ci: Add unit test to prevent MADS DM regressions (#1602)

* monitoring/tests: Add unit test to prevent MADS regressions

* dm: remove TODO

---------

Co-authored-by: Jason Wen <haibin.wen3@gmail.com>

selfdrive/monitoring/helpers.py

@@ -449,7 +449,6 @@ class DriverMonitoring:
       rpyCalib = [0., 0., 0.]
     else:
       highway_speed = sm['carState'].vEgo
-      # TODO-SP: unit test to assert both control checks are always present
       enabled = sm['selfdriveState'].enabled or sm['carControl'].latActive
       wrong_gear = sm['carState'].gearShifter not in (car.CarState.GearShifter.drive, car.CarState.GearShifter.low)
       standstill = sm['carState'].standstill

selfdrive/monitoring/test_monitoring.py

@@ -1,6 +1,7 @@
 import numpy as np
+import pytest
 
-from cereal import log
+from cereal import log, car
 from openpilot.common.realtime import DT_DMON
 from openpilot.selfdrive.monitoring.helpers import DriverMonitoring, DRIVER_MONITOR_SETTINGS
 from openpilot.system.hardware import HARDWARE
@@ -204,3 +205,66 @@ class TestMonitoring:
     assert EventName.driverUnresponsive in \
                               events[int((INVISIBLE_SECONDS_TO_RED-1+DT_DMON*d_status.settings._HI_STD_FALLBACK_TIME+0.1)/DT_DMON)].names
 
+
+@pytest.mark.parametrize("enabled_state, lat_active_state, expected", [
+  (False, False, False), # Both Disabled
+  (True, False, True),   # OP Enabled, Lat Inactive
+  (False, True, True),   # OP Disabled, Lat Active (e.g. MADS)
+  (True, True, True)     # Both Active
+])
+def test_enabled_states(enabled_state, lat_active_state, expected):
+  """
+  Test DriverMonitoring.run_step with all 4 combinations of:
+  - selfdriveState.enabled (True/False)
+  - carControl.latActive (True/False)
+  """
+  cs = car.CarState.new_message()
+  cs.vEgo = 30.0
+  cs.gearShifter = car.CarState.GearShifter.drive
+  cs.standstill = False
+  cs.steeringPressed = False
+  cs.gasPressed = False
+
+  ss = log.SelfdriveState.new_message()
+  ss.enabled = enabled_state
+
+  cc = car.CarControl.new_message()
+  cc.latActive = lat_active_state
+
+  mv2 = log.ModelDataV2.new_message()
+  mv2.meta.disengagePredictions.brakeDisengageProbs = [0.0]
+
+  lc = log.LiveCalibrationData.new_message()
+  lc.rpyCalib = [0.0, 0.0, 0.0]
+
+  ds = make_msg(False)
+
+  sm = {
+      'carState': cs,
+      'selfdriveState': ss,
+      'carControl': cc,
+      'modelV2': mv2,
+      'liveCalibration': lc,
+      'driverStateV2': ds
+  }
+
+  driver_monitoring = DriverMonitoring()
+
+  # run_test doesn't assign enabled to a variable, so we need to spy on _update_events to see its value
+  captured_args = []
+  original_update_events = driver_monitoring._update_events
+
+  def spy_update_events(driver_engaged, op_engaged, standstill, wrong_gear, car_speed):
+      captured_args.append(op_engaged)
+      return original_update_events(driver_engaged, op_engaged, standstill, wrong_gear, car_speed)
+
+  driver_monitoring._update_events = spy_update_events
+
+  driver_monitoring.run_step(sm, demo=False)
+
+  # Assertion
+  assert len(captured_args) == 1, "Expected _update_events to be called exactly once"
+  actual_enabled = captured_args[0]
+
+  assert actual_enabled == expected, f"Expected op_engaged={expected}, but got {actual_enabled}"
+