Merged upstream changes.

Lib/email/_header_value_parser.py

@@ -1624,6 +1624,7 @@ def get_quoted_string(value):
 def get_atom(value):
     """atom = [CFWS] 1*atext [CFWS]
 
+    An atom could be an rfc2047 encoded word.
     """
     atom = Atom()
     if value and value[0] in CFWS_LEADER:
@@ -1632,7 +1633,15 @@ def get_atom(value):
     if value and value[0] in ATOM_ENDS:
         raise errors.HeaderParseError(
             "expected atom but found '{}'".format(value))
-    token, value = get_atext(value)
+    if value.startswith('=?'):
+        try:
+            token, value = get_encoded_word(value)
+        except errors.HeaderParseError:
+            # XXX: need to figure out how to register defects when
+            # appropriate here.
+            token, value = get_atext(value)
+    else:
+        token, value = get_atext(value)
     atom.append(token)
     if value and value[0] in CFWS_LEADER:
         token, value = get_cfws(value)
@@ -1661,12 +1670,22 @@ def get_dot_atom_text(value):
 def get_dot_atom(value):
     """ dot-atom = [CFWS] dot-atom-text [CFWS]
 
+    Any place we can have a dot atom, we could instead have an rfc2047 encoded
+    word.
     """
     dot_atom = DotAtom()
     if value[0] in CFWS_LEADER:
         token, value = get_cfws(value)
         dot_atom.append(token)
-    token, value = get_dot_atom_text(value)
+    if value.startswith('=?'):
+        try:
+            token, value = get_encoded_word(value)
+        except errors.HeaderParseError:
+            # XXX: need to figure out how to register defects when
+            # appropriate here.
+            token, value = get_dot_atom_text(value)
+    else:
+        token, value = get_dot_atom_text(value)
     dot_atom.append(token)
     if value and value[0] in CFWS_LEADER:
         token, value = get_cfws(value)

Lib/test/test_email/test__header_value_parser.py

@@ -808,9 +808,13 @@ class TestParser(TestParserMixin, TestEmailBase):
         self.assertEqual(atom[2].comments, ['bar'])
 
     def test_get_atom_atom_ends_at_noncfws(self):
-        atom = self._test_get_x(parser.get_atom,
+        self._test_get_x(parser.get_atom,
             'bob  fred', 'bob  ', 'bob ', [], 'fred')
 
+    def test_get_atom_rfc2047_atom(self):
+        self._test_get_x(parser.get_atom,
+            '=?utf-8?q?=20bob?=', ' bob', ' bob', [], '')
+
     # get_dot_atom_text
 
     def test_get_dot_atom_text(self):
@@ -885,6 +889,10 @@ class TestParser(TestParserMixin, TestEmailBase):
         with self.assertRaises(errors.HeaderParseError):
             parser.get_dot_atom(' (foo) bar.bang. foo')
 
+    def test_get_dot_atom_rfc2047_atom(self):
+        self._test_get_x(parser.get_dot_atom,
+            '=?utf-8?q?=20bob?=', ' bob', ' bob', [], '')
+
     # get_word (if this were black box we'd repeat all the qs/atom tests)
 
     def test_get_word_atom_yields_atom(self):
@@ -2156,6 +2164,22 @@ class TestParser(TestParserMixin, TestEmailBase):
         self.assertEqual(address[0].token_type,
                          'mailbox')
 
+    def test_get_address_rfc2047_display_name(self):
+        address = self._test_get_x(parser.get_address,
+            '=?utf-8?q?=C3=89ric?= <foo@example.com>',
+            'Éric <foo@example.com>',
+            'Éric <foo@example.com>',
+            [],
+            '')
+        self.assertEqual(address.token_type, 'address')
+        self.assertEqual(len(address.mailboxes), 1)
+        self.assertEqual(address.mailboxes,
+                         address.all_mailboxes)
+        self.assertEqual(address.mailboxes[0].display_name,
+                         'Éric')
+        self.assertEqual(address[0].token_type,
+                         'mailbox')
+
     def test_get_address_empty_group(self):
         address = self._test_get_x(parser.get_address,
             'Monty Python:;',

Lib/test/test_email/test_headerregistry.py

@@ -158,6 +158,10 @@ class TestUnstructuredHeader(TestHeaderBase):
             '=?utf-8?q?=C3=89ric?=',
             'Éric'),
 
+        'rfc2047_quopri_with_regular_text': (
+            'The =?utf-8?q?=C3=89ric=2C?= Himself',
+            'The Éric, Himself'),
+
     }
 
 
@@ -1119,6 +1123,26 @@ class TestAddressHeader(TestHeaderBase):
              'example.com',
              None),
 
+        'rfc2047_atom_is_decoded':
+            ('=?utf-8?q?=C3=89ric?= <foo@example.com>',
+            [],
+            'Éric <foo@example.com>',
+            'Éric',
+            'foo@example.com',
+            'foo',
+            'example.com',
+            None),
+
+        'rfc2047_atom_in_phrase_is_decoded':
+            ('The =?utf-8?q?=C3=89ric=2C?= Himself <foo@example.com>',
+            [],
+            '"The Éric, Himself" <foo@example.com>',
+            'The Éric, Himself',
+            'foo@example.com',
+            'foo',
+            'example.com',
+            None),
+
         }
 
         # XXX: Need many more examples, and in particular some with names in

Misc/NEWS

@@ -154,6 +154,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #18431: The new email header parser now decodes RFC2047 encoded words
+  in structured headers.
+
 - Issue #18044: The new email header parser was mis-parsing encoded words where
   an encoded character immediately followed the '?' that follows the CTE
   character, resulting in a decoding failure.  They are now decoded correctly.