Assert on the storage under test, not on process-global mock state, in test_metric_reader_storage.py

.changelog/5639.fixed

@@ -0,0 +1 @@
+`opentelemetry-sdk`: make the `MetricReaderStorage` tests assert on the storage under test instead of on process-global mock state, so an unrelated `_ViewInstrumentMatch` construction elsewhere in the test session can no longer fail them

opentelemetry-sdk/tests/metrics/test_metric_reader_storage.py

@@ -73,32 +73,28 @@ def test_creates_view_instrument_matches(self, MockViewInstrumentMatch: Mock):
         # instrument1 matches view1 and view2, so should create two
         # ViewInstrumentMatch objects
         storage.consume_measurement(Measurement(1, time_ns(), instrument1, Context()))
-        self.assertEqual(
-            len(MockViewInstrumentMatch.call_args_list),
-            2,
-            MockViewInstrumentMatch.mock_calls,
-        )
+        matches = storage._instrument_view_instrument_matches[instrument1]
+        self.assertEqual(len(matches), 2, matches)
+
         # they should only be created the first time the instrument is seen
         storage.consume_measurement(Measurement(1, time_ns(), instrument1, Context()))
-        self.assertEqual(len(MockViewInstrumentMatch.call_args_list), 2)
+        self.assertIs(storage._instrument_view_instrument_matches[instrument1], matches)
+        self.assertEqual(len(matches), 2, matches)
 
         # instrument2 matches view2, so should create a single
         # ViewInstrumentMatch
-        MockViewInstrumentMatch.call_args_list.clear()
         with self.assertLogs(level=WARNING):
             storage.consume_measurement(Measurement(1, time_ns(), instrument2, Context()))
-        self.assertEqual(len(MockViewInstrumentMatch.call_args_list), 1)
+        self.assertEqual(len(storage._instrument_view_instrument_matches[instrument2]), 1)
 
     @patch("opentelemetry.sdk.metrics._internal.metric_reader_storage._ViewInstrumentMatch")
     def test_forwards_calls_to_view_instrument_match(self, MockViewInstrumentMatch: Mock):
-        view_instrument_match1 = Mock(_aggregation=_LastValueAggregation({}, Mock(), instrument_is_synchronous=True))
-        view_instrument_match2 = Mock(_aggregation=_LastValueAggregation({}, Mock(), instrument_is_synchronous=True))
-        view_instrument_match3 = Mock(_aggregation=_LastValueAggregation({}, Mock(), instrument_is_synchronous=True))
-        MockViewInstrumentMatch.side_effect = [
-            view_instrument_match1,
-            view_instrument_match2,
-            view_instrument_match3,
-        ]
+        # Build a fresh mock per call rather than handing out a fixed list, so
+        # that a construction from elsewhere in the process cannot consume an
+        # entry this test is relying on.
+        MockViewInstrumentMatch.side_effect = lambda *args, **kwargs: Mock(
+            _aggregation=_LastValueAggregation({}, Mock(), instrument_is_synchronous=True)
+        )
 
         instrument1 = Mock(name="instrument1")
         instrument2 = Mock(name="instrument2")
@@ -119,13 +115,18 @@ def test_forwards_calls_to_view_instrument_match(self, MockViewInstrumentMatch:
         # ViewInstrumentMatch objects created for that instrument
         measurement = Measurement(1, time_ns(), instrument1, Context())
         storage.consume_measurement(measurement)
+        (
+            view_instrument_match1,
+            view_instrument_match2,
+        ) = storage._instrument_view_instrument_matches[instrument1]
         view_instrument_match1.consume_measurement.assert_called_once_with(measurement, True)
         view_instrument_match2.consume_measurement.assert_called_once_with(measurement, True)
-        view_instrument_match3.consume_measurement.assert_not_called()
+        self.assertNotIn(instrument2, storage._instrument_view_instrument_matches)
 
         measurement = Measurement(1, time_ns(), instrument2, Context())
         with self.assertLogs(level=WARNING):
             storage.consume_measurement(measurement)
+        (view_instrument_match3,) = storage._instrument_view_instrument_matches[instrument2]
         view_instrument_match3.consume_measurement.assert_called_once_with(measurement, True)
 
         # collect() should call collect on all of its _ViewInstrumentMatch
@@ -238,17 +239,15 @@ def test_default_view_enabled(self, MockViewInstrumentMatch: Mock):
         )
 
         storage.consume_measurement(Measurement(1, time_ns(), instrument1, Context()))
-        self.assertEqual(
-            len(MockViewInstrumentMatch.call_args_list),
-            1,
-            MockViewInstrumentMatch.mock_calls,
-        )
+        matches = storage._instrument_view_instrument_matches[instrument1]
+        self.assertEqual(len(matches), 1, matches)
+
         storage.consume_measurement(Measurement(1, time_ns(), instrument1, Context()))
-        self.assertEqual(len(MockViewInstrumentMatch.call_args_list), 1)
+        self.assertIs(storage._instrument_view_instrument_matches[instrument1], matches)
+        self.assertEqual(len(matches), 1, matches)
 
-        MockViewInstrumentMatch.call_args_list.clear()
         storage.consume_measurement(Measurement(1, time_ns(), instrument2, Context()))
-        self.assertEqual(len(MockViewInstrumentMatch.call_args_list), 1)
+        self.assertEqual(len(storage._instrument_view_instrument_matches[instrument2]), 1)
 
     def test_drop_aggregation(self):
         counter = _Counter("name", Mock(), Mock())