path_to_location now returns 404 on orphaned items. Resolves LMS-9661.

common/lib/xmodule/xmodule/modulestore/search.py

@@ -60,14 +60,14 @@ def path_to_location(modulestore, usage_key):
                 # Found it!
                 path = (next_usage, path)
                 return flatten(path)
+            elif parent is None:
+                # Orphaned item.
+                return None
 
             # otherwise, add parent locations at the end
             newpath = (next_usage, path)
             queue.append((parent, newpath))
 
-        # If we're here, there is no path
-        return None
-
     if not modulestore.has_item(usage_key):
         raise ItemNotFoundError(usage_key)
 

common/lib/xmodule/xmodule/modulestore/tests/test_mixed_modulestore.py

@@ -22,7 +22,8 @@ from opaque_keys.edx.locator import BlockUsageLocator, CourseLocator
 from django.conf import settings
 from xmodule.modulestore.tests.factories import check_mongo_calls
 from xmodule.modulestore.search import path_to_location
-from xmodule.modulestore.exceptions import DuplicateCourseError
+from xmodule.modulestore.exceptions import DuplicateCourseError, NoPathToItem
+
 if not settings.configured:
     settings.configure()
 from xmodule.modulestore.mixed import MixedModuleStore
@@ -723,6 +724,18 @@ class TestMixedModuleStore(unittest.TestCase):
             with self.assertRaises(ItemNotFoundError):
                 path_to_location(self.store, location)
 
+        # Orphaned items should not be found.
+        orphan = course_key.make_usage_key('chapter', 'OrphanChapter')
+        self.store.create_item(
+            self.user_id,
+            orphan.course_key,
+            orphan.block_type,
+            block_id=orphan.block_id
+        )
+
+        with self.assertRaises(NoPathToItem):
+            path_to_location(self.store, orphan)
+
     def test_xml_path_to_location(self):
         """
         Make sure that path_to_location works: should be passed a modulestore