can do this

tests/safety/common.py

@@ -439,6 +439,7 @@ class PandaSafetyTest(PandaSafetyTestBase):
   RELAY_MALFUNCTION_BUS: Optional[int] = None
   FWD_BLACKLISTED_ADDRS: Dict[int, List[int]] = {}  # {bus: [addr]}
   FWD_BUS_LOOKUP: Dict[int, int] = {}
+  HAS_REGEN_MSG: bool = False  # whether safety mode implements a user regen paddle message
 
   @classmethod
   def setUpClass(cls):
@@ -545,14 +546,6 @@ def test_alternative_experience_no_disengage_on_gas(self):
     self._rx(self._user_gas_msg(0))
     self.assertTrue(self.safety.get_longitudinal_allowed())
 
-  def test_prev_brake(self):
-    self.assertFalse(self.safety.get_brake_pressed_prev())
-    for pressed in [True, False]:
-      self._rx(self._user_brake_msg(not pressed))
-      self.assertEqual(not pressed, self.safety.get_brake_pressed_prev())
-      self._rx(self._user_brake_msg(pressed))
-      self.assertEqual(pressed, self.safety.get_brake_pressed_prev())
-
   def test_enable_control_allowed_from_cruise(self):
     self._rx(self._pcm_status_msg(False))
     self.assertFalse(self.safety.get_controls_allowed())
@@ -571,37 +564,73 @@ def test_cruise_engaged_prev(self):
       self._rx(self._pcm_status_msg(not engaged))
       self.assertEqual(not engaged, self.safety.get_cruise_engaged_prev())
 
-  def test_allow_brake_at_zero_speed(self):
+  def test_prev_brake(self, user_brake_msg=None, get_brake_pressed_prev=None):
+    if user_brake_msg is None or get_brake_pressed_prev is None:
+      user_brake_msg = self._user_brake_msg
+      get_brake_pressed_prev = self.safety.get_brake_pressed_prev
+
+    self.assertFalse(get_brake_pressed_prev())
+    for pressed in [True, False]:
+      self._rx(user_brake_msg(not pressed))
+      self.assertEqual(not pressed, get_brake_pressed_prev())
+      self._rx(user_brake_msg(pressed))
+      self.assertEqual(pressed, get_brake_pressed_prev())
+
+  def test_allow_brake_at_zero_speed(self, user_brake_msg=None):
+    if user_brake_msg is None:
+      user_brake_msg = self._user_brake_msg
+
     # Brake was already pressed
     self._rx(self._speed_msg(0))
-    self._rx(self._user_brake_msg(1))
+    self._rx(user_brake_msg(1))
     self.safety.set_controls_allowed(1)
-    self._rx(self._user_brake_msg(1))
+    self._rx(user_brake_msg(1))
     self.assertTrue(self.safety.get_controls_allowed())
     self.assertTrue(self.safety.get_longitudinal_allowed())
-    self._rx(self._user_brake_msg(0))
+    self._rx(user_brake_msg(0))
     self.assertTrue(self.safety.get_controls_allowed())
     self.assertTrue(self.safety.get_longitudinal_allowed())
     # rising edge of brake should disengage
-    self._rx(self._user_brake_msg(1))
+    self._rx(user_brake_msg(1))
     self.assertFalse(self.safety.get_controls_allowed())
     self.assertFalse(self.safety.get_longitudinal_allowed())
-    self._rx(self._user_brake_msg(0))  # reset no brakes
+    self._rx(user_brake_msg(0))  # reset no brakes
+
+  def test_not_allow_brake_when_moving(self, user_brake_msg=None):
+    if user_brake_msg is None:
+      user_brake_msg = self._user_brake_msg
 
-  def test_not_allow_brake_when_moving(self):
     # Brake was already pressed
-    self._rx(self._user_brake_msg(1))
+    self._rx(user_brake_msg(1))
     self.safety.set_controls_allowed(1)
     self._rx(self._speed_msg(self.STANDSTILL_THRESHOLD))
-    self._rx(self._user_brake_msg(1))
+    self._rx(user_brake_msg(1))
     self.assertTrue(self.safety.get_controls_allowed())
     self.assertTrue(self.safety.get_longitudinal_allowed())
     self._rx(self._speed_msg(self.STANDSTILL_THRESHOLD + 1))
-    self._rx(self._user_brake_msg(1))
+    self._rx(user_brake_msg(1))
     self.assertFalse(self.safety.get_controls_allowed())
     self.assertFalse(self.safety.get_longitudinal_allowed())
     self._rx(self._speed_msg(0))
 
+  def test_prev_regen(self):
+    if not self.HAS_REGEN_MSG:
+      raise unittest.SkipTest("Safety mode does not implement a user regen message")
+
+    self.test_prev_brake(self._user_regen_msg, self.safety.get_regen_braking_prev)
+
+  def test_allow_regen_at_zero_speed(self):
+    if not self.HAS_REGEN_MSG:
+      raise unittest.SkipTest("Safety mode does not implement a user regen message")
+
+    self.test_allow_brake_at_zero_speed(self._user_regen_msg)
+
+  def test_not_allow_regen_when_moving(self):
+    if not self.HAS_REGEN_MSG:
+      raise unittest.SkipTest("Safety mode does not implement a user regen message")
+
+    self.test_not_allow_brake_when_moving(self._user_regen_msg)
+
   def test_sample_speed(self):
     self.assertFalse(self.safety.get_vehicle_moving())
 
@@ -658,28 +687,3 @@ def test_tx_hook_on_wrong_safety_mode(self):
         if current_test in ["TestNissanSafety", "TestNissanLeafSafety"] and [addr, bus] in self.TX_MSGS:
           continue
         self.assertFalse(self._tx(msg), f"transmit of {addr=:#x} {bus=} from {test_name} was allowed")
-
-
-class RegenSafetyTest(PandaSafetyTestBase):
-  # pylint: disable=no-member
-
-  @classmethod
-  def setUpClass(cls):
-    if cls.__name__ == "RegenSafetyTest":
-      cls.safety = None
-      raise unittest.SkipTest
-
-  def test_prev_regen_brake(self):
-    self._user_brake_msg = self._user_regen_msg
-    get_brake_pressed_prev = self.safety.get_brake_pressed_prev
-    self.safety.__dict__['get_brake_pressed_prev'] = self.safety.get_regen_braking_prev
-    super().test_prev_brake()
-    self.safety.__dict__['get_brake_pressed_prev'] = get_brake_pressed_prev
-
-  def test_allow_regen_brake_at_zero_speed(self):
-    self._user_brake_msg = self._user_regen_msg
-    super().test_allow_brake_at_zero_speed()
-
-  def test_not_allow_regen_brake_when_moving(self):
-    self._user_brake_msg = self._user_regen_msg
-    super().test_not_allow_brake_when_moving()

tests/safety/test_gm.py

@@ -18,7 +18,7 @@ class Buttons:
   CANCEL = 6
 
 
-class TestGmSafetyBase(common.RegenSafetyTest, common.PandaSafetyTest, common.DriverTorqueSteeringSafetyTest):
+class TestGmSafetyBase(common.PandaSafetyTest, common.DriverTorqueSteeringSafetyTest):
   STANDSTILL_THRESHOLD = 0
   RELAY_MALFUNCTION_ADDR = 384
   RELAY_MALFUNCTION_BUS = 0
@@ -32,6 +32,8 @@ class TestGmSafetyBase(common.RegenSafetyTest, common.PandaSafetyTest, common.Dr
   DRIVER_TORQUE_ALLOWANCE = 50
   DRIVER_TORQUE_FACTOR = 4
 
+  HAS_REGEN_MSG = True
+
   @classmethod
   def setUpClass(cls):
     if cls.__name__ == "TestGmSafetyBase":