Bug 2458668

python-metakernel fails to build with Python 3.15.0a8.

18 tests fail with the same issue: DeprecationWarning causing them to fail.

_______________________________ test_python_repl _______________________________

    @pytest.mark.skipif(
        sys.platform in ("win32", "darwin"),
        reason="python() requires a pty (not on Windows) and has REPL differences on macOS",
    )
    def test_python_repl() -> None:
        """python() starts a Python REPL that can evaluate expressions."""
>       repl = replwrap.python(sys.executable)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/builddir/build/BUILD/python-metakernel-1.0.2-build/metakernel-1.0.2/tests/test_replwrap_helpers.py:18: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
/builddir/build/BUILD/python-metakernel-1.0.2-build/metakernel-1.0.2/metakernel/replwrap.py:316: in python
    return REPLWrapper(
/builddir/build/BUILD/python-metakernel-1.0.2-build/metakernel-1.0.2/metakernel/replwrap.py:72: in __init__
    self.child = pexpect.spawnu(
/builddir/build/BUILD/python-metakernel-1.0.2-build/metakernel-1.0.2/metakernel/pexpect.py:75: in spawn
    child = pty_spawn(
/usr/lib/python3.15/site-packages/pexpect/pty_spawn.py:205: in __init__
    self._spawn(command, args, preexec_fn, dimensions)
/usr/lib/python3.15/site-packages/pexpect/pty_spawn.py:303: in _spawn
    self.ptyproc = self._spawnpty(self.args, env=self.env,
/usr/lib/python3.15/site-packages/pexpect/pty_spawn.py:315: in _spawnpty
    return ptyprocess.PtyProcess.spawn(args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
/usr/lib/python3.15/site-packages/ptyprocess/ptyprocess.py:230: in spawn
    pid, fd = pty.fork()
              ^^^^^^^^^^
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

    def fork():
        """fork() -> (pid, master_fd)
        Fork and make the child a session leader with a controlling terminal."""
    
        try:
>           pid, fd = os.forkpty()
                      ^^^^^^^^^^^^
E           DeprecationWarning: This process (pid=889) is multi-threaded, use of forkpty() may lead to deadlocks in the child.

https://docs.python.org/3.15/whatsnew/3.15.html

For the build logs, see:
https://copr-be.cloud.fedoraproject.org/results/@python/python3.15/fedora-rawhide-x86_64/10318742-python-metakernel/

For all our attempts to build python-metakernel with Python 3.15, see:
https://copr.fedorainfracloud.org/coprs/g/python/python3.15/package/python-metakernel/

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 3.15:
https://copr.fedorainfracloud.org/coprs/g/python/python3.15/

Let us know here if you have any questions.

Python 3.15 is planned to be included in Fedora 45.
To make that update smoother, we're building Fedora packages with all pre-releases of Python 3.15.
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.