gh-126845: Some edge cases in email.utils.parsedate_to_datetime seem to differ from RFC2822 spec

Lib/email/_parseaddr.py

@@ -149,7 +149,7 @@ def _parsedate_tz(data):
     # calls for a two-digit yy, but RFC 2822 (which obsoletes RFC 822)
     # mandates a 4-digit yy. For more information, see the documentation for
     # the time module.
-    if yy < 100:
+    if yy < 999:
         # The year is between 1969 and 1999 (inclusive).
         if yy > 68:
             yy += 1900

Lib/test/test_email/test_utils.py

@@ -186,5 +186,18 @@ def test_formatdate_with_localtime(self):
         string = utils.formatdate(timeval, localtime=True)
         self.assertEqual(string, 'Thu, 01 Dec 2011 18:00:00 +0300')
 
+# Issue #126845: Some edge cases seem to differ from RFC28222 spec
+class ParsedateToDatetimeTest(unittest.TestCase):
+    def test_year_parsing_edge_cases(self):
+        expectations = {
+            "Sat, 15 Aug 0001 23:12:09 +0500": "2001",
+            "Thu, 1 Sep 1 23:12:09 +0800": "2001",
+            "Thu, 7 Oct 123 23:12:09 +0500": "2023",
+            "Tue, 17 Nov 2026 12:12:09 +0500": "2026",
+        }
+        for input_string, output_string in expectations.items():
+            with self.subTest(input_string=input_string):
+                self.assertEqual(str(utils.parsedate_to_datetime(input_string))[:4], output_string)
+
 if __name__ == '__main__':
     unittest.main()

Misc/NEWS.d/next/Library/2025-05-21-15-32-04.gh-issue-126845.QhEGg6.rst

@@ -0,0 +1,2 @@
+Fixed _parsedate_tz to not evaluate 1 digit years as as 4-digit years, adhering to RFC 2855 4.3
+Contributed by Gustaf Gyllensporre.