Compatibility: pycode parser: adjust dedent-token handling for py3.12+

Refs: #11436

Author: jayaddison

sphinx/pycode/parser.py

@@ -6,6 +6,7 @@
 import inspect
 import itertools
 import re
+import sys
 import tokenize
 from inspect import Signature
 from token import DEDENT, INDENT, NAME, NEWLINE, NUMBER, OP, STRING
@@ -525,7 +526,16 @@ def finalize_block(self) -> None:
         definition = self.indents.pop()
         if definition[0] != 'other':
             typ, funcname, start_pos = definition
-            end_pos = self.current.end[0] - 1
+            end_pos = self.current.end[0]
+
+            # The dedent end position on py3.12 is capped to the file linecount
+            # refs: https://github.com/sphinx-doc/sphinx/issues/11436
+            if sys.version_info[:2] >= (3, 12) and end_pos == len(self.buffers):
+                pass
+            else:
+                end_pos -= 1
+
+            # Omit empty dedenting lines from the definition's location
             while emptyline_re.match(self.get_line(end_pos)):
                 end_pos -= 1