use create_autospec

Author: rickwierenga

pylabrobot/liquid_handling/liquid_handler.py

@@ -8,6 +8,7 @@
 import json
 import logging
 import threading
+import unittest.mock
 import warnings
 from typing import (
   Any,
@@ -290,6 +291,10 @@ def _check_args(
       The set of arguments that need to be removed from `backend_kwargs` before passing to `method`.
     """
 
+    # if method is an AsyncMock, skip the checks
+    if isinstance(method, unittest.mock.AsyncMock):
+      return set()
+
     default_args = default.union({"self"})
 
     sig = inspect.signature(method)

pylabrobot/liquid_handling/liquid_handler_tests.py

@@ -650,9 +650,9 @@ async def test_return_tips96(self):
   async def test_aspirate_dispense96(self):
     await self.lh.pick_up_tips96(self.tip_rack)
     await self.lh.aspirate96(self.plate, volume=10)
-    self.lh.backend.dispense96 = unittest.mock.AsyncMock()  # type: ignore
-    await self.lh.dispense96(self.plate, volume=10)
-    self.lh.backend.dispense96.assert_called_with(
+    self.lh.backend.dispense96 = unittest.mock.create_autospec(self.lh.backend.dispense96)  # type: ignore
+    await self.lh.dispense96(self.plate, 10)
+    self.lh.backend.dispense96.assert_called_with(  # type: ignore
       dispense=MultiHeadDispensePlate(
         wells=self.plate.get_all_items(),
         offset=Coordinate.zero(),