[parsing] unify tag nesting

test/test_parsing.py

@@ -325,9 +325,9 @@ class TestParsing(unittest.TestCase):
             str(tags), str([
                 [Tag('t0'),
                  [Tag('t1'),
-                  [Tag('t2'), Tag('t3'), Tag('t4')]],
+                  [Tag('t2'), [Tag('t3')], [Tag('t4')]]],
-                 [Tag('t5'), Tag('t6')]],
+                 [Tag('t5'), [Tag('t6')]]],
-                [Tag('t7'), Tag('t8')]]))
+                [Tag('t7'), [Tag('t8')]]]))
 
     def test_html_ignored_ranges(self):
         def mark_comments(_string, char='^', nochar='-'):

yt_dlp/parsing.py

@@ -174,12 +174,11 @@ class HTMLTagParser(HTMLParser):
         if self.predicate(tag, attrs):
             tag_obj = self.Tag(tag, string=self.rawdata, attrs=attrs)
             tag_obj.openrange(self._offset, len(tag_text))
+            nesting = [tag_obj]
+            self._nestedtags[-1].append(nesting)
             if tag_is_open:
-                nesting = [tag_obj]
-                self._nestedtags[-1].append(nesting)
                 self._nestedtags.append(nesting)
             else:
-                self._nestedtags[-1].append(tag_obj)
                 self.callback(tag_obj)
         if tag_is_open:
             self.tagstack.appendleft(tag_obj)