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diff --git a/Doc/whatsnew/3.5.rst b/Doc/whatsnew/3.5.rst new file mode 100644 index 0000000..7fb0fd5 --- /dev/null +++ b/Doc/whatsnew/3.5.rst @@ -0,0 +1,392 @@ +**************************** + 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:`4XX` - 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`.) + +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`). + +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 (: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. + + +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`). + +Changes in the C API +-------------------- + +* The :c:type:`PyMemAllocator` structure was renamed to + :c:type:`PyMemAllocatorEx` and a new ``calloc`` field was added. |