cpython/Misc/NEWS.d/3.13.0b4.rst

.. date: 2024-07-04-15-10-29
.. gh-issue: 121084
.. nonce: qxcd5d
.. release date: 2024-07-18
.. section: Tests

Fix test_typing random leaks. Clear typing ABC caches when running tests for
refleaks (``-R`` option): call ``_abc_caches_clear()`` on typing abstract
classes and their subclasses. Patch by Victor Stinner.

..

.. date: 2024-07-03-14-41-00
.. gh-issue: 121160
.. nonce: LEtiTd
.. section: Tests

Add a test for :func:`readline.set_history_length`. Note that this test may
fail on readline libraries.

..

.. date: 2024-07-01-16-15-06
.. gh-issue: 121200
.. nonce: 4Pc-gc
.. section: Tests

Fix ``test_expanduser_pwd2()`` of ``test_posixpath``.  Call ``getpwnam()``
to get ``pw_dir``, since it can be different than ``getpwall()`` ``pw_dir``.
Patch by Victor Stinner.

..

.. date: 2024-07-01-09-04-32
.. gh-issue: 121188
.. nonce: XbuTVa
.. section: Tests

When creating the JUnit XML file, regrtest now escapes characters which are
invalid in XML, such as the chr(27) control character used in ANSI escape
sequences. Patch by Victor Stinner.

..

.. date: 2024-07-14-06-24-02
.. gh-issue: 57141
.. nonce: C3jhDh
.. section: Library

The *shallow* argument to :class:`filecmp.dircmp` (new in Python 3.13) is
now keyword-only.

..

.. date: 2024-07-13-06-23-24
.. gh-issue: 121245
.. nonce: RfOgf4
.. section: Library

Simplify handling of the history file in ``site.register_readline()``
helper. The ``CAN_USE_PYREPL`` variable now will be initialized, when
imported.  Patch by Sergey B Kirpichev.

..

.. date: 2024-07-03-07-25-21
.. gh-issue: 121332
.. nonce: Iz6FEq
.. section: Library

Fix constructor of :mod:`ast` nodes with custom ``_attributes``. Previously,
passing custom attributes would raise a :py:exc:`DeprecationWarning`.
Passing arguments to the constructor that are not in ``_fields`` or
``_attributes`` remains deprecated. Patch by Jelle Zijlstra.

..

.. date: 2024-07-02-19-36-54
.. gh-issue: 121279
.. nonce: BltDo9
.. section: Library

Avoid :exc:`NameError` for the :mod:`warnings` module when accessing the
depracated atributes of the :mod:`importlib.abc` module.

..

.. date: 2024-07-02-11-34-06
.. gh-issue: 121245
.. nonce: sSkDAr
.. section: Library

Fix a bug in the handling of the command history of the new :term:`REPL`
that caused the history file to be wiped at REPL exit.

..

.. date: 2024-06-29-05-08-59
.. gh-issue: 87744
.. nonce: rpF6Jw
.. section: Library

Fix waitpid race while calling
:meth:`~asyncio.subprocess.Process.send_signal` in asyncio. Patch by Kumar
Aditya.

..

.. date: 2024-06-26-03-04-24
.. gh-issue: 121018
.. nonce: clVSc4
.. section: Library

Fixed other issues where :class:`argparse.ArgumentParser` did not honor
``exit_on_error=False``.

..

.. date: 2024-06-22-17-01-56
.. gh-issue: 120678
.. nonce: Ik8dCg
.. section: Library

Fix regression in the new REPL that meant that globals from files passed
using the ``-i`` argument would not be included in the REPL's global
namespace. Patch by Alex Waygood.

..

.. date: 2024-06-21-12-00-16
.. gh-issue: 120782
.. nonce: LOE8tj
.. section: Library

Fix wrong references of the :mod:`datetime` types after reloading the
module.

..

.. date: 2024-06-21-06-37-46
.. gh-issue: 120713
.. nonce: WBbQx4
.. section: Library

:meth:`datetime.datetime.strftime` now 0-pads years with less than four
digits for the format specifiers ``%Y`` and ``%G`` on Linux. Patch by Ben
Hsing

..

.. date: 2024-06-07-10-10-32
.. gh-issue: 117983
.. nonce: NeMR9n
.. section: Library

Defer the ``threading`` import in ``importlib.util`` until lazy loading is
used.

..

.. date: 2024-05-20-13-48-37
.. gh-issue: 119189
.. nonce: dhJVs5
.. section: Library

When using the ``**`` operator or :func:`pow` with
:class:`~fractions.Fraction` as the base and an exponent that is not
rational, a float, or a complex, the fraction is no longer converted to a
float.

..

.. date: 2024-05-07-17-38-53
.. gh-issue: 118714
.. nonce: XXKpVZ
.. section: Library

Allow ``restart`` in post-mortem debugging of :mod:`pdb`. Removed restart
message when the user quits pdb from post-mortem mode.

..

.. date: 2023-06-17-09-07-06
.. gh-issue: 105623
.. nonce: 5G06od
.. section: Library

Fix performance degradation in
:class:`logging.handlers.RotatingFileHandler`. Patch by Craig Robson.

..

.. date: 2024-07-16-16-57-03
.. gh-issue: 78889
.. nonce: U7ghFD
.. section: IDLE

Stop Shell freezes by blocking user access to non-method sys.stdout.shell
attributes, which are all private.

..

.. date: 2024-07-14-11-48-10
.. gh-issue: 121749
.. nonce: nxHoTk
.. section: Documentation

Fix documentation for :c:func:`PyModule_AddObjectRef`.

..

.. date: 2024-06-05-12-36-18
.. gh-issue: 120012
.. nonce: f14DbQ
.. section: Documentation

Clarify the behaviours of :meth:`multiprocessing.Queue.empty` and
:meth:`multiprocessing.SimpleQueue.empty` on closed queues. Patch by
Bénédikt Tran.

..

.. date: 2024-07-16-18-23-22
.. gh-issue: 121860
.. nonce: -FTauD
.. section: Core and Builtins

Fix crash when rematerializing a managed dictionary after it was deleted.

..

.. date: 2024-07-15-20-41-06
.. gh-issue: 121814
.. nonce: oR2ixR
.. section: Core and Builtins

Fixed the SegFault when :c:func:`PyEval_SetTrace` is used with no Python
frame on stack.

..

.. date: 2024-07-15-20-03-29
.. gh-issue: 121295
.. nonce: w53ucI
.. section: Core and Builtins

Fix PyREPL console getting into a blocked state after interrupting a long
paste

..

.. date: 2024-07-15-16-26-32
.. gh-issue: 121794
.. nonce: fhBtiQ
.. section: Core and Builtins

Fix bug in free-threaded Python where a resurrected object could lead to a
negative ref count assertion failure.

..

.. date: 2024-07-13-12-27-31
.. gh-issue: 121657
.. nonce: wgOYLw
.. section: Core and Builtins

Improve the :exc:`SyntaxError` message if the user tries to use
:keyword:`yield from <yield>` outside a function.

..

.. date: 2024-07-13-09-51-44
.. gh-issue: 121609
.. nonce: jWsE5t
.. section: Core and Builtins

Fix pasting of characters containing unicode character joiners in the new
REPL. Patch by Marta Gomez Macias

..

.. date: 2024-07-10-15-43-54
.. gh-issue: 117482
.. nonce: 5WYaXR
.. section: Core and Builtins

Unexpected slot wrappers are no longer created for builtin static types in
subinterpreters.

..

.. date: 2024-07-09-13-53-18
.. gh-issue: 121499
.. nonce: rpp7il
.. section: Core and Builtins

Fix a bug affecting how multi-line history was being rendered in the new
REPL after interacting with the new screen cache. Patch by Pablo Galindo

..

.. date: 2024-07-08-17-15-14
.. gh-issue: 121497
.. nonce: I8hMDC
.. section: Core and Builtins

Fix a bug that was preventing the REPL to correctly respect the history when
an input hook was set. Patch by Pablo Galindo

..

.. date: 2024-07-08-10-31-08
.. gh-issue: 121012
.. nonce: M5hHk-
.. section: Core and Builtins

Tier 2 execution now ensures that list iterators remain exhausted, once they
become exhausted.

..

.. date: 2024-07-08-02-24-55
.. gh-issue: 121439
.. nonce: jDHod3
.. section: Core and Builtins

Allow tuples of length 20 in the freelist to be reused.

..

.. date: 2024-07-04-23-38-30
.. gh-issue: 121368
.. nonce: m3EF9E
.. section: Core and Builtins

Fix race condition in ``_PyType_Lookup`` in the free-threaded build due to a
missing memory fence.  This could lead to ``_PyType_Lookup`` returning
incorrect results on arm64.

..

.. date: 2024-06-29-10-46-14
.. gh-issue: 121130
.. nonce: Rj66Xs
.. section: Core and Builtins

Fix f-strings with debug expressions in format specifiers. Patch by Pablo
Galindo

..

.. date: 2024-06-28-10-02-58
.. gh-issue: 121115
.. nonce: EeSLfc
.. section: Core and Builtins

:c:func:`PyLong_AsNativeBytes` no longer uses :meth:`~object.__index__`
methods by default. The ``Py_ASNATIVEBYTES_ALLOW_INDEX`` flag has been added
to allow it.

..

.. date: 2024-07-09-15-55-20
.. gh-issue: 89364
.. nonce: yYYroI
.. section: C API

Export the :c:func:`PySignal_SetWakeupFd` function. Previously, the function
was documented but it couldn't be used in 3rd party code. Patch by Victor
Stinner.

..

.. date: 2024-07-04-15-41-10
.. gh-issue: 113993
.. nonce: cLSiWV
.. section: C API

:c:func:`PyUnicode_InternInPlace` no longer prevents its argument from being
garbage collected.

Several functions that take ``char *`` are now documented as possibly
preventing string objects from being garbage collected; refer to their
documentation for details: :c:func:`PyUnicode_InternFromString`,
:c:func:`PyDict_SetItemString`, :c:func:`PyObject_SetAttrString`,
:c:func:`PyObject_DelAttrString`, :c:func:`PyUnicode_InternFromString`, and
``PyModule_Add*`` convenience functions.

..

.. date: 2024-07-04-13-23-27
.. gh-issue: 113601
.. nonce: K3RLqp
.. section: C API

Removed debug build assertions related to interning strings, which were
falsely triggered by stable ABI extensions.

..

.. date: 2024-07-02-11-03-40
.. gh-issue: 112136
.. nonce: f3fiY8
.. section: C API

Restore the private ``_PyArg_Parser`` structure and the private
``_PyArg_ParseTupleAndKeywordsFast()`` function, previously removed in
Python 3.13 alpha 1. Patch by Victor Stinner.

..

.. date: 2024-07-16-12-29-54
.. gh-issue: 120371
.. nonce: E7x858
.. section: Build

Support WASI SDK 22 by explicitly skipping functions that are just stubs in
wasi-libc.

..

.. date: 2024-07-14-01-29-47
.. gh-issue: 121731
.. nonce: RMPGP3
.. section: Build

Fix mimalloc compile error on GNU/Hurd

..

.. date: 2024-07-08-14-01-17
.. gh-issue: 121487
.. nonce: ekHmpR
.. section: Build

Fix deprecation warning for ATOMIC_VAR_INIT in mimalloc.

..

.. date: 2024-07-08-01-11-54
.. gh-issue: 121467
.. nonce: 3qWRQj
.. section: Build

Fix a Makefile bug that prevented mimalloc header files from being
installed.

..

.. date: 2024-07-02-20-16-09
.. gh-issue: 121103
.. nonce: TMef9j
.. section: Build

On POSIX systems, excluding macOS framework installs, the lib directory for
the free-threaded build now includes a "t" suffix to avoid conflicts with a
co-located default build installation.

..

.. date: 2024-07-02-12-42-25
.. gh-issue: 120831
.. nonce: i3eIjg
.. section: Build

The default minimum iOS version was increased to 13.0.

..

.. date: 2024-06-02-13-23-26
.. gh-issue: 113565
.. nonce: 8xBlId
.. section: Build

Improve :mod:`curses` and :mod:`curses.panel` dependency checks in
:program:`configure`.