cpython/Misc/NEWS.d/3.7.0b4.rst

.. bpo: 33363
.. date: 2018-04-26-22-48-28
.. nonce: 8RCnN2
.. release date: 2018-05-02
.. section: Core and Builtins

Raise a SyntaxError for ``async with`` and ``async for`` statements outside
of async functions.

..

.. bpo: 33128
.. date: 2018-04-24-22-31-04
.. nonce: g2yLuf
.. section: Core and Builtins

Fix a bug that causes PathFinder to appear twice on sys.meta_path. Patch by
Pablo Galindo Salgado.

..

.. bpo: 33312
.. date: 2018-04-19-08-30-07
.. nonce: mDe2iL
.. section: Core and Builtins

Fixed clang ubsan (undefined behavior sanitizer) warnings in dictobject.c by
adjusting how the internal struct _dictkeysobject shared keys structure is
declared.

..

.. bpo: 33231
.. date: 2018-04-05-22-20-44
.. nonce: 3Jmo0q
.. section: Core and Builtins

Fix potential memory leak in ``normalizestring()``.

..

.. bpo: 33205
.. date: 2018-04-03-00-58-41
.. nonce: lk2F3r
.. section: Core and Builtins

Change dict growth function from
``round_up_to_power_2(used*2+hashtable_size/2)`` to
``round_up_to_power_2(used*3)``.  Previously, dict is shrinked only when
``used == 0``. Now dict has more chance to be shrinked.

..

.. bpo: 29922
.. date: 2018-04-03-00-30-25
.. nonce: CdLuMl
.. section: Core and Builtins

Improved error messages in 'async with' when ``__aenter__()`` or
``__aexit__()`` return non-awaitable object.

..

.. bpo: 33199
.. date: 2018-04-02-09-32-40
.. nonce: TPnxQu
.. section: Core and Builtins

Fix ``ma_version_tag`` in dict implementation is uninitialized when copying
from key-sharing dict.

..

.. bpo: 33281
.. date: 2018-05-01-22-35-50
.. nonce: d4jOt4
.. section: Library

Fix ctypes.util.find_library regression on macOS.

..

.. bpo: 33383
.. date: 2018-04-29-11-15-38
.. nonce: g32YWn
.. section: Library

Fixed crash in the get() method of the :mod:`dbm.ndbm` database object when
it is called with a single argument.

..

.. bpo: 33329
.. date: 2018-04-23-13-21-39
.. nonce: lQ-Eod
.. section: Library

Fix multiprocessing regression on newer glibcs

..

.. bpo: 991266
.. date: 2018-04-21-00-24-08
.. nonce: h93TP_
.. section: Library

Fix quoting of the ``Comment`` attribute of
:class:`http.cookies.SimpleCookie`.

..

.. bpo: 33131
.. date: 2018-04-20-10-43-17
.. nonce: L2E977
.. section: Library

Upgrade bundled version of pip to 10.0.1.

..

.. bpo: 33308
.. date: 2018-04-18-19-12-25
.. nonce: fW75xi
.. section: Library

Fixed a crash in the :mod:`parser` module when converting an ST object to a
tree of tuples or lists with ``line_info=False`` and ``col_info=True``.

..

.. bpo: 33266
.. date: 2018-04-16-15-59-21
.. nonce: w2PAm-
.. section: Library

lib2to3 now recognizes ``rf'...'`` strings.

..

.. bpo: 11594
.. date: 2018-04-16-08-42-03
.. nonce: QLo4vv
.. section: Library

Ensure line-endings are respected when using lib2to3.

..

.. bpo: 33254
.. date: 2018-04-13-15-14-47
.. nonce: DS4KFK
.. section: Library

Have :func:`importlib.resources.contents` and
:meth:`importlib.abc.ResourceReader.contents` return an :term:`iterable`
instead of an :term:`iterator`.

..

.. bpo: 33256
.. date: 2018-04-10-20-57-14
.. nonce: ndHkqu
.. section: Library

Fix display of ``<module>`` call in the html produced by ``cgitb.html()``.
Patch by Stéphane Blondon.

..

.. bpo: 33185
.. date: 2018-04-08-22-54-07
.. nonce: Id-Ba9
.. section: Library

Fixed regression when running pydoc with the :option:`-m` switch. (The
regression was introduced in 3.7.0b3 by the resolution of :issue:`33053`)
This fix also changed pydoc to add ``os.getcwd()`` to :data:`sys.path` when
necessary, rather than adding ``"."``.

..

.. bpo: 33169
.. date: 2018-04-06-14-56-26
.. nonce: ByhDqb
.. section: Library

Delete entries of ``None`` in :data:`sys.path_importer_cache` when
:meth:`importlib.machinery.invalidate_caches` is called.

..

.. bpo: 33217
.. date: 2018-04-05-13-36-09
.. nonce: FfOKDI
.. section: Library

Deprecate looking up non-Enum objects in Enum classes and Enum members (will
raise :exc:`TypeError` in 3.8+).

..

.. bpo: 33203
.. date: 2018-04-05-11-09-45
.. nonce: Hje9Py
.. section: Library

``random.Random.choice()`` now raises ``IndexError`` for empty sequences
consistently even when called from subclasses without a ``getrandbits()``
implementation.

..

.. bpo: 33224
.. date: 2018-04-04-23-41-30
.. nonce: pyR0jB
.. section: Library

Update difflib.mdiff() for :pep:`479`.  Convert an uncaught StopIteration in a
generator into a return-statement.

..

.. bpo: 33209
.. date: 2018-04-03-10-37-13
.. nonce: 9sGWE_
.. section: Library

End framing at the end of C implementation of :func:`pickle.Pickler.dump`.

..

.. bpo: 20104
.. date: 2018-04-01-19-21-04
.. nonce: -AKcGa
.. section: Library

Improved error handling and fixed a reference leak in
:func:`os.posix_spawn()`.

..

.. bpo: 33175
.. date: 2018-03-29-04-32-25
.. nonce: _zs1yM
.. section: Library

In dataclasses, Field.__set_name__ now looks up the __set_name__ special
method on the class, not the instance, of the default value.

..

.. bpo: 33097
.. date: 2018-03-18-16-48-23
.. nonce: Yl4gI2
.. section: Library

Raise RuntimeError when ``executor.submit`` is called during interpreter
shutdown.

..

.. bpo: 31908
.. date: 2017-10-31
.. nonce: g4xh8x
.. section: Library

Fix output of cover files for ``trace`` module command-line tool. Previously
emitted cover files only when ``--missing`` option was used. Patch by
Michael Selik.

..

.. bpo: 33378
.. date: 2018-04-29-04-02-18
.. nonce: -anAHN
.. section: Documentation

Add Korean language switcher for https://docs.python.org/3/

..

.. bpo: 33276
.. date: 2018-04-20-14-09-36
.. nonce: rA1z_3
.. section: Documentation

Clarify that the ``__path__`` attribute on modules cannot be just any value.

..

.. bpo: 33201
.. date: 2018-04-01-21-03-41
.. nonce: aa8Lkl
.. section: Documentation

Modernize documentation for writing C extension types.

..

.. bpo: 33195
.. date: 2018-04-01-14-30-36
.. nonce: dRS-XX
.. section: Documentation

Deprecate ``Py_UNICODE`` usage in ``c-api/arg`` document. ``Py_UNICODE``
related APIs are deprecated since Python 3.3, but it is missed in the
document.

..

.. bpo: 8243
.. date: 2018-01-13-20-30-53
.. nonce: s98r28
.. section: Documentation

Add a note about curses.addch and curses.addstr exception behavior when
writing outside a window, or pad.

..

.. bpo: 32337
.. date: 2017-12-22-17-29-37
.. nonce: eZe-ID
.. section: Documentation

Update documentation related with ``dict`` order.

..

.. bpo: 33358
.. date: 2018-04-27-11-46-35
.. nonce: _OcR59
.. section: Tests

Fix ``test_embed.test_pre_initialization_sys_options()`` when the
interpreter is built with ``--enable-shared``.

..

.. bpo: 33394
.. date: 2018-04-30-17-36-46
.. nonce: _Vdi4t
.. section: Build

Enable the verbose build for extension modules, when GNU make is passed
macros on the command line.

..

.. bpo: 33393
.. date: 2018-04-30-17-19-37
.. nonce: HkVCqI
.. section: Build

Update config.guess and config.sub files.

..

.. bpo: 33377
.. date: 2018-04-30-16-53-00
.. nonce: QBh6vP
.. section: Build

Add new triplets for mips r6 and riscv variants (used in extension
suffixes).

..

.. bpo: 32232
.. date: 2018-04-17-00-38-19
.. nonce: o7G_UO
.. section: Build

By default, modules configured in ``Modules/Setup`` are no longer built with
``-DPy_BUILD_CORE``. Instead, modules that specifically need that preprocessor
definition include it in their individual entries.

..

.. bpo: 33182
.. date: 2018-03-30-14-55-48
.. nonce: CePczb
.. section: Build

The embedding tests can once again be built with clang 6.0

..

.. bpo: 33184
.. date: 2018-04-13-11-28-55
.. nonce: 7YhqQE
.. section: Windows

Update Windows installer to use OpenSSL 1.1.0h.

..

.. bpo: 33184
.. date: 2018-04-07-00-51-34
.. nonce: 3j208P
.. section: macOS

Update macOS installer build to use OpenSSL 1.1.0h.

..

.. bpo: 21474
.. date: 2018-04-29-16-13-02
.. nonce: bglg-F
.. section: IDLE

Update word/identifier definition from ascii to unicode. In text and entry
boxes, this affects selection by double-click, movement left/right by
control-left/right, and deletion left/right by control-BACKSPACE/DEL.

..

.. bpo: 33204
.. date: 2018-04-02-00-28-13
.. nonce: NBsuIv
.. section: IDLE

IDLE: consistently color invalid string prefixes. A 'u' string prefix cannot
be paired with either 'r' or 'f'. Consistently color as much of the prefix,
starting at the right, as is valid. Revise and extend colorizer test.

..

.. bpo: 33189
.. date: 2018-04-03-18-10-00
.. nonce: QrXR00
.. section: Tools/Demos

:program:`pygettext.py` now recognizes only literal strings as docstrings
and translatable strings, and rejects bytes literals and f-string
expressions.

..

.. bpo: 31920
.. date: 2018-03-26-18-54-24
.. nonce: u_WKsT
.. section: Tools/Demos

Fixed handling directories as arguments in the ``pygettext`` script. Based
on patch by Oleg Krasnikov.

..

.. bpo: 29673
.. date: 2018-03-16-17-25-05
.. nonce: m8QtaW
.. section: Tools/Demos

Fix pystackv and pystack gdbinit macros.

..

.. bpo: 31583
.. date: 2017-09-26-10-11-21
.. nonce: TM90_H
.. section: Tools/Demos

Fix 2to3 for using with --add-suffix option but without --output-dir option
for relative path to files in current directory.