gh-40889: Fix email.utils.parseaddr to handle routes with multiple intermediate hops

Author: crazymerlyn

Lib/email/_parseaddr.py

@@ -349,6 +349,8 @@ def getrouteaddr(self):
             elif self.field[self.pos] == '@':
                 self.pos += 1
                 expectroute = True
+            elif self.field[self.pos] == ',':
+                self.pos += 1
             elif self.field[self.pos] == ':':
                 self.pos += 1
             else:

Lib/test/test_email/test_email.py

@@ -3289,6 +3289,12 @@ def test_parseaddr_preserves_spaces_in_local_part(self):
         self.assertEqual(('', '[email protected]'),
             utils.parseaddr('merwok. wok .  [email protected]'))
 
+    def test_parseaddr_handles_obsolete_addressing(self):
+        self.assertEqual(('foobar', '[email protected]'),
+            utils.parseaddr('"foobar" <@hop.org:[email protected]>'))
+        self.assertEqual(('foobar', '[email protected]'),
+            utils.parseaddr('"foobar" <@hop1.org,@hop2.org:[email protected]>'))
+
     def test_formataddr_does_not_quote_parens_in_quoted_string(self):
         addr = ("'[email protected]' ([email protected])",
                 '[email protected]')

Misc/NEWS.d/next/Library/2024-08-25-15-24-16.gh-issue-40889.TbsSM1.rst

@@ -0,0 +1 @@
+Fix :func:`email.utils.parseaddr` to handle routes with multiple intermediate hops.