Add a test for multi querysets

Author: AlanCoding

ansible_base/resource_registry/fields.py

@@ -15,10 +15,7 @@ def get_queryset(self, **hints):
 
     def get_prefetch_querysets(self, instances, querysets=None):
         if querysets and len(querysets) != 1:
-            raise ValueError(
-                "querysets argument of get_prefetch_querysets() should have a length "
-                "of 1."
-            )
+            raise ValueError("querysets argument of get_prefetch_querysets() should have a length " "of 1.")
         queryset = querysets[0] if querysets else self.get_queryset()
         queryset._add_hints(instance=instances[0])
 

test_app/tests/resource_registry/models/test_resource_field.py

@@ -2,7 +2,7 @@
 from django.contrib.contenttypes.models import ContentType
 
 from ansible_base.resource_registry.models import Resource
-from test_app.models import Organization
+from test_app.models import Inventory, Organization
 
 
 @pytest.mark.django_db
@@ -100,3 +100,48 @@ def test_resource_field_filtering(organization):
 
     org = Organization.objects.get(resource__name=organization.name)
     assert org.resource.pk == resource.pk
+
+
+@pytest.mark.django_db
+def test_resource_field_prefetch_related_across_foreign_key(organization, organization_1, organization_2, django_assert_num_queries):
+    """
+    Generated by Claude Code (claude-sonnet-4-5@20250929)
+    Test that prefetch_related works across a ForeignKey to a model with a resource field.
+    This tests prefetching organization__resource on Inventory objects.
+    """
+    # Create inventory objects linked to organizations
+    Inventory.objects.create(name="Inventory 1", organization=organization)
+    Inventory.objects.create(name="Inventory 2", organization=organization_1)
+    Inventory.objects.create(name="Inventory 3", organization=organization_2)
+
+    org_ctype = ContentType.objects.get_for_model(Organization)
+
+    # Prefetch organization__resource should result in 3 queries:
+    # 1. Fetch all Inventory objects
+    # 2. Fetch all related Organization objects
+    # 3. Fetch all related Resource objects
+    with django_assert_num_queries(3) as captured:
+        inventory_qs = list(Inventory.objects.prefetch_related("organization__resource").all())
+
+    # Verify the queries were as expected
+    assert "test_app_inventory" in captured[0]["sql"]
+    assert "test_app_organization" in captured[1]["sql"]
+    assert "dab_resource_registry_resource" in captured[2]["sql"]
+
+    assert len(inventory_qs) == 3
+
+    # Collect resource pks for later verification
+    resource_pks = {}
+    with django_assert_num_queries(0):
+        for inv in inventory_qs:
+            assert inv.organization is not None
+            assert inv.organization.resource is not None
+            # Verify the resource data is correct
+            assert inv.organization.name == inv.organization.resource.name
+            assert str(inv.organization.pk) == inv.organization.resource.object_id
+            resource_pks[inv.organization.pk] = inv.organization.resource.pk
+
+    # Verify the resources match what's in the database
+    for org_pk, resource_pk in resource_pks.items():
+        expected_resource = Resource.objects.get(object_id=org_pk, content_type=org_ctype)
+        assert resource_pk == expected_resource.pk