path: root/Misc/NEWS.d/3.13.0b3.rst

.. date: 2024-06-26-14-09-31
.. gh-issue: 120838
.. nonce: nFeTL9
.. release date: 2024-06-27
.. section: Core and Builtins

:c:func:`Py_Finalize()` and :c:func:`Py_FinalizeEx()` now always run with
the main interpreter active.

..

.. date: 2024-06-26-13-42-36
.. gh-issue: 113433
.. nonce: xKAtLB
.. section: Core and Builtins

Subinterpreters now get cleaned up automatically during runtime
finalization.

..

.. date: 2024-06-19-11-10-50
.. gh-issue: 119462
.. nonce: DpcqSe
.. section: Core and Builtins

Make sure that invariants of type versioning are maintained: * Superclasses
always have their version number assigned before subclasses * The version
tag is always zero if the tag is not valid. * The version tag is always
non-zero if the tag is valid.

..

.. date: 2024-06-19-01-58-54
.. gh-issue: 120437
.. nonce: nCkIoI
.. section: Core and Builtins

Fix ``_CHECK_STACK_SPACE`` optimization problems introduced in :gh:`118322`.

..

.. date: 2024-06-18-22-41-05
.. gh-issue: 120722
.. nonce: rS7tkE
.. section: Core and Builtins

Correctly set the bytecode position on return instructions within lambdas.
Patch by Jelle Zijlstra.

..

.. date: 2024-06-18-21-34-30
.. gh-issue: 120367
.. nonce: zDwffP
.. section: Core and Builtins

Fix bug where compiler creates a redundant jump during pseudo-op
replacement. Can only happen with a synthetic AST that has a try on the same
line as the instruction following the exception handler.

..

.. date: 2024-06-14-22-02-25
.. gh-issue: 113993
.. nonce: MiA0vX
.. section: Core and Builtins

Strings interned with :func:`sys.intern` are again garbage-collected when no
longer used, as per the documentation. Strings interned with the C function
:c:func:`PyUnicode_InternInPlace` are still immortal. Internals of the
string interning mechanism have been changed. This may affect performance
and identities of :class:`str` objects.

..

.. date: 2024-06-13-12-17-52
.. gh-issue: 120384
.. nonce: w1UBGl
.. section: Core and Builtins

Fix an array out of bounds crash in ``list_ass_subscript``, which could be
invoked via some specificly tailored input: including concurrent
modification of a list object, where one thread assigns a slice and another
clears it.

..

.. date: 2024-06-12-18-50-29
.. gh-issue: 120367
.. nonce: LmXx2y
.. section: Core and Builtins

Fix crash in compiler on code with redundant NOPs and JUMPs which show up
after exception handlers are moved to the end of the code.

..

.. date: 2024-06-12-18-23-15
.. gh-issue: 120380
.. nonce: edtqjq
.. section: Core and Builtins

Fix Python implementation of :class:`pickle.Pickler` for :class:`bytes` and
:class:`bytearray` objects when using protocol version 5. Patch by Bénédikt
Tran.

..

.. date: 2024-06-12-12-29-45
.. gh-issue: 120400
.. nonce: lZYHVS
.. section: Core and Builtins

Support Linux perf profiler to see Python calls on RISC-V architecture.

..

.. date: 2024-06-11-17-56-12
.. gh-issue: 120221
.. nonce: si9hM9
.. section: Core and Builtins

Deliver real signals on Ctrl-C and Ctrl-Z in the new REPL. Patch by Pablo
Galindo

..

.. date: 2024-06-11-12-47-54
.. gh-issue: 120346
.. nonce: hhn_6X
.. section: Core and Builtins

Respect :envvar:`PYTHON_BASIC_REPL` when running in interative inspect mode
(``python -i``). Patch by Pablo Galindo

..

.. date: 2024-06-10-22-30-26
.. gh-issue: 93691
.. nonce: 68WOTS
.. section: Core and Builtins

Fix source locations of instructions generated for the iterator of a for
statement.

..

.. date: 2024-06-10-15-07-16
.. gh-issue: 120198
.. nonce: WW_pjO
.. section: Core and Builtins

Fix a crash when multiple threads read and write to the same ``__class__``
of an object concurrently.

..

.. date: 2024-06-10-10-42-48
.. gh-issue: 120298
.. nonce: napREA
.. section: Core and Builtins

Fix use-after free in ``list_richcompare_impl`` which can be invoked via
some specificly tailored evil input.

..

.. date: 2024-06-09-19-13-38
.. gh-issue: 119666
.. nonce: S0G4rZ
.. section: Core and Builtins

Fix a compiler crash in the case where two comprehensions in class scope
both reference ``__class__``.

..

.. date: 2024-06-07-16-09-04
.. gh-issue: 120225
.. nonce: kuYf9t
.. section: Core and Builtins

Fix crash in compiler on empty block at end of exception handler.

..

.. date: 2024-06-03-13-48-44
.. gh-issue: 119933
.. nonce: Kc0HG5
.. section: Core and Builtins

Improve :exc:`SyntaxError` messages for invalid expressions in a type
parameters bound, a type parameter constraint tuple or a default type
parameter. Patch by Bénédikt Tran.

..

.. bpo: 24766
.. date: 2018-10-09-15-14-53
.. nonce: c_C1Wc
.. section: Core and Builtins

Fix handling of ``doc`` argument to subclasses of ``property``.

..

.. date: 2024-06-27-13-47-14
.. gh-issue: 121027
.. nonce: jh55EC
.. section: Library

Add a future warning in :meth:`!functools.partial.__get__`. In future Python
versions :class:`functools.partial` will be a method descriptor.

..

.. date: 2024-06-26-10-13-40
.. gh-issue: 121025
.. nonce: M-XXlV
.. section: Library

Improve the :meth:`~object.__repr__` of :class:`functools.partialmethod`.
Patch by Bénédikt Tran.

..

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

Fixed an issue where :meth:`!argparse.ArgumentParser.parses_args` did not
honor ``exit_on_error=False`` when given unrecognized arguments. Patch by
Ben Hsing.

..

.. date: 2024-06-23-17-50-40
.. gh-issue: 119614
.. nonce: vwPGLB
.. section: Library

Fix truncation of strings with embedded null characters in some internal
operations in :mod:`tkinter`.

..

.. date: 2024-06-23-11-21-27
.. gh-issue: 120910
.. nonce: t0QXdB
.. section: Library

When reading installed files from an egg, use ``relative_to(walk_up=True)``
to honor files installed outside of the installation root.

..

.. date: 2024-06-22-22-52-24
.. gh-issue: 120888
.. nonce: sd8I3N
.. section: Library

Upgrade pip wheel bundled with ensurepip (pip 24.1.1)

..

.. date: 2024-06-22-22-23-56
.. gh-issue: 101830
.. nonce: 1BAoxH
.. section: Library

Accessing the :mod:`tkinter` object's string representation no longer
converts the underlying Tcl object to a string on Windows.

..

.. date: 2024-06-21-14-32-56
.. gh-issue: 120811
.. nonce: eBmVTV
.. section: Library

Fix possible memory leak in :meth:`contextvars.Context.run`.

..

.. date: 2024-06-20-01-31-24
.. gh-issue: 120769
.. nonce: PfiMrc
.. section: Library

Make empty line in :mod:`pdb` repeats the last command even when the command
is from ``cmdqueue``.

..

.. date: 2024-06-19-15-06-58
.. gh-issue: 120732
.. nonce: OvYV9b
.. section: Library

Fix ``name`` passing to :class:`unittest.mock.Mock` object when using
:func:`unittest.mock.create_autospec`.

..

.. date: 2024-06-18-19-18-10
.. gh-issue: 120683
.. nonce: xmRez7
.. section: Library

Fix an error in :class:`logging.LogRecord`, when the integer part of the
timestamp is rounded up, while the millisecond calculation truncates,
causing the log timestamp to be wrong by up to 999 ms (affected roughly 1 in
8 million timestamps).

..

.. date: 2024-06-17-20-04-13
.. gh-issue: 120633
.. nonce: kZC5wt
.. section: Library

Move scrollbar and remove tear-off menus in turtledemo.

..

.. date: 2024-06-15-12-04-46
.. gh-issue: 120541
.. nonce: d3cc5y
.. section: Library

Improve the prompt in the "less" pager when :func:`help` is called with
non-string argument.

..

.. date: 2024-06-14-20-05-25
.. gh-issue: 120495
.. nonce: OxgZKB
.. section: Library

Fix incorrect exception handling in Tab Nanny. Patch by Wulian233.

..

.. date: 2024-06-12-11-54-05
.. gh-issue: 120381
.. nonce: O-BNLs
.. section: Library

Correct :func:`inspect.ismethoddescriptor` to check also for the lack of
:meth:`~object.__delete__`.  Patch by Jan Kaliszewski.

..

.. date: 2024-06-12-10-00-31
.. gh-issue: 90425
.. nonce: 5CfkKG
.. section: Library

The OS byte in gzip headers is now always set to 255 when using
:func:`gzip.compress`.

..

.. date: 2024-06-11-16-34-41
.. gh-issue: 120343
.. nonce: hdiXeU
.. section: Library

Fix column offset reporting for tokens that come after multiline f-strings
in the :mod:`tokenize` module.

..

.. date: 2024-06-10-14-00-40
.. gh-issue: 119600
.. nonce: jJMf4C
.. section: Library

Fix :func:`unittest.mock.patch` to not read attributes of the target when
``new_callable`` is set. Patch by Robert Collins.

..

.. date: 2024-06-08-15-46-35
.. gh-issue: 114053
.. nonce: Ub2XgJ
.. section: Library

Fix edge-case bug where :func:`typing.get_type_hints` would produce
incorrect results if type parameters in a class scope were overridden by
assignments in a class scope and ``from __future__ import annotations``
semantics were enabled. Patch by Alex Waygood.

..

.. date: 2024-06-08-15-15-29
.. gh-issue: 114053
.. nonce: WQLAFG
.. section: Library

Fix erroneous :exc:`NameError` when calling :func:`inspect.get_annotations`
with ``eval_str=True``` on a class that made use of :pep:`695` type
parameters in a module that had ``from __future__ import annotations`` at
the top of the file. Patch by Alex Waygood.

..

.. date: 2024-06-08-14-36-40
.. gh-issue: 120268
.. nonce: MNpd1q
.. section: Library

Prohibit passing ``None`` to pure-Python :meth:`datetime.date.fromtimestamp`
to achieve consistency with C-extension implementation.

..

.. date: 2024-06-08-09-45-31
.. gh-issue: 120244
.. nonce: 8o9Dzr
.. section: Library

Fix memory leak in :func:`re.sub()` when the replacement string contains
backreferences.

..

.. date: 2024-06-07-13-21-11
.. gh-issue: 120211
.. nonce: Rws_gf
.. section: Library

Fix :mod:`tkinter.ttk` with Tcl/Tk 9.0.

..

.. date: 2024-06-07-11-23-31
.. gh-issue: 71587
.. nonce: IjFajE
.. section: Library

Fix crash in C version of :meth:`datetime.datetime.strptime` when called
again on the restarted interpreter.

..

.. date: 2024-06-06-17-24-43
.. gh-issue: 120161
.. nonce: DahNXV
.. section: Library

:mod:`datetime` no longer crashes in certain complex reference cycle
situations.

..

.. date: 2024-06-06-12-07-57
.. gh-issue: 119698
.. nonce: rRrprk
.. section: Library

Fix :meth:`symtable.Class.get_methods` and document its behaviour. Patch by
Bénédikt Tran.

..

.. date: 2024-06-05-16-30-28
.. gh-issue: 120121
.. nonce: 9dz8i7
.. section: Library

Add :exc:`concurrent.futures.InvalidStateError` to module's ``__all__``.

..

.. date: 2024-06-05-11-39-21
.. gh-issue: 119933
.. nonce: ooJXQV
.. section: Library

Add the :class:`symtable.SymbolTableType` enumeration to represent the
possible outputs of the :class:`symtable.SymbolTable.get_type` method. Patch
by Bénédikt Tran.

..

.. date: 2024-06-05-08-02-46
.. gh-issue: 120108
.. nonce: 4U9BL8
.. section: Library

Fix calling :func:`copy.deepcopy` on :mod:`ast` trees that have been
modified to have references to parent nodes. Patch by Jelle Zijlstra.

..

.. date: 2024-06-04-19-03-25
.. gh-issue: 112672
.. nonce: K2XfZH
.. section: Library

Support building :mod:`tkinter` with Tcl 9.0.

..

.. date: 2024-06-04-08-57-02
.. gh-issue: 65454
.. nonce: o9j4wF
.. section: Library

:func:`unittest.mock.Mock.attach_mock` no longer triggers a call to a
``PropertyMock`` being attached.

..

.. date: 2024-06-02-13-35-11
.. gh-issue: 81936
.. nonce: ETeW9x
.. section: Library

:meth:`!help` and :meth:`!showtopic` methods now respect a configured
*output* argument to :class:`!pydoc.Helper` and not use the pager in such
cases. Patch by Enrico Tröger.

..

.. date: 2024-05-29-21-50-05
.. gh-issue: 119577
.. nonce: S3BlKJ
.. section: Library

The :exc:`DeprecationWarning` emitted when testing the truth value of an
:class:`xml.etree.ElementTree.Element` now describes unconditionally
returning ``True`` in a future version rather than raising an exception in
Python 3.14.

..

.. date: 2024-05-25-10-40-38
.. gh-issue: 118908
.. nonce: XcZiq4
.. section: Library

Limit exposed globals from internal imports and definitions on new REPL
startup. Patch by Eugene Triguba and Pablo Galindo.

..

.. date: 2024-05-24-14-32-24
.. gh-issue: 119506
.. nonce: -nMNqq
.. section: Library

Fix :meth:`!io.TextIOWrapper.write` method breaks internal buffer when the
method is called again during flushing internal buffer.

..

.. date: 2024-06-21-09-24-03
.. gh-issue: 120671
.. nonce: Z8sBQB
.. section: Build

Fix failing configure tests due to a missing space when appending to CFLAGS.

..

.. date: 2024-06-19-21-05-15
.. gh-issue: 120602
.. nonce: UyDARz
.. section: Build

Correctly handle LLVM installs with ``LLVM_VERSION_SUFFIX`` when building
with ``--enable-experimental-jit``.

..

.. date: 2024-06-11-00-38-05
.. gh-issue: 120326
.. nonce: JHSDF1
.. section: Build

On Windows, fix build error when ``--disable-gil`` and
``--experimental-jit`` options are combined.

..

.. date: 2024-06-09-15-54-22
.. gh-issue: 120291
.. nonce: IpfHzE
.. section: Build

Make the ``python-config`` shell script compatible with non-bash shells.

..

.. date: 2024-06-26-11-29-01
.. gh-issue: 120642
.. nonce: H7P9qK
.. section: C API

Remove the private ``_Py_CODEUNIT`` type from the public C API. The internal
``pycore_code.h`` header should now be used to get this internal type. Patch
by Victor Stinner.

..

.. date: 2024-06-21-16-41-21
.. gh-issue: 120858
.. nonce: Z5_-Mn
.. section: C API

:c:func:`PyDict_Next` no longer locks the dictionary in the free-threaded
build.  The locking needs to be done by the caller around the entire
iteration loop.

..

.. date: 2024-06-19-21-27-42
.. gh-issue: 120642
.. nonce: UlKClN
.. section: C API

Remove the following unstable functions:

* ``PyUnstable_Replace_Executor()``
* ``PyUnstable_SetOptimizer()``
* ``PyUnstable_GetOptimizer()``
* ``PyUnstable_GetExecutor()``
* ``PyUnstable_Optimizer_NewCounter()``
* ``PyUnstable_Optimizer_NewUOpOptimizer()``

Patch by Victor Stinner.

..

.. date: 2024-05-21-19-41-41
.. gh-issue: 119344
.. nonce: QKvzQb
.. section: C API

The critical section API is now public as part of the non-limited C API.

..

.. date: 2024-05-08-21-57-50
.. gh-issue: 118789
.. nonce: Ni4UQx
.. section: C API

Add :c:func:`PyUnstable_Object_ClearWeakRefsNoCallbacks`, which clears
weakrefs without calling their callbacks.

..

.. date: 2024-04-10-16-48-04
.. gh-issue: 117511
.. nonce: RZtBRK
.. section: C API

Make the :c:type:`PyMutex` public in the non-limited C API.