arguments[0]}") from err
 
         self._setpoint = setpoint
         if self._physics_engine is not None:

src/py_dvt_ate/simulation/virtual/power_supply.py

@@ -94,8 +94,8 @@ class PowerSupplySim(BaseInstrument):
 
         try:
             voltage = float(command.arguments[0])
-        except ValueError:
-            raise ValueError(f"Invalid voltage value: {command.arguments[0]}")
+        except ValueError as err:
+            raise ValueError(f"Invalid voltage value: {command.arguments[0]}") from err
 
         if voltage < 0:
             raise ValueError("Voltage cannot be negative")
@@ -127,8 +127,8 @@ class PowerSupplySim(BaseInstrument):
 
         try:
             current = float(command.arguments[0])
-        except ValueError:
-            raise ValueError(f"Invalid current value: {command.arguments[0]}")
+        except ValueError as err:
+            raise ValueError(f"Invalid current value: {command.arguments[0]}") from err
 
         if current < 0:
             raise ValueError("Current limit cannot be negative")

tests/integration/test_tcp_server.py

@@ -13,8 +13,6 @@ from py_dvt_ate.instruments.transport import InstrumentServer
 from py_dvt_ate.simulation.physics.engine import PhysicsEngine
 from py_dvt_ate.simulation.server import ServerConfig, SimulationServer
 from py_dvt_ate.simulation.virtual.chamber import ThermalChamberSim
-from py_dvt_ate.simulation.virtual.multimeter import MultimeterSim
-from py_dvt_ate.simulation.virtual.power_supply import PowerSupplySim
 
 
 @pytest.mark.asyncio(loop_scope="function")

tests/unit/test_physics_models.py

@@ -63,7 +63,7 @@ class TestThermalState:
 
         # Should not raise
         hash(state)
-        {state}  # Can be added to a set
+        _ = {state}  # Can be added to a set
 
 
 class TestElectricalState: