fixup! Factor out the region computation

tests/test_middleware_interface.py

@@ -225,11 +225,6 @@ def test_init(self):
         self.assertEqual(self.interface.rawIngestTask.config.failFast, True)
         self.assertEqual(self.interface.rawIngestTask.config.transfer, "copy")
 
-    def test_compute_region(self):
-        """Test preload region computation."""
-        region = self.interface._compute_region()
-        self.assertTrue(isinstance(region, lsst.sphgeom.Region))
-
     def _check_imports(self, butler, group, detector, expected_shards):
         """Test that the butler has the expected supporting data.
         """
@@ -1333,3 +1328,12 @@ def test_export_outputs(self):
         self.assertEqual(
             self._count_datasets(central_butler, ["raw", "calexp"], f"{instname}/defaults"),
             0)
+
+    def test_compute_region(self):
+        """Test preload region computation."""
+        region = self.interface._compute_region()
+        self.assertTrue(isinstance(region, lsst.sphgeom.Region))
+        results = self.interface.butler.query_dimension_records("visit_detector_region", instrument=instname, group="1")
+        visit_detector_region = list(results)[0].region
+        # TODO: DM-47460 for a better test.
+        self.assertTrue(visit_detector_region.intersects(region))