mirror of https://github.com/python/cpython
427 lines
13 KiB
ReStructuredText
427 lines
13 KiB
ReStructuredText
****************************
|
|
What's New In Python 3.5
|
|
****************************
|
|
|
|
:Release: |release|
|
|
:Date: |today|
|
|
|
|
.. 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 bug/patch number as a comment:
|
|
|
|
XXX Describe the transmogrify() function added to the socket
|
|
module.
|
|
(Contributed by P.Y. Developer in :issue:`12345`.)
|
|
|
|
This saves the maintainer the effort of going through the Mercurial log
|
|
when researching a change.
|
|
|
|
This article explains the new features in Python 3.5, compared to 3.4.
|
|
|
|
For full details, see the :source:`Misc/NEWS` file.
|
|
|
|
.. note:: Prerelease users should be aware that this document is currently in
|
|
draft form. It will be updated substantially as Python 3.5 moves towards
|
|
release, so it's worth checking back even after reading earlier versions.
|
|
|
|
|
|
.. seealso::
|
|
|
|
:pep:`478` - Python 3.5 Release Schedule
|
|
|
|
|
|
Summary -- Release highlights
|
|
=============================
|
|
|
|
.. This section singles out the most important changes in Python 3.3.
|
|
Brevity is key.
|
|
|
|
New syntax features:
|
|
|
|
* None yet.
|
|
|
|
New library modules:
|
|
|
|
* None yet.
|
|
|
|
New built-in features:
|
|
|
|
* None yet.
|
|
|
|
Implementation improvements:
|
|
|
|
* When the ``LC_TYPE`` locale is the POSIX locale (``C`` locale),
|
|
:py:data:`sys.stdin` and :py:data:`sys.stdout` are now using the
|
|
``surrogateescape`` error handler, instead of the ``strict`` error handler
|
|
(:issue:`19977`).
|
|
|
|
Significantly Improved Library Modules:
|
|
|
|
* None yet.
|
|
|
|
Security improvements:
|
|
|
|
* None yet.
|
|
|
|
Please read on for a comprehensive list of user-facing changes.
|
|
|
|
|
|
.. PEP-sized items next.
|
|
|
|
.. _pep-4XX:
|
|
|
|
.. PEP 4XX: Virtual Environments
|
|
.. =============================
|
|
|
|
|
|
.. (Implemented by Foo Bar.)
|
|
|
|
.. .. seealso::
|
|
|
|
:pep:`4XX` - Python Virtual Environments
|
|
PEP written by Carl Meyer
|
|
|
|
|
|
|
|
|
|
Other Language Changes
|
|
======================
|
|
|
|
Some smaller changes made to the core Python language are:
|
|
|
|
* None yet.
|
|
|
|
|
|
|
|
New Modules
|
|
===========
|
|
|
|
.. module name
|
|
.. -----------
|
|
|
|
* None yet.
|
|
|
|
|
|
Improved Modules
|
|
================
|
|
|
|
code
|
|
----
|
|
|
|
* The :func:`code.InteractiveInterpreter.showtraceback` method now prints
|
|
the full chained traceback, just like the interactive interpreter.
|
|
(Contributed by Claudiu.Popa in :issue:`17442`.)
|
|
|
|
compileall
|
|
----------
|
|
|
|
* :func:`compileall.compile_dir` and :mod:`compileall`'s command-line interface
|
|
can now do parallel bytecode compilation.
|
|
(Contributed by Claudiu Popa in :issue:`16104`.)
|
|
|
|
doctest
|
|
-------
|
|
|
|
* :func:`doctest.DocTestSuite` returns an empty :class:`unittest.TestSuite` if
|
|
*module* contains no docstrings instead of raising :exc:`ValueError`.
|
|
(Contributed by Glenn Jones in :issue:`15916`.)
|
|
|
|
glob
|
|
----
|
|
|
|
* :func:`~glob.iglob` and :func:`~glob.glob` now support recursive search in
|
|
subdirectories using the "``**``" pattern.
|
|
(Contributed by Serhiy Storchaka in :issue:`13968`.)
|
|
|
|
imaplib
|
|
-------
|
|
|
|
* :class:`IMAP4` now supports the context management protocol. When used in a
|
|
:keyword:`with` statement, the IMAP4 ``LOGOUT`` command will be called
|
|
automatically at the end of the block. (Contributed by Tarek Ziadé and
|
|
Serhiy Storchaka in :issue:`4972`.)
|
|
|
|
imghdr
|
|
------
|
|
|
|
* :func:`~imghdr.what` now recognizes the `OpenEXR <http://www.openexr.com>`_
|
|
format. (Contributed by Martin vignali and Cladui Popa in :issue:`20295`.)
|
|
|
|
importlib
|
|
---------
|
|
|
|
* :class:`importlib.util.LazyLoader` allows for the lazy loading of modules in
|
|
applications where startup time is paramount.
|
|
(Contributed by Brett Cannon in :issue:`17621`.)
|
|
|
|
* :func:`importlib.abc.InspectLoader.source_to_code` is now a
|
|
static method to make it easier to work with source code in a string.
|
|
With a module object that you want to initialize you can then use
|
|
``exec(code, module.__dict__)`` to execute the code in the module.
|
|
|
|
* :func:`importlib.util.module_from_spec` is now the preferred way to create a
|
|
new module. Compared to :class:`types.ModuleType`, this new function will set
|
|
the various import-controlled attributes based on the passed-in spec object.
|
|
|
|
inspect
|
|
-------
|
|
|
|
* :class:`inspect.Signature` and :class:`inspect.Parameter` are now
|
|
picklable and hashable. (Contributed by Yury Selivanov in :issue:`20726`
|
|
and :issue:`20334`.)
|
|
|
|
* New class method :meth:`inspect.Signature.from_callable`, which makes
|
|
subclassing of :class:`~inspect.Signature` easier. (Contributed
|
|
by Yury Selivanov and Eric Snow in :issue:`17373`.)
|
|
|
|
ipaddress
|
|
---------
|
|
|
|
* :class:`ipaddress.IPv4Network` and :class:`ipaddress.IPv6Network` now
|
|
accept an ``(address, netmask)`` tuple argument, so as to easily construct
|
|
network objects from existing addresses. (Contributed by Peter Moody
|
|
and Antoine Pitrou in :issue:`16531`.)
|
|
|
|
os
|
|
--
|
|
|
|
* :class:`os.stat_result` now has a :attr:`~os.stat_result.st_file_attributes`
|
|
attribute on Windows. (Contributed by Ben Hoyt in :issue:`21719`.)
|
|
|
|
re
|
|
--
|
|
|
|
* Number of capturing groups in regular expression is no longer limited by 100.
|
|
(Contributed by Serhiy Storchaka in :issue:`22437`.)
|
|
|
|
* Now unmatched groups are replaced with empty strings in :func:`re.sub`
|
|
and :func:`re.subn`. (Contributed by Serhiy Storchaka in :issue:`1519638`.)
|
|
|
|
shutil
|
|
------
|
|
|
|
* :func:`~shutil.move` now accepts a *copy_function* argument, allowing,
|
|
for example, :func:`~shutil.copy` to be used instead of the default
|
|
:func:`~shutil.copy2` if there is a need to ignore metadata. (Contributed by
|
|
Claudiu Popa in :issue:`19840`.)
|
|
|
|
signal
|
|
------
|
|
|
|
* Different constants of :mod:`signal` module are now enumeration values using
|
|
the :mod:`enum` module. This allows meaningful names to be printed during
|
|
debugging, instead of integer “magic numbers”. (Contributed by Giampaolo
|
|
Rodola' in :issue:`21076`.)
|
|
|
|
smtpd
|
|
-----
|
|
|
|
* Both :class:`~smtpd.SMTPServer` and :class:`smtpd.SMTPChannel` now accept a
|
|
*decode_data* keyword to determine if the DATA portion of the SMTP
|
|
transaction is decoded using the ``utf-8`` codec or is instead provided to
|
|
:meth:`~smtpd.SMTPServer.process_message` as a byte string. The default
|
|
is ``True`` for backward compatibility reasons, but will change to ``False``
|
|
in Python 3.6. (Contributed by Maciej Szulik in :issue:`19662`.)
|
|
|
|
* It is now possible to provide, directly or via name resolution, IPv6
|
|
addresses in the :class:`~smtpd.SMTPServer` constructor, and have it
|
|
successfully connect. (Contributed by Milan Oberkirch in :issue:`14758`.)
|
|
|
|
* :mod:`~smtpd.SMTPServer` now supports :rfc:`6531` via the *enable_SMTPUTF8*
|
|
constructor argument and a user-provided
|
|
:meth:`~smtpd.SMTPServer.process_smtputf8_message` method.
|
|
|
|
smtplib
|
|
-------
|
|
|
|
* A new :meth:`~smtplib.SMTP.auth` method provides a convenient way to
|
|
implement custom authentication mechanisms.
|
|
(Contributed by Milan Oberkirch in :issue:`15014`.)
|
|
|
|
sndhdr
|
|
------
|
|
|
|
* :func:`~sndhdr.what` and :func:`~sndhdr.whathdr` now return
|
|
:func:`~collections.namedtuple`.
|
|
(Contributed by Claudiu Popa in :issue:`18615`.)
|
|
|
|
socket
|
|
------
|
|
|
|
* New :meth:`socket.socket.sendfile` method allows to send a file over a socket
|
|
by using high-performance :func:`os.sendfile` function on UNIX resulting in
|
|
uploads being from 2x to 3x faster than when using plain
|
|
:meth:`socket.socket.send`.
|
|
(Contributed by Giampaolo Rodola' in :issue:`17552`.)
|
|
|
|
time
|
|
----
|
|
|
|
* The :func:`time.monotonic` function is now always available. (Contributed by
|
|
Victor Stinner in :issue:`22043`.)
|
|
|
|
wsgiref
|
|
-------
|
|
|
|
* *headers* parameter of :class:`wsgiref.headers.Headers` is now optional.
|
|
(Contributed by Pablo Torres Navarrete and SilentGhost in :issue:`5800`.)
|
|
|
|
xmlrpc
|
|
------
|
|
|
|
* :class:`xmlrpc.client.ServerProxy` is now a :term:`context manager`.
|
|
(Contributed by Claudiu Popa in :issue:`20627`.)
|
|
|
|
|
|
Optimizations
|
|
=============
|
|
|
|
The following performance enhancements have been added:
|
|
|
|
* Construction of ``bytes(int)`` (filled by zero bytes) is faster and use less
|
|
memory for large objects. ``calloc()`` is used instead of ``malloc()`` to
|
|
allocate memory for these objects.
|
|
|
|
* Some operations on :class:`~ipaddress.IPv4Network` and
|
|
:class:`~ipaddress.IPv6Network` have been massively sped up, such as
|
|
:meth:`~ipaddress.IPv4Network.subnets`, :meth:`~ipaddress.IPv4Network.supernet`,
|
|
:func:`~ipaddress.summarize_address_range`, :func:`~ipaddress.collapse_addresses`.
|
|
The speed up can range from 3x to 15x.
|
|
(:issue:`21486`, :issue:`21487`, :issue:`20826`)
|
|
|
|
|
|
Build and C API Changes
|
|
=======================
|
|
|
|
Changes to Python's build process and to the C API include:
|
|
|
|
* New ``calloc`` functions:
|
|
|
|
* :c:func:`PyMem_RawCalloc`
|
|
* :c:func:`PyMem_Calloc`
|
|
* :c:func:`PyObject_Calloc`
|
|
* :c:func:`_PyObject_GC_Calloc`
|
|
|
|
|
|
Deprecated
|
|
==========
|
|
|
|
Unsupported Operating Systems
|
|
-----------------------------
|
|
|
|
* None yet.
|
|
|
|
|
|
Deprecated Python modules, functions and methods
|
|
------------------------------------------------
|
|
|
|
* The :mod:`formatter` module has now graduated to full deprecation and is still
|
|
slated for removal in Python 3.6.
|
|
|
|
* :mod:`smtpd` has in the past always decoded the DATA portion of email
|
|
messages using the ``utf-8`` codec. This can now be controlled by the new
|
|
*decode_data* keyword to :class:`~smtpd.SMTPServer`. The default value is
|
|
``True``, but this default is deprecated. Specify the *decode_data* keyword
|
|
with an appropriate value to avoid the deprecation warning.
|
|
|
|
|
|
Deprecated functions and types of the C API
|
|
-------------------------------------------
|
|
|
|
* None yet.
|
|
|
|
|
|
Deprecated features
|
|
-------------------
|
|
|
|
* None yet.
|
|
|
|
|
|
Removed
|
|
=======
|
|
|
|
API and Feature Removals
|
|
------------------------
|
|
|
|
The following obsolete and previously deprecated APIs and features have been
|
|
removed:
|
|
|
|
* The ``__version__`` attribute has been dropped from the email package. The
|
|
email code hasn't been shipped separately from the stdlib for a long time,
|
|
and the ``__version__`` string was not updated in the last few releases.
|
|
|
|
* The internal ``Netrc`` class in the :mod:`ftplib` module was deprecated in
|
|
3.4, and has now been removed.
|
|
(Contributed by Matt Chaput in :issue:`6623`.)
|
|
|
|
Porting to Python 3.5
|
|
=====================
|
|
|
|
This section lists previously described changes and other bugfixes
|
|
that may require changes to your code.
|
|
|
|
Changes in the Python API
|
|
-------------------------
|
|
|
|
* Before Python 3.5, a :class:`datetime.time` object was considered to be false
|
|
if it represented midnight in UTC. This behavior was considered obscure and
|
|
error-prone and has been removed in Python 3.5. See :issue:`13936` for full
|
|
details.
|
|
|
|
* :meth:`ssl.SSLSocket.send()` now raises either :exc:`ssl.SSLWantReadError`
|
|
or :exc:`ssl.SSLWantWriteError` on a non-blocking socket if the operation
|
|
would block. Previously, it would return 0. See :issue:`20951`.
|
|
|
|
* The ``__name__`` attribute of generator is now set from the function name,
|
|
instead of being set from the code name. Use ``gen.gi_code.co_name`` to
|
|
retrieve the code name. Generators also have a new ``__qualname__``
|
|
attribute, the qualified name, which is now used for the representation
|
|
of a generator (``repr(gen)``). See :issue:`21205`.
|
|
|
|
* The deprecated "strict" mode and argument of :class:`~html.parser.HTMLParser`,
|
|
:meth:`HTMLParser.error`, and the :exc:`HTMLParserError` exception have been
|
|
removed. (Contributed by Ezio Melotti in :issue:`15114`.)
|
|
The *convert_charrefs* argument of :class:`~html.parser.HTMLParser` is
|
|
now ``True`` by default. (Contributed by Berker Peksag in :issue:`21047`.)
|
|
|
|
* Although it is not formally part of the API, it is worth noting for porting
|
|
purposes (ie: fixing tests) that error messages that were previously of the
|
|
form "'sometype' does not support the buffer protocol" are now of the form "a
|
|
bytes-like object is required, not 'sometype'". (Contributed by Ezio Melotti
|
|
in :issue:`16518`.)
|
|
|
|
Changes in the C API
|
|
--------------------
|
|
|
|
* The :c:type:`PyMemAllocator` structure was renamed to
|
|
:c:type:`PyMemAllocatorEx` and a new ``calloc`` field was added.
|