From d256ffd20a8c341c91a2a6638aee1b02e46de4ab Mon Sep 17 00:00:00 2001 From: "R. David Murray" Date: Fri, 9 Oct 2026 08:54:09 -0400 Subject: [PATCH] gh-87720 Fix additional header refolding-quoting edge case (GH-134271) In this case, the higher level syntactic unit fit on the remainder of the line in un-encoded format, and that higher level unit was not a ptext or vtext, so the encoding check failed. To fix this, we look inside the current unit to see if has anything that was originally encoded. (cherry picked from commit 5a22a62b96a68c2dd31784c5e3427ad7b365388a) Co-authored-by: R. David Murray --- Lib/email/_header_value_parser.py | 13 ++++++++++++- Lib/test/test_email/test__header_value_parser.py | 5 +++++ .../2026-10-08-16-18-43.gh-issue-87720.Elqdl9.rst | 3 +++ 3 files changed, 20 insertions(+), 1 deletion(-) create mode 100644 Misc/NEWS.d/next/Library/2026-10-08-16-18-43.gh-issue-87720.Elqdl9.rst diff --git a/Lib/email/_header_value_parser.py b/Lib/email/_header_value_parser.py index 673dddcc20601e..2bdb65fe645b16 100644 --- a/Lib/email/_header_value_parser.py +++ b/Lib/email/_header_value_parser.py @@ -168,6 +168,14 @@ def comments(self): comments.extend(token.comments) return comments + def contains_token_type(self, *token_types): + if self.token_type in token_types: + return True + for t in self: + if t.contains_token_type(*token_types): + return True + return False + def fold(self, *, policy): return _refold_parse_tree(self, policy=policy) @@ -928,6 +936,9 @@ def pop_trailing_ws(self): def comments(self): return [] + def contains_token_type(self, *token_types): + return self.token_type in token_types + def __getnewargs__(self): return(str(self), self.token_type) @@ -2819,7 +2830,7 @@ def _refold_parse_tree(parse_tree, *, policy): continue tstr = str(part) if not want_encoding: - if part.token_type in ('ptext', 'vtext'): + if part.token_type == 'ptext' or part.contains_token_type('vtext'): # Encode if tstr contains special characters. want_encoding = not SPECIALSNL.isdisjoint(tstr) else: diff --git a/Lib/test/test_email/test__header_value_parser.py b/Lib/test/test_email/test__header_value_parser.py index c708479e2f5876..51ecdd4094c51d 100644 --- a/Lib/test/test_email/test__header_value_parser.py +++ b/Lib/test/test_email/test__header_value_parser.py @@ -3096,6 +3096,11 @@ def test_address_list_with_specials_in_encoded_word(self): 'A =?utf-8?q?v=C3=A9ry?= long name\n' ' containing =?utf-8?q?a=2C?= comma\n' ' \n'), + ('=?utf-8?Q?a=2C=20123456789012345678901234567890123456?=' + ' ', + '=?utf-8?q?a=2C?=\n' + ' 123456789012345678901234567890123456\n' + ' \n'), ] for (to, folded) in cases: with self.subTest(to=to): diff --git a/Misc/NEWS.d/next/Library/2026-10-08-16-18-43.gh-issue-87720.Elqdl9.rst b/Misc/NEWS.d/next/Library/2026-10-08-16-18-43.gh-issue-87720.Elqdl9.rst new file mode 100644 index 00000000000000..a2df7654b31444 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2026-10-08-16-18-43.gh-issue-87720.Elqdl9.rst @@ -0,0 +1,3 @@ +Fixed error in :mod:`email` new policies where header folding failed to +detect the need to re-quote text obtained from encoded words in certain +cases.