gh-135307: Fix email error when policy max_line_length is set to 0 or None (#135367)

RDM: Like the change made in a earlier PR to the folder, we can/must use 'maxlen' as a stand in for 'unlimited' when computing line lengths when max_line_length is 0 or None; otherwise the computation results in a traceback.
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Jiucheng(Oliver) 2025-11-02 09:32:14 -05:00 committed by GitHub
parent 173cc53d9f
commit 6d45cd8dbb
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3 changed files with 35 additions and 5 deletions

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@ -1004,6 +1004,32 @@ def test_folding_with_long_nospace_http_policy_1(self):
parsed_msg = message_from_bytes(m.as_bytes(), policy=policy.default)
self.assertEqual(parsed_msg['Message-ID'], m['Message-ID'])
def test_no_wrapping_max_line_length(self):
# Test that falsey 'max_line_length' are converted to sys.maxsize.
for n in [0, None]:
with self.subTest(max_line_length=n):
self.do_test_no_wrapping_max_line_length(n)
def do_test_no_wrapping_max_line_length(self, falsey):
self.assertFalse(falsey)
pol = policy.default.clone(max_line_length=falsey)
subj = "S" * 100
body = "B" * 100
msg = EmailMessage(policy=pol)
msg["From"] = "a@ex.com"
msg["To"] = "b@ex.com"
msg["Subject"] = subj
msg.set_content(body)
raw = msg.as_bytes()
self.assertNotIn(b"=\n", raw,
"Found fold indicator; wrapping not disabled")
parsed = message_from_bytes(raw, policy=policy.default)
self.assertEqual(parsed["Subject"], subj)
parsed_body = parsed.get_body().get_content().rstrip('\n')
self.assertEqual(parsed_body, body)
def test_invalid_header_names(self):
invalid_headers = [
('Invalid Header', 'contains space'),