.. date: 2022-06-01-17-47-40
.. gh-issue: 93418
.. nonce: 24dJuc
.. release date: 2022-06-06
.. section: Core and Builtins

Fixed an assert where an f-string has an equal sign '=' following an
expression, but there's no trailing brace. For example, f"{i=".

..

.. date: 2022-05-25-04-07-22
.. gh-issue: 91924
.. nonce: -UyO4q
.. section: Core and Builtins

Fix ``__ltrace__`` debug feature if the stdout encoding is not UTF-8. Patch
by Victor Stinner.

..

.. date: 2022-05-22-02-37-50
.. gh-issue: 93061
.. nonce: r70Imp
.. section: Core and Builtins

Backward jumps after ``async for`` loops are no longer given dubious line
numbers.

..

.. date: 2022-05-21-23-21-37
.. gh-issue: 93065
.. nonce: 5I18WC
.. section: Core and Builtins

Fix contextvars HAMT implementation to handle iteration over deep trees.

The bug was discovered and fixed by Eli Libman. See
`MagicStack/immutables#84
<https://github.com/MagicStack/immutables/issues/84>`_ for more details.

..

.. date: 2022-05-12-09-38-20
.. gh-issue: 92311
.. nonce: VEgtts
.. section: Core and Builtins

Fixed a bug where setting ``frame.f_lineno`` to jump over a list
comprehension could misbehave or crash.

..

.. date: 2022-05-01-10-58-38
.. gh-issue: 92112
.. nonce: lLJemu
.. section: Core and Builtins

Fix crash triggered by an evil custom ``mro()`` on a metaclass.

..

.. date: 2022-04-28-23-37-30
.. gh-issue: 92036
.. nonce: GZJAC9
.. section: Core and Builtins

Fix a crash in subinterpreters related to the garbage collector. When a
subinterpreter is deleted, untrack all objects tracked by its GC. To prevent
a crash in deallocator functions expecting objects to be tracked by the GC,
leak a strong reference to these objects on purpose, so they are never
deleted and their deallocator functions are not called. Patch by Victor
Stinner.

..

.. date: 2022-04-10-22-57-27
.. gh-issue: 91421
.. nonce: dHhv6U
.. section: Core and Builtins

Fix a potential integer overflow in _Py_DecodeUTF8Ex.

..

.. bpo: 47212
.. date: 2022-04-05-11-29-21
.. nonce: leF4pz
.. section: Core and Builtins

Raise :exc:`IndentationError` instead of :exc:`SyntaxError` for a bare
``except`` with no following indent. Improve :exc:`SyntaxError` locations
for an un-parenthesized generator used as arguments. Patch by Matthieu
Dartiailh.

..

.. bpo: 47182
.. date: 2022-03-31-15-37-02
.. nonce: e_4SsC
.. section: Core and Builtins

Fix a crash when using a named unicode character like ``"\N{digit nine}"``
after the main interpreter has been initialized a second time.

..

.. bpo: 46775
.. date: 2022-03-30-02-36-25
.. nonce: e3Oxqf
.. section: Core and Builtins

Some Windows system error codes(>= 10000) are now mapped into the correct
errno and may now raise a subclass of :exc:`OSError`. Patch by Dong-hee Na.

..

.. bpo: 47117
.. date: 2022-03-26-15-45-57
.. nonce: 60W6GQ
.. section: Core and Builtins

Fix a crash if we fail to decode characters in interactive mode if the
tokenizer buffers are uninitialized. Patch by Pablo Galindo.

..

.. bpo: 39829
.. date: 2022-03-11-09-39-01
.. nonce: mlW3Su
.. section: Core and Builtins

Removed the ``__len__()`` call when initializing a list and moved
initializing to ``list_extend``. Patch by Jeremiah Pascual.

..

.. bpo: 46962
.. date: 2022-03-08-21-59-57
.. nonce: UomDfz
.. section: Core and Builtins

Classes and functions that unconditionally declared their docstrings
ignoring the `--without-doc-strings` compilation flag no longer do so.

The classes affected are :class:`ctypes.UnionType`,
:class:`pickle.PickleBuffer`, :class:`testcapi.RecursingInfinitelyError`,
and :class:`types.GenericAlias`.

The functions affected are 24 methods in :mod:`ctypes`.

Patch by Oleg Iarygin.

..

.. bpo: 36819
.. date: 2021-09-28-10-58-30
.. nonce: cyV50C
.. section: Core and Builtins

Fix crashes in built-in encoders with error handlers that return position
less or equal than the starting position of non-encodable characters.

..

.. date: 2022-05-26-23-10-55
.. gh-issue: 93156
.. nonce: 4XfDVN
.. section: Library

Accessing the :attr:`pathlib.PurePath.parents` sequence of an absolute path
using negative index values produced incorrect results.

..

.. date: 2022-05-22-16-08-01
.. gh-issue: 89973
.. nonce: jc-Q4g
.. section: Library

Fix :exc:`re.error` raised in :mod:`fnmatch` if the pattern contains a
character range with upper bound lower than lower bound (e.g. ``[c-a]``).
Now such ranges are interpreted as empty ranges.

..

.. date: 2022-05-20-15-52-43
.. gh-issue: 93010
.. nonce: WF-cAc
.. section: Library

In a very special case, the email package tried to append the nonexistent
``InvalidHeaderError`` to the defect list. It should have been
``InvalidHeaderDefect``.

..

.. date: 2022-05-16-14-35-39
.. gh-issue: 92839
.. nonce: owSMyo
.. section: Library

Fixed crash resulting from calling bisect.insort() or bisect.insort_left()
with the key argument not equal to None.

..

.. date: 2022-05-11-14-34-09
.. gh-issue: 91581
.. nonce: glkou2
.. section: Library

:meth:`~datetime.datetime.utcfromtimestamp` no longer attempts to resolve
``fold`` in the pure Python implementation, since the fold is never 1 in
UTC. In addition to being slightly faster in the common case, this also
prevents some errors when the timestamp is close to :attr:`datetime.min
<datetime.datetime.min>`.  Patch by Paul Ganssle.

..

.. date: 2022-05-09-09-28-02
.. gh-issue: 92530
.. nonce: M4Q1RS
.. section: Library

Fix an issue that occurred after interrupting
:func:`threading.Condition.notify`.

..

.. date: 2022-04-30-10-53-10
.. gh-issue: 92049
.. nonce: 5SEKoh
.. section: Library

Forbid pickling constants ``re._constants.SUCCESS`` etc. Previously,
pickling did not fail, but the result could not be unpickled.

..

.. bpo: 47029
.. date: 2022-04-26-19-01-13
.. nonce: qkT42X
.. section: Library

Always close the read end of the pipe used by :class:`multiprocessing.Queue`
*after* the last write of buffered data to the write end of the pipe to
avoid :exc:`BrokenPipeError` at garbage collection and at
:meth:`multiprocessing.Queue.close` calls. Patch by Géry Ogam.

..

.. date: 2022-04-26-00-10-06
.. gh-issue: 91401
.. nonce: mddRC8
.. section: Library

Provide a fail-safe way to disable :mod:`subprocess` use of ``vfork()`` via
a private ``subprocess._USE_VFORK`` attribute. While there is currently no
known need for this, if you find a need please only set it to ``False``.
File a CPython issue as to why you needed it and link to that from a comment
in your code. This attribute is documented as a footnote in 3.11.

..

.. date: 2022-04-25-14-18-01
.. gh-issue: 91910
.. nonce: kY-JR0
.. section: Library

Add missing f prefix to f-strings in error messages from the
:mod:`multiprocessing` and :mod:`asyncio` modules.

..

.. date: 2022-04-25-10-23-01
.. gh-issue: 91810
.. nonce: DOHa6B
.. section: Library

:class:`~xml.etree.ElementTree.ElementTree` method
:meth:`~xml.etree.ElementTree.ElementTree.write` and function
:func:`~xml.etree.ElementTree.tostring` now use the text file's encoding
("UTF-8" if not available) instead of locale encoding in XML declaration
when ``encoding="unicode"`` is specified.

..

.. date: 2022-04-23-03-24-00
.. gh-issue: 91832
.. nonce: TyLi65
.. section: Library

Add ``required`` attribute to :class:`argparse.Action` repr output.

..

.. date: 2022-04-20-09-49-33
.. gh-issue: 91734
.. nonce: 4Dj4Gy
.. section: Library

Fix OSS audio support on Solaris.

..

.. date: 2022-04-19-17-30-17
.. gh-issue: 91700
.. nonce: MRJi6m
.. section: Library

Compilation of regular expression containing a conditional expression
``(?(group)...)`` now raises an appropriate :exc:`re.error` if the group
number refers to not defined group. Previously an internal RuntimeError was
raised.

..

.. date: 2022-04-19-04-33-39
.. gh-issue: 91676
.. nonce: ceQBwh
.. section: Library

Fix :class:`unittest.IsolatedAsyncioTestCase` to shutdown the per test event
loop executor before returning from its ``run`` method so that a not yet
stopped or garbage collected executor state does not persist beyond the
test.

..

.. date: 2022-04-18-16-31-33
.. gh-issue: 90568
.. nonce: 9kiU7o
.. section: Library

Parsing ``\N`` escapes of Unicode Named Character Sequences in a
:mod:`regular expression <re>` raises now :exc:`re.error` instead of
``TypeError``.

..

.. date: 2022-04-16-05-12-13
.. gh-issue: 91595
.. nonce: CocJBv
.. section: Library

Fix the comparison of character and integer inside
:func:`Tools.gdb.libpython.write_repr`. Patch by Yu Liu.

..

.. date: 2022-04-15-22-07-36
.. gh-issue: 90622
.. nonce: 0C6l8h
.. section: Library

Worker processes for :class:`concurrent.futures.ProcessPoolExecutor` are no
longer spawned on demand (a feature added in 3.9) when the multiprocessing
context start method is ``"fork"`` as that can lead to deadlocks in the
child processes due to a fork happening while threads are running.

..

.. date: 2022-04-15-18-38-21
.. gh-issue: 91575
.. nonce: fSyAxS
.. section: Library

Update case-insensitive matching in the :mod:`re` module to the latest
Unicode version.

..

.. date: 2022-04-15-13-16-25
.. gh-issue: 91581
.. nonce: 9OGsrN
.. section: Library

Remove an unhandled error case in the C implementation of calls to
:meth:`datetime.fromtimestamp <datetime.datetime.fromtimestamp>` with no
time zone (i.e. getting a local time from an epoch timestamp). This should
have no user-facing effect other than giving a possibly more accurate error
message when called with timestamps that fall on 10000-01-01 in the local
time. Patch by Paul Ganssle.

..

.. bpo: 47260
.. date: 2022-04-08-14-30-53
.. nonce: TtcNxI
.. section: Library

Fix ``os.closerange()`` potentially being a no-op in a Linux seccomp
sandbox.

..

.. bpo: 39064
.. date: 2022-04-03-19-40-09
.. nonce: 76PbIz
.. section: Library

:class:`zipfile.ZipFile` now raises :exc:`zipfile.BadZipFile` instead of
``ValueError`` when reading a corrupt zip file in which the central
directory offset is negative.

..

.. bpo: 47151
.. date: 2022-03-30-01-17-43
.. nonce: z-nQkR
.. section: Library

When subprocess tries to use vfork, it now falls back to fork if vfork
returns an error. This allows use in situations where vfork isn't allowed by
the OS kernel.

..

.. bpo: 27929
.. date: 2022-03-28-13-35-50
.. nonce: j5mAmV
.. section: Library

Fix :meth:`asyncio.loop.sock_connect` to only resolve names for
:const:`socket.AF_INET` or :const:`socket.AF_INET6` families. Resolution may
not make sense for other families, like :const:`socket.AF_BLUETOOTH` and
:const:`socket.AF_UNIX`.

..

.. bpo: 43323
.. date: 2022-03-27-12-40-16
.. nonce: 9mFPuI
.. section: Library

Fix errors in the :mod:`email` module if the charset itself contains
undecodable/unencodable characters.

..

.. bpo: 47101
.. date: 2022-03-23-15-31-02
.. nonce: rVSld-
.. section: Library

:const:`hashlib.algorithms_available` now lists only algorithms that are
provided by activated crypto providers on OpenSSL 3.0. Legacy algorithms are
not listed unless the legacy provider has been loaded into the default OSSL
context.

..

.. bpo: 46787
.. date: 2022-02-18-20-09-29
.. nonce: juwWc0
.. section: Library

Fix :class:`concurrent.futures.ProcessPoolExecutor` exception memory leak

..

.. bpo: 45393
.. date: 2022-02-09-23-44-27
.. nonce: 9v5Y8U
.. section: Library

Fix the formatting for ``await x`` and ``not x`` in the operator precedence
table when using the :func:`help` system.

..

.. bpo: 46415
.. date: 2022-01-17-16-53-30
.. nonce: 6wSYg-
.. section: Library

Fix ipaddress.ip_{address,interface,network} raising TypeError instead of
ValueError if given invalid tuple as address parameter.

..

.. bpo: 28249
.. date: 2022-01-09-14-23-00
.. nonce: 4dzB80
.. section: Library

Set :attr:`doctest.DocTest.lineno` to ``None`` when object does not have
:attr:`__doc__`.

..

.. bpo: 45138
.. date: 2021-09-08-16-21-03
.. nonce: yghUrK
.. section: Library

Fix a regression in the :mod:`sqlite3` trace callback where bound parameters
were not expanded in the passed statement string. The regression was
introduced in Python 3.10 by :issue:`40318`. Patch by Erlend E. Aasland.

..

.. bpo: 44493
.. date: 2021-07-26-10-46-49
.. nonce: xp3CRH
.. section: Library

Add missing terminated NUL in sockaddr_un's length

This was potentially observable when using non-abstract AF_UNIX datagram
sockets to processes written in another programming language.

..

.. bpo: 42627
.. date: 2021-05-22-07-58-59
.. nonce: EejtD0
.. section: Library

Fix incorrect parsing of Windows registry proxy settings

..

.. bpo: 36073
.. date: 2019-06-22-11-01-45
.. nonce: ED8mB9
.. section: Library

Raise :exc:`~sqlite3.ProgrammingError` instead of segfaulting on recursive
usage of cursors in :mod:`sqlite3` converters. Patch by Sergey Fedoseev.

..

.. date: 2022-05-26-11-33-23
.. gh-issue: 86438
.. nonce: kEGGmK
.. section: Documentation

Clarify that :option:`-W` and :envvar:`PYTHONWARNINGS` are matched literally
and case-insensitively, rather than as regular expressions, in
:mod:`warnings`.

..

.. date: 2022-05-18-23-58-26
.. gh-issue: 92240
.. nonce: bHvYiz
.. section: Documentation

Added release dates for "What's New in Python 3.X" for 3.0, 3.1, 3.2, 3.8
and 3.10

..

.. date: 2022-04-24-22-09-31
.. gh-issue: 91888
.. nonce: kTjJLx
.. section: Documentation

Add a new ``gh`` role to the documentation to link to GitHub issues.

..

.. date: 2022-04-23-00-22-54
.. gh-issue: 91783
.. nonce: N09dRR
.. section: Documentation

Document security issues concerning the use of the function
:meth:`shutil.unpack_archive`

..

.. date: 2022-04-19-20-16-00
.. gh-issue: 91547
.. nonce: LsNWER
.. section: Documentation

Remove "Undocumented modules" page.

..

.. bpo: 44347
.. date: 2022-04-10-20-28-20
.. nonce: Q1m3DM
.. section: Documentation

Clarify the meaning of *dirs_exist_ok*, a kwarg of :func:`shutil.copytree`.

..

.. bpo: 38668
.. date: 2022-04-01-09-28-31
.. nonce: j4mrqW
.. section: Documentation

Update the introduction to documentation for :mod:`os.path` to remove
warnings that became irrelevant after the implementations of :pep:`383` and
:pep:`529`.

..

.. bpo: 47138
.. date: 2022-03-28-12-29-42
.. nonce: 2B4N-k
.. section: Documentation

Pin Jinja to a version compatible with Sphinx version 3.2.1.

..

.. bpo: 46962
.. date: 2022-03-08-22-10-38
.. nonce: FIVe9I
.. section: Documentation

All docstrings in code snippets are now wrapped into :func:`PyDoc_STR` to
follow the guideline of `PEP 7's Documentation Strings paragraph
<https://www.python.org/dev/peps/pep-0007/#documentation-strings>`_. Patch
by Oleg Iarygin.

..

.. bpo: 26792
.. date: 2022-01-23-20-44-53
.. nonce: dQ1v1W
.. section: Documentation

Improve the docstrings of :func:`runpy.run_module` and
:func:`runpy.run_path`. Original patch by Andrew Brezovsky.

..

.. bpo: 40838
.. date: 2022-01-13-16-03-15
.. nonce: k3NVCf
.. section: Documentation

Document that :func:`inspect.getdoc`, :func:`inspect.getmodule`, and
:func:`inspect.getsourcefile` might return ``None``.

..

.. bpo: 45790
.. date: 2021-11-12-11-03-55
.. nonce: 6yuhe8
.. section: Documentation

Adjust inaccurate phrasing in :doc:`../extending/newtypes_tutorial` about
the ``ob_base`` field and the macros used to access its contents.

..

.. bpo: 42340
.. date: 2020-11-12-21-26-31
.. nonce: apumUL
.. section: Documentation

Document that in some circumstances :exc:`KeyboardInterrupt` may cause the
code to enter an inconsistent state. Provided a sample workaround to avoid
it if needed.

..

.. bpo: 41233
.. date: 2020-07-07-22-54-51
.. nonce: lyUJ8L
.. section: Documentation

Link the errnos referenced in ``Doc/library/exceptions.rst`` to their
respective section in ``Doc/library/errno.rst``, and vice versa. Previously
this was only done for EINTR and InterruptedError. Patch by Yan "yyyyyyyan"
Orestes.

..

.. bpo: 38056
.. date: 2019-09-12-08-28-17
.. nonce: 6ktYkc
.. section: Documentation

Overhaul the :ref:`error-handlers` documentation in :mod:`codecs`.

..

.. bpo: 13553
.. date: 2017-12-10-19-13-39
.. nonce: gQbZs4
.. section: Documentation

Document tkinter.Tk args.

..

.. date: 2022-05-25-23-07-15
.. gh-issue: 92886
.. nonce: Aki63_
.. section: Tests

Fixing tests that fail when running with optimizations (``-O``) in
``test_imaplib.py``.

..

.. date: 2022-05-12-05-51-06
.. gh-issue: 92670
.. nonce: 7L43Z_
.. section: Tests

Skip ``test_shutil.TestCopy.test_copyfile_nonexistent_dir`` test on AIX as
the test uses a trailing slash to force the OS consider the path as a
directory, but on AIX the trailing slash has no effect and is considered as
a file.

..

.. date: 2022-04-25-11-16-36
.. gh-issue: 91904
.. nonce: 13Uvrz
.. section: Tests

Fix initialization of :envvar:`PYTHONREGRTEST_UNICODE_GUARD` which prevented
running regression tests on non-UTF-8 locale.

..

.. date: 2022-04-16-17-54-05
.. gh-issue: 91607
.. nonce: FnXjtW
.. section: Tests

Fix ``test_concurrent_futures`` to test the correct multiprocessing start
method context in several cases where the test logic mixed this up.

..

.. bpo: 47205
.. date: 2022-04-03-14-38-21
.. nonce: hbbTnh
.. section: Tests

Skip test for :func:`~os.sched_getaffinity` and
:func:`~os.sched_setaffinity` error case on FreeBSD.

..

.. bpo: 47104
.. date: 2022-03-23-22-45-51
.. nonce: _esUq8
.. section: Tests

Rewrite :func:`asyncio.to_thread` tests to use
:class:`unittest.IsolatedAsyncioTestCase`.

..

.. bpo: 29890
.. date: 2022-01-24-21-31-09
.. nonce: zEG-ra
.. section: Tests

Add tests for :class:`ipaddress.IPv4Interface` and
:class:`ipaddress.IPv6Interface` construction with tuple arguments. Original
patch and tests by louisom.

..

.. bpo: 47103
.. date: 2022-03-23-20-01-16
.. nonce: b4-00F
.. section: Build

Windows ``PGInstrument`` builds now copy a required DLL into the output
directory, making it easier to run the profile stage of a PGO build.

..

.. date: 2022-05-19-14-01-30
.. gh-issue: 92984
.. nonce: Dsxnlr
.. section: Windows

Explicitly disable incremental linking for non-Debug builds

..

.. bpo: 47194
.. date: 2022-04-01-14-57-40
.. nonce: IB0XL4
.. section: Windows

Update ``zlib`` to v1.2.12 to resolve CVE-2018-25032.

..

.. bpo: 46785
.. date: 2022-03-13-20-35-41
.. nonce: Pnknyl
.. section: Windows

Fix race condition between :func:`os.stat` and unlinking a file on Windows,
by using errors codes returned by ``FindFirstFileW()`` when appropriate in
``win32_xstat_impl``.

..

.. bpo: 40859
.. date: 2020-06-04-10-42-04
.. nonce: isKSw7
.. section: Windows

Update Windows build to use xz-5.2.5

..

.. date: 2022-04-20-14-26-14
.. gh-issue: 91583
.. nonce: 200qI0
.. section: Tools/Demos

Fix regression in the code generated by Argument Clinic for functions with
the ``defining_class`` parameter.