From 518b2389673833887b26a8474eeb9530d17e2b8d Mon Sep 17 00:00:00 2001
From: Marek Suscak <marek.suscak@gmail.com>
Date: Mon, 16 May 2022 18:19:04 +0200
Subject: [PATCH] [3.9] bpo-34480: fix bug where match variable is used prior
 to being defined (GH-17643) (GH-32256)
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

Co-authored-by: Ezio Melotti <ezio.melotti@gmail.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
---
 Lib/_markupbase.py                            |  1 +
 Lib/test/test_htmlparser.py                   | 22 +++++++++++++++++++
 .../2022-04-09-11-28-49.bpo-34480.Pw-GJ6.rst  |  3 +++
 3 files changed, 26 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Library/2022-04-09-11-28-49.bpo-34480.Pw-GJ6.rst

diff --git a/Lib/_markupbase.py b/Lib/_markupbase.py
index 2af5f1c23b6..7091eb635b3 100644
--- a/Lib/_markupbase.py
+++ b/Lib/_markupbase.py
@@ -157,6 +157,7 @@ def parse_marked_section(self, i, report=1):
             match= _msmarkedsectionclose.search(rawdata, i+3)
         else:
             self.error('unknown status keyword %r in marked section' % rawdata[i+3:j])
+            match = None
         if not match:
             return -1
         if report:
diff --git a/Lib/test/test_htmlparser.py b/Lib/test/test_htmlparser.py
index 12917755a56..44a76a445d8 100644
--- a/Lib/test/test_htmlparser.py
+++ b/Lib/test/test_htmlparser.py
@@ -787,5 +787,27 @@ def test_weird_chars_in_unquoted_attribute_values(self):
                             ('starttag', 'form',
                                 [('action', 'bogus|&#()value')])])
 
+    def test_invalid_keyword_error_exception(self):
+        # bpo-34480: check that subclasses that define an
+        # error method that raises an exception work
+        class InvalidMarkupException(Exception):
+            pass
+        class MyHTMLParser(html.parser.HTMLParser):
+            def error(self, message):
+                raise InvalidMarkupException(message)
+        parser = MyHTMLParser()
+        with self.assertRaises(InvalidMarkupException):
+            parser.feed('<![invalid>')
+
+    def test_invalid_keyword_error_pass(self):
+        # bpo-34480: check that subclasses that define an
+        # error method that doesn't raise an exception work
+        class MyHTMLParser(html.parser.HTMLParser):
+            def error(self, message):
+                pass
+        parser = MyHTMLParser()
+        self.assertEqual(parser.feed('<![invalid>'), None)
+
+
 if __name__ == "__main__":
     unittest.main()
diff --git a/Misc/NEWS.d/next/Library/2022-04-09-11-28-49.bpo-34480.Pw-GJ6.rst b/Misc/NEWS.d/next/Library/2022-04-09-11-28-49.bpo-34480.Pw-GJ6.rst
new file mode 100644
index 00000000000..748df89b07e
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2022-04-09-11-28-49.bpo-34480.Pw-GJ6.rst
@@ -0,0 +1,3 @@
+Fix a bug where :mod:`_markupbase` raised an :exc:`UnboundLocalError`
+when an invalid keyword was found in marked section. Patch by Marek
+Suscak.