Pretty-print expected and actual paths on assertion failures

arkindex/documents/tests/test_edit_elementpath.py

@@ -34,12 +34,22 @@ class TestEditElementPath(FixtureTestCase):
             self.assertNotIn(elements[element_name].id, tree)
             return
 
+        element_names = {e.id: e.name for e in elements.values()}
+
+        expected_paths = [
+            [elements[parent_name].id for parent_name in path]
+            for path in paths
+        ]
+        actual_paths = tree.get(elements[element_name].id, [])
+        readable_actual_paths = [
+            [element_names[id] for id in path]
+            for path in actual_paths
+        ]
+
         return self.assertCountEqual(
-            tree.get(elements[element_name].id, []),
-            [
-                [elements[parent_name].id for parent_name in path]
-                for path in paths
-            ]
+            actual_paths,
+            expected_paths,
+            f'Expected paths {paths} in element {element_name}, got {readable_actual_paths}'
         )
 
     def test_add_parent(self):