Merge pull request #871 from NHSDigital/11594-mammogram-workflow-states--sql-bug-fix

Fix appointment status filtering

Author: malcolmbaig

manage_breast_screening/participants/models/appointment.py

@@ -15,15 +15,16 @@
 
 class AppointmentQuerySet(models.QuerySet):
     def in_status(self, *statuses):
-        return self.filter(
-            statuses=Subquery(
-                AppointmentStatus.objects.filter(
-                    appointment=OuterRef("pk"),
-                    name__in=statuses,
-                )
-                .values("pk")
-                .order_by("-created_at")[:1]
-            )
+        # Get the most recent status name for each appointment
+        most_recent_status = (
+            AppointmentStatus.objects.filter(appointment=OuterRef("pk"))
+            .order_by("-created_at")
+            .values("name")[:1]
+        )
+
+        # Filter appointments where the most recent status name is in the provided list
+        return self.annotate(current_status_name=Subquery(most_recent_status)).filter(
+            current_status_name__in=statuses
         )
 
     def remaining(self):

manage_breast_screening/participants/tests/test_models.py

@@ -255,6 +255,50 @@ def test_for_participant(self):
             ordered=False,
         )
 
+    def test_in_status_only_matches_latest_status_not_history(
+        self, django_assert_num_queries
+    ):
+        appointment = AppointmentFactory.create()
+        appointment_with_history = AppointmentFactory.create()
+
+        AppointmentStatusFactory.create(
+            appointment=appointment,
+            name=models.AppointmentStatus.CHECKED_IN,
+            created_at=datetime(2025, 1, 1, 9, tzinfo=tz.utc),
+        )
+        AppointmentStatusFactory.create(
+            appointment=appointment_with_history,
+            name=models.AppointmentStatus.CHECKED_IN,
+            created_at=datetime(2025, 1, 2, 10, tzinfo=tz.utc),
+        )
+        AppointmentStatusFactory.create(
+            appointment=appointment_with_history,
+            name=models.AppointmentStatus.SCREENED,
+            created_at=datetime(2025, 1, 2, 11, tzinfo=tz.utc),
+        )
+
+        with django_assert_num_queries(3):
+            assertQuerySetEqual(
+                models.Appointment.objects.in_status(
+                    models.AppointmentStatus.CHECKED_IN
+                ),
+                [appointment],
+                ordered=False,
+            )
+            assertQuerySetEqual(
+                models.Appointment.objects.in_status(
+                    models.AppointmentStatus.CHECKED_IN,
+                    models.AppointmentStatus.SCREENED,
+                ),
+                [appointment, appointment_with_history],
+                ordered=False,
+            )
+            assertQuerySetEqual(
+                models.Appointment.objects.in_status(models.AppointmentStatus.SCREENED),
+                [appointment_with_history],
+                ordered=False,
+            )
+
     @pytest.mark.django_db
     class TestEagerLoadCurrentStatus:
         def test_eager_loads_most_recent_status_with_created_by(