4 unit tests failed with Python 3.14

[Jun Omae]

It seems the textwrap.dedent in Python 3.14 replaces CR LF line with LF line. I remove uses of textwrap.dedent from the failed tests.

======================================================================
ERROR: test_post_with_null_bytes_for_filename (trac.web.tests.api.RequestTestCase.test_post_with_null_bytes_for_filename)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/jun66j5/src/tracdev/git/trac/web/tests/api.py", line 600, in test_post_with_null_bytes_for_filename
    self._test_post_with_null_bytes(form_data)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^
  File "/home/jun66j5/src/tracdev/git/trac/web/tests/api.py", line 579, in _test_post_with_null_bytes
    req.args['action']
    ^^^^^^^^
  File "/home/jun66j5/src/tracdev/git/trac/web/api.py", line 689, in __getattr__
    value = self.callbacks[name](self)
  File "/home/jun66j5/src/tracdev/git/trac/web/api.py", line 671, in <lambda>
    'args': lambda req: arg_list_to_args(req.arg_list),
                                         ^^^^^^^^^^^^
  File "/home/jun66j5/src/tracdev/git/trac/web/api.py", line 689, in __getattr__
    value = self.callbacks[name](self)
  File "/home/jun66j5/src/tracdev/git/trac/web/api.py", line 1046, in _parse_arg_list
    return list(parse_form_data(self.environ))
  File "/home/jun66j5/src/tracdev/git/trac/web/api.py", line 535, in parse_form_data
    forms, files = multipart.parse_form_data(environ, charset='utf-8',
                   ~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^
                                             strict=True)
                                             ^^^^^^^^^^^^
  File "/home/jun66j5/venv/py314/lib/python3.14/site-packages/multipart.py", line 840, in parse_form_data
    for part in MultipartParser(stream, boundary, content_length, **kwargs):
                ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jun66j5/venv/py314/lib/python3.14/site-packages/multipart.py", line 622, in __iter__
    for part in self._part_iter:
                ^^^^^^^^^^^^^^^
  File "/home/jun66j5/venv/py314/lib/python3.14/site-packages/multipart.py", line 668, in _iterparse
    for event in parser.parse(chunk):
                 ~~~~~~~~~~~~^^^^^^^
  File "/home/jun66j5/venv/py314/lib/python3.14/site-packages/multipart.py", line 347, in parse
    self._current._add_headerline(buffer[offset:nl])
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^
  File "/home/jun66j5/venv/py314/lib/python3.14/site-packages/multipart.py", line 489, in _add_headerline
    raise self._fail("Malformed segment header")
          ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jun66j5/venv/py314/lib/python3.14/site-packages/multipart.py", line 406, in _fail
    raise err
multipart.MultipartError: Malformed segment header

----------------------------------------------------------------------
Ran 2817 tests in 33.141s

FAILED (errors=4, skipped=5)

test-textwrap.py

import textwrap

def main():
    form_data = textwrap.dedent("""\
        --%(boundary)s\r\n\
        Content-Disposition: form-data; name="attachment"; \
        filename="thefi\x00le.txt"\r\n\
        Content-Type: text/plain\r\n\
        \r\n\
        The file content.\r\n\
        --%(boundary)s\r\n\
        Content-Disposition: form-data; name="action"\r\n\
        \r\n\
        new\r\n\
        --%(boundary)s--\r\n\
        """)
    print(repr(form_data).replace('\\n', '\\n\n'))

if __name__ == '__main__':
    main()

diff between 3.13 and 3.14

$ diff -u <(python3.13 test-textwrap.py) <(python3.14 test-textwrap.py)
--- /dev/fd/63  2025-10-13 07:43:11.952061732 +0900
+++ /dev/fd/62  2025-10-13 07:43:11.952061732 +0900
@@ -1,11 +1,11 @@
 '--%(boundary)s\r\n
 Content-Disposition: form-data; name="attachment";         filename="thefi\x00le.txt"\r\n
 Content-Type: text/plain\r\n
-\r\n
+\n
 The file content.\r\n
 --%(boundary)s\r\n
 Content-Disposition: form-data; name="action"\r\n
-\r\n
+\n
 new\r\n
 --%(boundary)s--\r\n
 '

[Jun Omae]

Fixed in [17912] and merged in [17913].