Sharpness monitor accepting 0 as None

src/openflexure_microscope_server/things/autofocus.py

@@ -274,7 +274,7 @@ class JPEGSharpnessMonitor:
             dependency as required by the underlying class.
         :param method: The sharpness metric used when evaluating autofocus.
         :param record: Bitmask of sharpness metrics to record while monitoring.
-            If ``None``, only the metric specified by ``method`` is recorded.
+            If ``None`` or 0, only the metric specified by ``method`` is recorded.
 
         :raises ValueError: If ``method`` is not included in ``record``.
         :raises ValueError: If ``SharpnessMethod.FOCUS_FOM`` is requested but
@@ -283,7 +283,7 @@ class JPEGSharpnessMonitor:
         self.camera = camera
         self.stage = stage
         self.method = method
-        self.record = method if record is None else record
+        self.record = method if record is None or record == 0 else record
 
         if not self.method & self.record:
             raise ValueError(

tests/unit_tests/test_autofocus.py

@@ -129,6 +129,17 @@ def test_record_defaults_to_method(mock_stage, mock_camera):
 
     assert monitor.record == SharpnessMethod.FOCUS_FOM
 
+def test_zero_record_defaults_to_method(mock_stage, mock_camera):
+    """If record=0, only the selected method is recorded."""
+    monitor = JPEGSharpnessMonitor(
+        mock_stage,
+        mock_camera,
+        method=SharpnessMethod.FOCUS_FOM,
+        record=0,
+    )
+
+    assert monitor.record == SharpnessMethod.FOCUS_FOM
+
 
 def test_record_must_include_selected_method(mock_stage, mock_camera):
     """The selected autofocus metric must also be recorded."""