mirror of https://github.com/python/cpython
566 lines
17 KiB
ReStructuredText
566 lines
17 KiB
ReStructuredText
|
|
****************************
|
|
What's New In Python 3.14
|
|
****************************
|
|
|
|
:Editor: TBD
|
|
|
|
.. Rules for maintenance:
|
|
|
|
* Anyone can add text to this document. Do not spend very much time
|
|
on the wording of your changes, because your text will probably
|
|
get rewritten to some degree.
|
|
|
|
* The maintainer will go through Misc/NEWS periodically and add
|
|
changes; it's therefore more important to add your changes to
|
|
Misc/NEWS than to this file.
|
|
|
|
* This is not a complete list of every single change; completeness
|
|
is the purpose of Misc/NEWS. Some changes I consider too small
|
|
or esoteric to include. If such a change is added to the text,
|
|
I'll just remove it. (This is another reason you shouldn't spend
|
|
too much time on writing your addition.)
|
|
|
|
* If you want to draw your new text to the attention of the
|
|
maintainer, add 'XXX' to the beginning of the paragraph or
|
|
section.
|
|
|
|
* It's OK to just add a fragmentary note about a change. For
|
|
example: "XXX Describe the transmogrify() function added to the
|
|
socket module." The maintainer will research the change and
|
|
write the necessary text.
|
|
|
|
* You can comment out your additions if you like, but it's not
|
|
necessary (especially when a final release is some months away).
|
|
|
|
* Credit the author of a patch or bugfix. Just the name is
|
|
sufficient; the e-mail address isn't necessary.
|
|
|
|
* It's helpful to add the issue number as a comment:
|
|
|
|
XXX Describe the transmogrify() function added to the socket
|
|
module.
|
|
(Contributed by P.Y. Developer in :gh:`12345`.)
|
|
|
|
This saves the maintainer the effort of going through the VCS log
|
|
when researching a change.
|
|
|
|
This article explains the new features in Python 3.14, compared to 3.13.
|
|
|
|
For full details, see the :ref:`changelog <changelog>`.
|
|
|
|
.. note::
|
|
|
|
Prerelease users should be aware that this document is currently in draft
|
|
form. It will be updated substantially as Python 3.14 moves towards release,
|
|
so it's worth checking back even after reading earlier versions.
|
|
|
|
|
|
Summary -- Release highlights
|
|
=============================
|
|
|
|
.. This section singles out the most important changes in Python 3.14.
|
|
Brevity is key.
|
|
|
|
|
|
.. PEP-sized items next.
|
|
|
|
|
|
|
|
New Features
|
|
============
|
|
|
|
|
|
|
|
Other Language Changes
|
|
======================
|
|
|
|
* Incorrect usage of :keyword:`await` and asynchronous comprehensions
|
|
is now detected even if the code is optimized away by the :option:`-O`
|
|
command line option. For example, ``python -O -c 'assert await 1'``
|
|
now produces a :exc:`SyntaxError`. (Contributed by Jelle Zijlstra in :gh:`121637`.)
|
|
|
|
* Writes to ``__debug__`` are now detected even if the code is optimized
|
|
away by the :option:`-O` command line option. For example,
|
|
``python -O -c 'assert (__debug__ := 1)'`` now produces a
|
|
:exc:`SyntaxError`. (Contributed by Irit Katriel in :gh:`122245`.)
|
|
|
|
* Added class methods :meth:`float.from_number` and :meth:`complex.from_number`
|
|
to convert a number to :class:`float` or :class:`complex` type correspondingly.
|
|
They raise an error if the argument is a string.
|
|
(Contributed by Serhiy Storchaka in :gh:`84978`.)
|
|
|
|
|
|
New Modules
|
|
===========
|
|
|
|
* None yet.
|
|
|
|
|
|
Improved Modules
|
|
================
|
|
|
|
|
|
ast
|
|
---
|
|
|
|
* Added :func:`ast.compare` for comparing two ASTs.
|
|
(Contributed by Batuhan Taskaya and Jeremy Hylton in :issue:`15987`.)
|
|
|
|
* Add support for :func:`copy.replace` for AST nodes.
|
|
|
|
(Contributed by Bénédikt Tran in :gh:`121141`.)
|
|
|
|
|
|
ctypes
|
|
------
|
|
|
|
* The layout of :ref:`bit fields <ctypes-bit-fields-in-structures-unions>`
|
|
in :class:`~ctypes.Structure` and :class:`~ctypes.Union`
|
|
now matches platform defaults (GCC/Clang or MVSC) more closely.
|
|
In particular, fields no longer overlap.
|
|
(Contributed by Matthias Görgens in :gh:`97702`.)
|
|
|
|
* The :attr:`.Structure._layout_` class attribute can now be set
|
|
to help match a non-default ABI.
|
|
(Contributed by Petr Viktorin in :gh:`97702`.)
|
|
|
|
|
|
dis
|
|
---
|
|
|
|
* Added support for rendering full source location information of
|
|
:class:`instructions <dis.Instruction>`, rather than only the line number.
|
|
This feature is added to the following interfaces via the ``show_positions``
|
|
keyword argument:
|
|
|
|
- :class:`dis.Bytecode`,
|
|
- :func:`dis.dis`, :func:`dis.distb`, and
|
|
- :func:`dis.disassemble`.
|
|
|
|
This feature is also exposed via :option:`dis --show-positions`.
|
|
|
|
(Contributed by Bénédikt Tran in :gh:`123165`.)
|
|
|
|
|
|
fractions
|
|
---------
|
|
|
|
Added support for converting any objects that have the
|
|
:meth:`!as_integer_ratio` method to a :class:`~fractions.Fraction`.
|
|
(Contributed by Serhiy Storchaka in :gh:`82017`.)
|
|
|
|
|
|
http
|
|
----
|
|
|
|
Directory lists and error pages generated by the :mod:`http.server`
|
|
module allow the browser to apply its default dark mode.
|
|
(Contributed by Yorik Hansen in :gh:`123430`.)
|
|
|
|
|
|
json
|
|
----
|
|
|
|
Add notes for JSON serialization errors that allow to identify the source
|
|
of the error.
|
|
(Contributed by Serhiy Storchaka in :gh:`122163`.)
|
|
|
|
Enable :mod:`json` module to work as a script using the :option:`-m` switch: ``python -m json``.
|
|
See the :ref:`JSON command-line interface <json-commandline>` documentation.
|
|
(Contributed by Trey Hunner in :gh:`122873`.)
|
|
|
|
|
|
operator
|
|
--------
|
|
|
|
* Two new functions ``operator.is_none`` and ``operator.is_not_none``
|
|
have been added, such that ``operator.is_none(obj)`` is equivalent
|
|
to ``obj is None`` and ``operator.is_not_none(obj)`` is equivalent
|
|
to ``obj is not None``.
|
|
(Contributed by Raymond Hettinger and Nico Mexis in :gh:`115808`.)
|
|
|
|
|
|
os
|
|
--
|
|
|
|
* Added the :data:`os.environ.refresh() <os.environ>` method to update
|
|
:data:`os.environ` with changes to the environment made by :func:`os.putenv`,
|
|
by :func:`os.unsetenv`, or made outside Python in the same process.
|
|
(Contributed by Victor Stinner in :gh:`120057`.)
|
|
|
|
|
|
pathlib
|
|
-------
|
|
|
|
* Add methods to :class:`pathlib.Path` to recursively copy or move files and
|
|
directories:
|
|
|
|
* :meth:`~pathlib.Path.copy` copies a file or directory tree to a destination.
|
|
* :meth:`~pathlib.Path.copy_into` copies *into* a destination directory.
|
|
* :meth:`~pathlib.Path.move` moves a file or directory tree to a destination.
|
|
* :meth:`~pathlib.Path.move_into` moves *into* a destination directory.
|
|
|
|
(Contributed by Barney Gale in :gh:`73991`.)
|
|
|
|
|
|
pdb
|
|
---
|
|
|
|
* Hard-coded breakpoints (:func:`breakpoint` and :func:`pdb.set_trace`) now
|
|
reuse the most recent :class:`~pdb.Pdb` instance that calls
|
|
:meth:`~pdb.Pdb.set_trace`, instead of creating a new one each time.
|
|
As a result, all the instance specific data like :pdbcmd:`display` and
|
|
:pdbcmd:`commands` are preserved across hard-coded breakpoints.
|
|
(Contributed by Tian Gao in :gh:`121450`.)
|
|
|
|
|
|
pickle
|
|
------
|
|
|
|
* Set the default protocol version on the :mod:`pickle` module to 5.
|
|
For more details, please see :ref:`pickle protocols <pickle-protocols>`.
|
|
|
|
|
|
symtable
|
|
--------
|
|
|
|
* Expose the following :class:`symtable.Symbol` methods:
|
|
|
|
* :meth:`~symtable.Symbol.is_free_class`
|
|
* :meth:`~symtable.Symbol.is_comp_iter`
|
|
* :meth:`~symtable.Symbol.is_comp_cell`
|
|
|
|
(Contributed by Bénédikt Tran in :gh:`120029`.)
|
|
|
|
.. Add improved modules above alphabetically, not here at the end.
|
|
|
|
Optimizations
|
|
=============
|
|
|
|
asyncio
|
|
-------
|
|
|
|
* :mod:`asyncio` now uses double linked list implementation for native tasks
|
|
which speeds up execution by 10% on standard pyperformance benchmarks and
|
|
reduces memory usage.
|
|
(Contributed by Kumar Aditya in :gh:`107803`.)
|
|
|
|
Deprecated
|
|
==========
|
|
|
|
* :mod:`builtins`:
|
|
Passing a complex number as the *real* or *imag* argument in the
|
|
:func:`complex` constructor is now deprecated; it should only be passed
|
|
as a single positional argument.
|
|
(Contributed by Serhiy Storchaka in :gh:`109218`.)
|
|
|
|
* :mod:`os`:
|
|
:term:`Soft deprecate <soft deprecated>` :func:`os.popen` and
|
|
:func:`os.spawn* <os.spawnl>` functions. They should no longer be used to
|
|
write new code. The :mod:`subprocess` module is recommended instead.
|
|
(Contributed by Victor Stinner in :gh:`120743`.)
|
|
|
|
* :mod:`symtable`:
|
|
Deprecate :meth:`symtable.Class.get_methods` due to the lack of interest.
|
|
(Contributed by Bénédikt Tran in :gh:`119698`.)
|
|
|
|
.. Add deprecations above alphabetically, not here at the end.
|
|
|
|
.. include:: ../deprecations/pending-removal-in-3.15.rst
|
|
|
|
.. include:: ../deprecations/pending-removal-in-3.16.rst
|
|
|
|
.. include:: ../deprecations/pending-removal-in-future.rst
|
|
|
|
Removed
|
|
=======
|
|
|
|
argparse
|
|
--------
|
|
|
|
* Remove the *type*, *choices*, and *metavar* parameters
|
|
of :class:`!argparse.BooleanOptionalAction`.
|
|
They were deprecated since 3.12.
|
|
|
|
ast
|
|
---
|
|
|
|
* Remove the following classes. They were all deprecated since Python 3.8,
|
|
and have emitted deprecation warnings since Python 3.12:
|
|
|
|
* :class:`!ast.Num`
|
|
* :class:`!ast.Str`
|
|
* :class:`!ast.Bytes`
|
|
* :class:`!ast.NameConstant`
|
|
* :class:`!ast.Ellipsis`
|
|
|
|
Use :class:`ast.Constant` instead. As a consequence of these removals,
|
|
user-defined ``visit_Num``, ``visit_Str``, ``visit_Bytes``,
|
|
``visit_NameConstant`` and ``visit_Ellipsis`` methods on custom
|
|
:class:`ast.NodeVisitor` subclasses will no longer be called when the
|
|
``NodeVisitor`` subclass is visiting an AST. Define a ``visit_Constant``
|
|
method instead.
|
|
|
|
Also, remove the following deprecated properties on :class:`ast.Constant`,
|
|
which were present for compatibility with the now-removed AST classes:
|
|
|
|
* :attr:`!ast.Constant.n`
|
|
* :attr:`!ast.Constant.s`
|
|
|
|
Use :attr:`!ast.Constant.value` instead.
|
|
|
|
(Contributed by Alex Waygood in :gh:`119562`.)
|
|
|
|
asyncio
|
|
-------
|
|
|
|
* Remove the following classes and functions. They were all deprecated and
|
|
emitted deprecation warnings since Python 3.12:
|
|
|
|
* :class:`!asyncio.AbstractChildWatcher`
|
|
* :class:`!asyncio.SafeChildWatcher`
|
|
* :class:`!asyncio.MultiLoopChildWatcher`
|
|
* :class:`!asyncio.FastChildWatcher`
|
|
* :class:`!asyncio.ThreadedChildWatcher`
|
|
* :class:`!asyncio.PidfdChildWatcher`
|
|
* :meth:`!asyncio.AbstractEventLoopPolicy.get_child_watcher`
|
|
* :meth:`!asyncio.AbstractEventLoopPolicy.set_child_watcher`
|
|
* :func:`!asyncio.get_child_watcher`
|
|
* :func:`!asyncio.set_child_watcher`
|
|
|
|
(Contributed by Kumar Aditya in :gh:`120804`.)
|
|
|
|
collections.abc
|
|
---------------
|
|
|
|
* Remove :class:`!collections.abc.ByteString`. It had previously raised a
|
|
:exc:`DeprecationWarning` since Python 3.12.
|
|
|
|
email
|
|
-----
|
|
|
|
* Remove the *isdst* parameter from :func:`email.utils.localtime`.
|
|
(Contributed by Hugo van Kemenade in :gh:`118798`.)
|
|
|
|
importlib
|
|
---------
|
|
|
|
* Remove deprecated :mod:`importlib.abc` classes:
|
|
|
|
* :class:`!importlib.abc.ResourceReader`
|
|
* :class:`!importlib.abc.Traversable`
|
|
* :class:`!importlib.abc.TraversableResources`
|
|
|
|
Use :mod:`importlib.resources.abc` classes instead:
|
|
|
|
* :class:`importlib.resources.abc.Traversable`
|
|
* :class:`importlib.resources.abc.TraversableResources`
|
|
|
|
(Contributed by Jason R. Coombs and Hugo van Kemenade in :gh:`93963`.)
|
|
|
|
itertools
|
|
---------
|
|
|
|
* Remove :mod:`itertools` support for copy, deepcopy, and pickle operations.
|
|
These had previously raised a :exc:`DeprecationWarning` since Python 3.12.
|
|
(Contributed by Raymond Hettinger in :gh:`101588`.)
|
|
|
|
pathlib
|
|
-------
|
|
|
|
* Remove support for passing additional keyword arguments to
|
|
:class:`pathlib.Path`. In previous versions, any such arguments are ignored.
|
|
* Remove support for passing additional positional arguments to
|
|
:meth:`pathlib.PurePath.relative_to` and
|
|
:meth:`~pathlib.PurePath.is_relative_to`. In previous versions, any such
|
|
arguments are joined onto *other*.
|
|
|
|
pty
|
|
---
|
|
|
|
* Remove deprecated :func:`!pty.master_open` and :func:`!pty.slave_open`.
|
|
They had previously raised a :exc:`DeprecationWarning` since Python 3.12.
|
|
Use :func:`pty.openpty` instead.
|
|
(Contributed by Nikita Sobolev in :gh:`118824`.)
|
|
|
|
sqlite3
|
|
-------
|
|
|
|
* Remove :data:`!version` and :data:`!version_info` from :mod:`sqlite3`.
|
|
(Contributed by Hugo van Kemenade in :gh:`118924`.)
|
|
|
|
* Disallow using a sequence of parameters with named placeholders.
|
|
This had previously raised a :exc:`DeprecationWarning` since Python 3.12;
|
|
it will now raise a :exc:`sqlite3.ProgrammingError`.
|
|
(Contributed by Erlend E. Aasland in :gh:`118928` and :gh:`101693`.)
|
|
|
|
typing
|
|
------
|
|
|
|
* Remove :class:`!typing.ByteString`. It had previously raised a
|
|
:exc:`DeprecationWarning` since Python 3.12.
|
|
|
|
urllib
|
|
------
|
|
|
|
* Remove deprecated :class:`!Quoter` class from :mod:`urllib.parse`.
|
|
It had previously raised a :exc:`DeprecationWarning` since Python 3.11.
|
|
(Contributed by Nikita Sobolev in :gh:`118827`.)
|
|
|
|
Others
|
|
------
|
|
|
|
* Using :data:`NotImplemented` in a boolean context will now raise a :exc:`TypeError`.
|
|
It had previously raised a :exc:`DeprecationWarning` since Python 3.9. (Contributed
|
|
by Jelle Zijlstra in :gh:`118767`.)
|
|
|
|
* The :func:`int` built-in no longer delegates to
|
|
:meth:`~object.__trunc__`. Classes that want to support conversion to
|
|
integer must implement either :meth:`~object.__int__` or
|
|
:meth:`~object.__index__`. (Contributed by Mark Dickinson in :gh:`119743`.)
|
|
|
|
|
|
Porting to Python 3.14
|
|
======================
|
|
|
|
This section lists previously described changes and other bugfixes
|
|
that may require changes to your code.
|
|
|
|
Changes in the Python API
|
|
-------------------------
|
|
|
|
* :class:`functools.partial` is now a method descriptor.
|
|
Wrap it in :func:`staticmethod` if you want to preserve the old behavior.
|
|
(Contributed by Serhiy Storchaka and Dominykas Grigonis in :gh:`121027`.)
|
|
|
|
Build Changes
|
|
=============
|
|
|
|
|
|
C API Changes
|
|
=============
|
|
|
|
New Features
|
|
------------
|
|
|
|
* Add :c:func:`PyLong_GetSign` function to get the sign of :class:`int` objects.
|
|
(Contributed by Sergey B Kirpichev in :gh:`116560`.)
|
|
|
|
* Add a new :c:type:`PyUnicodeWriter` API to create a Python :class:`str`
|
|
object:
|
|
|
|
* :c:func:`PyUnicodeWriter_Create`.
|
|
* :c:func:`PyUnicodeWriter_Discard`.
|
|
* :c:func:`PyUnicodeWriter_Finish`.
|
|
* :c:func:`PyUnicodeWriter_WriteChar`.
|
|
* :c:func:`PyUnicodeWriter_WriteUTF8`.
|
|
* :c:func:`PyUnicodeWriter_WriteUCS4`.
|
|
* :c:func:`PyUnicodeWriter_WriteWideChar`.
|
|
* :c:func:`PyUnicodeWriter_WriteStr`.
|
|
* :c:func:`PyUnicodeWriter_WriteRepr`.
|
|
* :c:func:`PyUnicodeWriter_WriteSubstring`.
|
|
* :c:func:`PyUnicodeWriter_Format`.
|
|
* :c:func:`PyUnicodeWriter_DecodeUTF8Stateful`.
|
|
|
|
(Contributed by Victor Stinner in :gh:`119182`.)
|
|
|
|
* Add :c:func:`PyIter_NextItem` to replace :c:func:`PyIter_Next`,
|
|
which has an ambiguous return value.
|
|
(Contributed by Irit Katriel and Erlend Aasland in :gh:`105201`.)
|
|
|
|
* :c:func:`Py_Finalize` now deletes all interned strings. This
|
|
is backwards incompatible to any C-Extension that holds onto an interned
|
|
string after a call to :c:func:`Py_Finalize` and is then reused after a
|
|
call to :c:func:`Py_Initialize`. Any issues arising from this behavior will
|
|
normally result in crashes during the exectuion of the subsequent call to
|
|
:c:func:`Py_Initialize` from accessing uninitialized memory. To fix, use
|
|
an address sanitizer to identify any use-after-free coming from
|
|
an interned string and deallocate it during module shutdown.
|
|
(Contribued by Eddie Elizondo in :gh:`113601`.)
|
|
|
|
* Add new functions to convert C ``<stdint.h>`` numbers from/to Python
|
|
:class:`int`:
|
|
|
|
* :c:func:`PyLong_FromInt32`
|
|
* :c:func:`PyLong_FromInt64`
|
|
* :c:func:`PyLong_FromUInt32`
|
|
* :c:func:`PyLong_FromUInt64`
|
|
* :c:func:`PyLong_AsInt32`
|
|
* :c:func:`PyLong_AsInt64`
|
|
* :c:func:`PyLong_AsUInt32`
|
|
* :c:func:`PyLong_AsUInt64`
|
|
|
|
(Contributed by Victor Stinner in :gh:`120389`.)
|
|
|
|
* Add :c:func:`PyBytes_Join(sep, iterable) <PyBytes_Join>` function,
|
|
similar to ``sep.join(iterable)`` in Python.
|
|
(Contributed by Victor Stinner in :gh:`121645`.)
|
|
|
|
* Add :c:func:`Py_HashBuffer` to compute and return the hash value of a buffer.
|
|
(Contributed by Antoine Pitrou and Victor Stinner in :gh:`122854`.)
|
|
|
|
* Add functions to get and set the current runtime Python configuration
|
|
(:pep:`741`):
|
|
|
|
* :c:func:`PyConfig_Get`
|
|
* :c:func:`PyConfig_GetInt`
|
|
* :c:func:`PyConfig_Set`
|
|
* :c:func:`PyConfig_Names`
|
|
|
|
(Contributed by Victor Stinner in :gh:`107954`.)
|
|
|
|
* Add functions to configure the Python initialization (:pep:`741`):
|
|
|
|
* :c:func:`PyInitConfig_Create`
|
|
* :c:func:`PyInitConfig_Free`
|
|
* :c:func:`PyInitConfig_GetError`
|
|
* :c:func:`PyInitConfig_GetExitCode`
|
|
* :c:func:`PyInitConfig_HasOption`
|
|
* :c:func:`PyInitConfig_GetInt`
|
|
* :c:func:`PyInitConfig_GetStr`
|
|
* :c:func:`PyInitConfig_GetStrList`
|
|
* :c:func:`PyInitConfig_FreeStrList`
|
|
* :c:func:`PyInitConfig_SetInt`
|
|
* :c:func:`PyInitConfig_SetStr`
|
|
* :c:func:`PyInitConfig_SetStrList`
|
|
* :c:func:`PyInitConfig_AddModule`
|
|
* :c:func:`Py_InitializeFromInitConfig`
|
|
|
|
(Contributed by Victor Stinner in :gh:`107954`.)
|
|
|
|
|
|
Porting to Python 3.14
|
|
----------------------
|
|
|
|
* In the limited C API 3.14 and newer, :c:func:`Py_TYPE` is now implemented as
|
|
an opaque function call to hide implementation details.
|
|
(Contributed by Victor Stinner in :gh:`120600`.)
|
|
|
|
|
|
Deprecated
|
|
----------
|
|
|
|
* Macros :c:macro:`!Py_IS_NAN`, :c:macro:`!Py_IS_INFINITY`
|
|
and :c:macro:`!Py_IS_FINITE` are :term:`soft deprecated`,
|
|
use instead :c:macro:`!isnan`, :c:macro:`!isinf` and
|
|
:c:macro:`!isfinite` available from :file:`math.h`
|
|
since C99. (Contributed by Sergey B Kirpichev in :gh:`119613`.)
|
|
|
|
* :func:`!asyncio.iscoroutinefunction` is deprecated
|
|
and will be removed in Python 3.16,
|
|
use :func:`inspect.iscoroutinefunction` instead.
|
|
(Contributed by Jiahao Li and Kumar Aditya in :gh:`122875`.)
|
|
|
|
.. Add deprecations above alphabetically, not here at the end.
|
|
|
|
.. include:: ../deprecations/c-api-pending-removal-in-3.15.rst
|
|
|
|
.. include:: ../deprecations/c-api-pending-removal-in-future.rst
|
|
|
|
Removed
|
|
-------
|
|
|
|
* Creating :c:data:`immutable types <Py_TPFLAGS_IMMUTABLETYPE>` with mutable
|
|
bases was deprecated since 3.12 and now raises a :exc:`TypeError`.
|