diff --git a/tests/lib/test_structure.py b/tests/lib/test_structure.py
index de0f01ab..cbd4c3e0 100644
--- a/tests/lib/test_structure.py
+++ b/tests/lib/test_structure.py
@@ -39,12 +39,14 @@ def test_structure(data_filename, structure_filename, verbose=False):
     try:
         with open(data_filename, 'rb') as file:
             loader = yaml.Loader(file)
-        while loader.check_event():
-            if loader.check_event(yaml.StreamStartEvent, yaml.StreamEndEvent,
-                                yaml.DocumentStartEvent, yaml.DocumentEndEvent):
-                loader.get_event()
-                continue
-            nodes1.append(_convert_structure(loader))
+            while loader.check_event():
+                if loader.check_event(
+                    yaml.StreamStartEvent, yaml.StreamEndEvent,
+                    yaml.DocumentStartEvent, yaml.DocumentEndEvent
+                ):
+                    loader.get_event()
+                    continue
+                nodes1.append(_convert_structure(loader))
         if len(nodes1) == 1:
             nodes1 = nodes1[0]
         assert nodes1 == nodes2, (nodes1, nodes2)