python-stack-data fails to build with Python 3.14.05.

_________________________________ test_example _________________________________

capsys = <_pytest.capture.CaptureFixture object at 0x7f909fc3ecf0>

    def test_example(capsys):
        from .samples.formatter_example import bar, print_stack1, format_stack1, format_frame, f_string, blank_lines
    
        @contextmanager
        def check_example(name):
            yield
            stderr = capsys.readouterr().err
            compare_to_file(stderr, name)
    
        with check_example("variables"):
            try:
                bar()
            except Exception:
                MyFormatter(show_variables=True).print_exception()
    
        with check_example("pygmented"):
            try:
                bar()
            except Exception:
                MyFormatter(pygmented=True).print_exception()
    
        with check_example("plain"):
            MyFormatter().set_hook()
            try:
                bar()
            except Exception:
                sys.excepthook(*sys.exc_info())
    
        with check_example("pygmented_error"):
            h = pygments.highlight
            pygments.highlight = lambda *args, **kwargs: 1/0
            try:
                bar()
            except Exception:
                MyFormatter(pygmented=True).print_exception()
            finally:
                pygments.highlight = h
    
        with check_example("print_stack"):
            print_stack1(MyFormatter())
    
        with check_example("format_stack"):
            formatter = MyFormatter()
            formatted = format_stack1(formatter)
            formatter.print_lines(formatted)
    
        with check_example("format_frame"):
            formatter = BaseFormatter()
            formatted = format_frame(formatter)
            formatter.print_lines(formatted)
    
        if sys.version_info[:2] < (3, 8):
            f_string_suffix = 'old'
        elif not fstring_positions_work():
            f_string_suffix = '3.8'
        else:
            f_string_suffix = 'new'
    
        with check_example(f"f_string_{f_string_suffix}"):
            try:
                f_string()
            except Exception:
                MyFormatter().print_exception()
    
        from .samples.formatter_example import block_right, block_left
    
        with check_example(f"block_right_{'old' if sys.version_info[:2] < (3, 8) else 'new'}"):
            try:
                block_right()
            except Exception:
                MyFormatter().print_exception()
    
        with check_example(f"block_left_{'old' if sys.version_info[:2] < (3, 8) else 'new'}"):
            try:
                block_left()
            except Exception:
                MyFormatter().print_exception()
    
        from .samples import cython_example
    
        with check_example("cython_example"):
            try:
                cython_example.foo()
            except Exception:
                MyFormatter().print_exception()
    
>       with check_example("blank_visible"):

tests/test_formatter.py:119: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
/usr/lib64/python3.14/contextlib.py:148: in __exit__
    next(self.gen)
tests/test_formatter.py:40: in check_example
    compare_to_file(stderr, name)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

text = 'Traceback (most recent call last):\n File "formatter_example.py", line 85, in blank_lines\n      79 | def blank_lines...     length = len(a)\n      83 | \n      84 | \n-->   85 |     return a[length]\nIndexError: list index out of range\n'
name = 'blank_visible'

    def compare_to_file(text, name):
        if old_pygments and "pygment" in name:
            return
        filename = os.path.join(
            os.path.dirname(__file__),
            'golden_files',
            name + '.txt',
        )
        if os.environ.get('FIX_STACK_DATA_TESTS'):
            string_to_file(text, filename)
        else:
            expected_output = file_to_string(filename)
>           assert text == expected_output
E           AssertionError

tests/utils.py:26: AssertionError

https://docs.python.org/3.14/whatsnew/3.14.html

For the build logs, see:
https://copr-be.cloud.fedoraproject.org/results/@python/python3.14/fedora-rawhide-x86_64/08651107-python-stack-data/

For all our attempts to build python-stack-data with Python 3.14, see:
https://copr.fedorainfracloud.org/coprs/g/python/python3.14/package/python-stack-data/

Testing and mass rebuild of packages is happening in copr.
You can follow these instructions to test locally in mock if your package builds with Python 3.14:
https://copr.fedorainfracloud.org/coprs/g/python/python3.14/

Let us know here if you have any questions.

Python 3.14 is planned to be included in Fedora 43.
To make that update smoother, we're building Fedora packages with all pre-releases of Python 3.14.
A build failure prevents us from testing all dependent packages (transitive [Build]Requires),
so if this package is required a lot, it's important for us to get it fixed soon.

We'd appreciate help from the people who know this package best,
but if you don't want to work on this now, let us know so we can try to work around it on our side.