3.11.0a5 - Cpython — ContextQMD

.. bpo: 45773 .. date: 2022-02-01-14-30-56 .. nonce: Up77LD .. release date: 2022-02-03 .. section: Core and Builtins

Remove two invalid "peephole" optimizations from the bytecode compiler.

.. bpo: 46564 .. date: 2022-02-01-10-23-21 .. nonce: 6Xc2_H .. section: Core and Builtins

Do not create frame objects when creating :class:super object. Patch by Kumar Aditya.

.. bpo: 45885 .. date: 2022-02-01-01-17-28 .. nonce: CjyNf_ .. section: Core and Builtins

Added more fined-grained specialization failure stats regarding the COMPARE_OP bytecode.

.. bpo: 44977 .. date: 2022-01-30-18-23-08 .. nonce: BQV_zS .. section: Core and Builtins

The delegation of :func:int to :meth:__trunc__ is now deprecated. Calling int(a) when type(a) implements :meth:__trunc__ but not :meth:__int__ or :meth:__index__ now raises a :exc:DeprecationWarning.

.. bpo: 46458 .. date: 2022-01-27-10-49-34 .. nonce: 5Gm3Gv .. section: Core and Builtins

Reorder code emitted by the compiler for a :keyword:try-:keyword:except block so that the :keyword:else block's code immediately follows the :keyword:try body (without a jump). This is more optimal for the happy path.

.. bpo: 46527 .. date: 2022-01-25-19-34-55 .. nonce: mQLNPk .. section: Core and Builtins

Allow passing iterable as a keyword argument to :func:enumerate again. Patch by Jelle Zijlstra.

.. bpo: 46528 .. date: 2022-01-25-17-40-07 .. nonce: 2Qmni9 .. section: Core and Builtins

Replace several stack manipulation instructions (DUP_TOP, DUP_TOP_TWO, ROT_TWO, ROT_THREE, ROT_FOUR, and ROT_N) with new :opcode:COPY and :opcode:SWAP instructions.

.. bpo: 46329 .. date: 2022-01-25-11-44-17 .. nonce: SEhynE .. section: Core and Builtins

Use two or three bytecodes to implement most calls.

Calls without named arguments are implemented as a sequence of two instructions: PRECALL; CALL. Calls with named arguments are implemented as a sequence of three instructions: PRECALL; KW_NAMES; CALL. There are two different PRECALL instructions: PRECALL_FUNTION and PRECALL_METHOD. The latter pairs with LOAD_METHOD.

This partition into pre-call and call allows better specialization, and thus better performance ultimately.

There is no change in semantics.

.. bpo: 46503 .. date: 2022-01-24-21-24-41 .. nonce: 4UrPsE .. section: Core and Builtins

Fix an assert when parsing some invalid \N escape sequences in f-strings.

.. bpo: 46431 .. date: 2022-01-24-16-58-01 .. nonce: N6mKAx .. section: Core and Builtins

Improve error message on invalid calls to :meth:BaseExceptionGroup.__new__.

.. bpo: 46476 .. date: 2022-01-24-15-39-34 .. nonce: cvP1Mr .. section: Core and Builtins

Fix memory leak in code objects generated by deepfreeze. Patch by Kumar Aditya.

.. bpo: 46481 .. date: 2022-01-23-06-56-33 .. nonce: X_FfnB .. section: Core and Builtins

Speed up calls to :meth:weakref.ref.__call__ by using the :pep:590 vectorcall calling convention. Patch by Donghee Na.

.. bpo: 46417 .. date: 2022-01-22-14-39-23 .. nonce: 3U5SfN .. section: Core and Builtins

Fix a race condition on setting a type __bases__ attribute: the internal function add_subclass() now gets the PyTypeObject.tp_subclasses member after calling :c:func:PyWeakref_NewRef which can trigger a garbage collection which can indirectly modify PyTypeObject.tp_subclasses. Patch by Victor Stinner.

.. bpo: 46417 .. date: 2022-01-21-12-24-14 .. nonce: i3IqMf .. section: Core and Builtins

python -X showrefcount now shows the total reference count after clearing and destroyed the main Python interpreter. Previously, it was shown before. Patch by Victor Stinner.

.. bpo: 43683 .. date: 2022-01-20-17-13-49 .. nonce: BqQ26Z .. section: Core and Builtins

Add ASYNC_GEN_WRAP opcode to wrap the value to be yielded in async generators. Removes the need to special case async generators in the YIELD_VALUE instruction.

.. bpo: 46407 .. date: 2022-01-17-23-12-01 .. nonce: 2_5a7R .. section: Core and Builtins

Optimize some modulo operations in Objects/longobject.c. Patch by Jeremiah Vivian.

.. bpo: 46409 .. date: 2022-01-17-12-57-27 .. nonce: HouS6m .. section: Core and Builtins

Add new RETURN_GENERATOR bytecode to make generators. Simplifies calling Python functions in the VM, as they no longer any need to special case generator functions.

Also add JUMP_NO_INTERRUPT bytecode that acts like JUMP_ABSOLUTE, but does not check for interrupts.

.. bpo: 46406 .. date: 2022-01-16-15-40-11 .. nonce: g0mke- .. section: Core and Builtins

The integer division // implementation has been optimized to better let the compiler understand its constraints. It can be 20% faster on the amd64 platform when dividing an int by a value smaller than 2**30.

.. bpo: 46383 .. date: 2022-01-14-20-55-34 .. nonce: v8MTl4 .. section: Library

Fix invalid signature of _zoneinfo's module_free function to resolve a crash on wasm32-emscripten platform.

.. bpo: 46361 .. date: 2022-01-12-17-15-17 .. nonce: mgI_j_ .. section: Core and Builtins

Ensure that "small" integers created by :meth:int.from_bytes and :class:decimal.Decimal are properly cached.

.. bpo: 46161 .. date: 2021-12-23-12-32-45 .. nonce: EljBmu .. section: Core and Builtins

Fix the class building error when the arguments are constants and CALL_FUNCTION_EX is used.

.. bpo: 46028 .. date: 2021-12-16-15-04-58 .. nonce: zfWacB .. section: Core and Builtins

Fixes calculation of :data:sys._base_executable when inside a virtual environment that uses symlinks with different binary names than the base environment provides.

.. bpo: 46091 .. date: 2021-12-16-00-24-00 .. nonce: rJ_e_e .. section: Core and Builtins

Correctly calculate indentation levels for lines with whitespace character that are ended by line continuation characters. Patch by Pablo Galindo

.. bpo: 30512 .. date: 2021-12-12-00-49-19 .. nonce: nU9E9V .. section: Library

Add CAN Socket support for NetBSD.

.. bpo: 46045 .. date: 2021-12-11-11-36-48 .. nonce: sfThay .. section: Build

Do not use POSIX semaphores on NetBSD

.. bpo: 44024 .. date: 2021-05-04-21-55-49 .. nonce: M9m8Qd .. section: Core and Builtins

Improve the :exc:TypeError message for non-string second arguments passed to the built-in functions :func:getattr and :func:hasattr. Patch by Géry Ogam.

.. bpo: 46624 .. date: 2022-02-03-12-07-41 .. nonce: f_Qqh0 .. section: Library

Restore support for non-integer arguments of :func:random.randrange and :func:random.randint.

.. bpo: 46591 .. date: 2022-01-31-15-40-38 .. nonce: prBD1M .. section: Library

Make the IDLE doc URL on the About IDLE dialog clickable.

.. bpo: 46565 .. date: 2022-01-28-19-48-31 .. nonce: bpZXO4 .. section: Library

Remove loop variables that are leaking into modules' namespaces.

.. bpo: 46553 .. date: 2022-01-28-08-47-53 .. nonce: f7Uc96 .. section: Library

In :func:typing.get_type_hints, support evaluating bare stringified ClassVar annotations. Patch by Gregory Beauregard.

.. bpo: 46544 .. date: 2022-01-27-13-30-02 .. nonce: oFDVWj .. section: Library

Don't leak x & uspace intermediate vars in :class:textwrap.TextWrapper.

.. bpo: 46487 .. date: 2022-01-27-12-24-38 .. nonce: UDkN2z .. section: Library

Add the get_write_buffer_limits method to :class:asyncio.transports.WriteTransport and to the SSL transport.

.. bpo: 45173 .. date: 2022-01-27-11-16-59 .. nonce: wreRF2 .. section: Library

Note the configparser deprecations will be removed in Python 3.12.

.. bpo: 45162 .. date: 2022-01-26-23-58-48 .. nonce: 4Jmg_j .. section: Library

The deprecated :mod:unittest APIs removed in 3.11a1 have been temporarily restored to be removed in 3.12 while cleanups in external projects go in.

.. bpo: 46539 .. date: 2022-01-26-20-36-30 .. nonce: 23iW1d .. section: Library

In :func:typing.get_type_hints, support evaluating stringified ClassVar and Final annotations inside Annotated. Patch by Gregory Beauregard.

.. bpo: 46510 .. date: 2022-01-25-10-59-41 .. nonce: PM5svI .. section: Library

Add missing test for :class:types.TracebackType and :class:types.FrameType. Calculate them directly from the caught exception without calling :func:sys.exc_info.

.. bpo: 46491 .. date: 2022-01-24-23-55-30 .. nonce: jmIKHo .. section: Library

Allow :data:typing.Annotated to wrap :data:typing.Final and :data:typing.ClassVar. Patch by Gregory Beauregard.

.. bpo: 46483 .. date: 2022-01-24-13-00-09 .. nonce: 9XnmKp .. section: Library

Remove :meth:~object.__class_getitem__ from :class:pathlib.PurePath as this class was not supposed to be generic.

.. bpo: 46436 .. date: 2022-01-23-19-37-00 .. nonce: Biz1p9 .. section: Library

Fix command-line option -d/--directory in module :mod:http.server which is ignored when combined with command-line option --cgi. Patch by Géry Ogam.

.. bpo: 41403 .. date: 2022-01-23-18-04-45 .. nonce: SgoHqV .. section: Library

Make :meth:mock.patch raise a :exc:TypeError with a relevant error message on invalid arg. Previously it allowed a cryptic :exc:AttributeError to escape.

.. bpo: 46474 .. date: 2022-01-22-14-49-10 .. nonce: eKQhvx .. section: Library

In importlib.metadata.EntryPoint.pattern, avoid potential REDoS by limiting ambiguity in consecutive whitespace.

.. bpo: 46474 .. date: 2022-01-22-14-45-46 .. nonce: 2DUC62 .. section: Library

Removed private method from importlib.metadata.Path. Sync with importlib_metadata 4.10.0.

.. bpo: 46470 .. date: 2022-01-22-13-17-35 .. nonce: MnNhgU .. section: Library

Remove unused branch from typing._remove_dups_flatten

.. bpo: 46469 .. date: 2022-01-22-05-05-08 .. nonce: plUab5 .. section: Library

:mod:asyncio generic classes now return :class:types.GenericAlias in __class_getitem__ instead of the same class.

.. bpo: 41906 .. date: 2022-01-21-18-19-45 .. nonce: YBaquj .. section: Library

Support passing filter instances in the filters values of handlers and loggers in the dictionary passed to :func:logging.config.dictConfig.

.. bpo: 46422 .. date: 2022-01-20-10-35-50 .. nonce: 1UAEHL .. section: Library

Use dis.Positions in dis.Instruction instead of a regular tuple.

.. bpo: 46434 .. date: 2022-01-20-10-35-10 .. nonce: geS-aP .. section: Library

:mod:pdb now gracefully handles help when :attr:~module.__doc__ is missing, for example when run with pregenerated optimized .pyc files.

.. bpo: 43869 .. date: 2022-01-18-17-24-21 .. nonce: NayN12 .. section: Library

Python uses the same time Epoch on all platforms. Add an explicit unit test to ensure that it's the case. Patch by Victor Stinner.

.. bpo: 46414 .. date: 2022-01-17-10-00-02 .. nonce: Ld0b_y .. section: Library

Add :func:typing.reveal_type. Patch by Jelle Zijlstra.

.. bpo: 40280 .. date: 2022-01-16-14-07-14 .. nonce: LtFHfF .. section: Library

:mod:subprocess now imports Windows-specific imports when msvcrt module is available, and POSIX-specific imports on all other platforms. This gives a clean exception when _posixsubprocess is not available (e.g. Emscripten browser target).

.. bpo: 40066 .. date: 2022-01-13-11-41-24 .. nonce: 1QuVli .. section: Library

IntEnum, IntFlag, and StrEnum use the mixed-in type for their str() and format() output.

.. bpo: 46316 .. date: 2022-01-09-15-04-56 .. nonce: AMTyd0 .. section: Library

Optimize :meth:pathlib.Path.iterdir by removing an unnecessary check for special entries.

.. bpo: 29688 .. date: 2022-01-05-03-21-21 .. nonce: W06bSH .. section: Library

Document :meth:pathlib.Path.absolute (which has always existed).

.. bpo: 43012 .. date: 2022-01-05-03-09-29 .. nonce: RVhLIL .. section: Library

The pathlib module's obsolete and internal _Accessor class has been removed to prepare the terrain for upcoming enhancements to the module.

.. bpo: 46258 .. date: 2022-01-04-18-05-25 .. nonce: DYgwRo .. section: Library

Speed up :func:math.isqrt for small positive integers by replacing two division steps with a lookup table.

.. bpo: 46242 .. date: 2022-01-03-16-25-06 .. nonce: f4l_CL .. section: Library

Improve error message when creating a new :class:enum.Enum type subclassing an existing Enum with _member_names_ using :meth:enum.Enum.__call__.

.. bpo: 43118 .. date: 2021-12-29-14-42-09 .. nonce: BoVi_5 .. section: Library

Fix a bug in :func:inspect.signature that was causing it to fail on some subclasses of classes with a __text_signature__ referencing module globals. Patch by Weipeng Hong.

.. bpo: 26552 .. date: 2021-12-29-13-42-55 .. nonce: 1BqeAn .. section: Library

Fixed case where failing :func:asyncio.ensure_future did not close the coroutine. Patch by Kumar Aditya.

.. bpo: 21987 .. date: 2021-12-28-11-55-10 .. nonce: avBK-p .. section: Library

Fix an issue with :meth:tarfile.TarFile.getmember getting a directory name with a trailing slash.

.. bpo: 46124 .. date: 2021-12-18-18-41-30 .. nonce: ESPrb7 .. section: Library

Update :mod:zoneinfo to rely on importlib.resources traversable API.

.. bpo: 46103 .. date: 2021-12-16-23-42-54 .. nonce: LMnZAN .. section: Library

Now :func:inspect.getmembers only gets :attr:__bases__ attribute from class type. Patch by Weipeng Hong.

.. bpo: 46080 .. date: 2021-12-15-06-29-00 .. nonce: AuQpLt .. section: Library

Fix exception in argparse help text generation if a :class:argparse.BooleanOptionalAction argument's default is argparse.SUPPRESS and it has help specified. Patch by Felix Fontein.

.. bpo: 44791 .. date: 2021-07-31-23-18-50 .. nonce: 4jFdpO .. section: Library

Fix substitution of :class:~typing.ParamSpec in :data:~typing.Concatenate with different parameter expressions. Substitution with a list of types returns now a tuple of types. Substitution with Concatenate returns now a Concatenate with concatenated lists of arguments.

.. bpo: 46463 .. date: 2022-01-21-21-33-48 .. nonce: fBbdTG .. section: Documentation

Fixes :file:escape4chm.py script used when building the CHM documentation file

.. bpo: 43478 .. date: 2022-02-03-00-21-32 .. nonce: 0nfcam .. section: Tests

Mocks can no longer be provided as the specs for other Mocks. As a result, an already-mocked object cannot be passed to mock.Mock(). This can uncover bugs in tests since these Mock-derived Mocks will always pass certain tests (e.g. isinstance) and builtin assert functions (e.g. assert_called_once_with) will unconditionally pass.

.. bpo: 46616 .. date: 2022-02-02-18-14-38 .. nonce: URvBtE .. section: Tests

Ensures test_importlib.test_windows cleans up registry keys after completion.

.. bpo: 44359 .. date: 2022-02-02-02-24-04 .. nonce: kPPSmN .. section: Tests

test_ftplib now silently ignores socket errors to prevent logging unhandled threading exceptions. Patch by Victor Stinner.

.. bpo: 46600 .. date: 2022-02-01-17-13-53 .. nonce: FMCk8Z .. section: Tests

Fix test_gdb.test_pycfunction() for Python built with clang -Og. Tolerate inlined functions in the gdb traceback. Patch by Victor Stinner.

.. bpo: 46542 .. date: 2022-01-31-17-34-13 .. nonce: RTMm1T .. section: Tests

Fix a Python crash in test_lib2to3 when using Python built in debug mode: limit the recursion limit. Patch by Victor Stinner.

.. bpo: 46576 .. date: 2022-01-29-12-37-53 .. nonce: -prRaV .. section: Tests

test_peg_generator now disables compiler optimization when testing compilation of its own C extensions to significantly speed up the testing on non-debug builds of CPython.

.. bpo: 46542 .. date: 2022-01-28-01-17-10 .. nonce: xRLTdj .. section: Tests

Fix test_json tests checking for :exc:RecursionError: modify these tests to use support.infinite_recursion(). Patch by Victor Stinner.

.. bpo: 13886 .. date: 2022-01-17-13-10-04 .. nonce: 5mZH4b .. section: Tests

Skip test_builtin PTY tests on non-ASCII characters if the readline module is loaded. The readline module changes input() behavior, but test_builtin is not intended to test the readline module. Patch by Victor Stinner.

.. bpo: 40280 .. date: 2022-01-16-14-11-57 .. nonce: fNnFfx .. section: Tests

Add :func:test.support.requires_fork decorators to mark tests that require a working :func:os.fork.

.. bpo: 40280 .. date: 2022-01-14-23-22-41 .. nonce: nHLWoD .. section: Tests

Add :func:test.support.requires_subprocess decorator to mark tests which require working :mod:subprocess module or os.spawn*. The wasm32-emscripten platform has no support for processes.

.. bpo: 46126 .. date: 2021-12-18-22-23-50 .. nonce: 0LH3Yb .. section: Tests

Disable 'descriptions' when running tests internally.

.. bpo: 46602 .. date: 2022-02-02-02-06-07 .. nonce: 8GaOZ2 .. section: Build

Tidied up configure.ac so that conftest.c is truncated rather than appended. This assists in the case where the 'rm' of conftest.c fails to happen between tests. Downstream issues such as a clobbered SOABI can result.

.. bpo: 46600 .. date: 2022-02-01-14-07-37 .. nonce: NNLnfj .. section: Build

Fix the test checking if the C compiler supports -Og option in the ./configure script to also use -Og on clang which supports it. Patch by Victor Stinner.

.. bpo: 38472 .. date: 2022-01-26-22-59-12 .. nonce: RxfLho .. section: Build

Fix GCC detection in setup.py when cross-compiling. The C compiler is now run with LC_ALL=C. Previously, the detection failed with a German locale.

.. bpo: 46513 .. date: 2022-01-25-12-32-37 .. nonce: mPm9B4 .. section: Build

:program:configure no longer uses AC_C_CHAR_UNSIGNED macro and pyconfig.h no longer defines reserved symbol __CHAR_UNSIGNED__.

.. bpo: 46471 .. date: 2022-01-22-11-06-23 .. nonce: 03snrE .. section: Build

Use global singletons for single byte bytes objects in deepfreeze.

.. bpo: 46443 .. date: 2022-01-20-05-27-07 .. nonce: udCVII .. section: Build

Deepfreeze now uses cached small integers as it saves some space for common small integers.

.. bpo: 46429 .. date: 2022-01-19-04-36-15 .. nonce: y0OtVL .. section: Build

Merge all deep-frozen files into one for space savings. Patch by Kumar Aditya.

.. bpo: 45569 .. date: 2022-01-09-11-24-54 .. nonce: zCIENy .. section: Build

The build now defaults to using 30-bit digits for Python integers. Previously either 15-bit or 30-bit digits would be selected, depending on the platform. 15-bit digits may still be selected using the --enable-big-digits=15 option to the configure script, or by defining PYLONG_BITS_IN_DIGIT in pyconfig.h.

.. bpo: 45925 .. date: 2022-01-08-12-43-31 .. nonce: 38F3NO .. section: Build

Update Windows installer to use SQLite 3.37.2.

.. bpo: 43112 .. date: 2021-02-10-17-54-04 .. nonce: H5Lat6 .. section: Build

Detect musl libc as a separate SOABI (tagged as linux-musl).

.. bpo: 33125 .. date: 2022-01-25-14-48-39 .. nonce: 5WyY_J .. section: Windows

The traditional EXE/MSI based installer for Windows is now available for ARM64

.. bpo: 46362 .. date: 2022-01-13-22-31-09 .. nonce: f2cuEb .. section: Windows

os.path.abspath("C:\CON") is now fixed to return "\.\CON", not the same path. The regression was true of all legacy DOS devices such as COM1, LPT1, or NUL.

.. bpo: 44934 .. date: 2021-09-01-10-48-11 .. nonce: W1xPATH .. section: Windows

The installer now offers a command-line only option to add the installation directory to the end of :envvar:PATH instead of at the start.

.. bpo: 45925 .. date: 2022-01-26-12-04-09 .. nonce: yBSiYO .. section: macOS

Update macOS installer to SQLite 3.37.2.

.. bpo: 45296 .. date: 2022-01-26-19-33-55 .. nonce: LzZKdU .. section: IDLE

Clarify close, quit, and exit in IDLE. In the File menu, 'Close' and 'Exit' are now 'Close Window' (the current one) and 'Exit' is now 'Exit IDLE' (by closing all windows). In Shell, 'quit()' and 'exit()' mean 'close Shell'. If there are no other windows, this also exits IDLE.

.. bpo: 40170 .. date: 2022-01-27-02-51-22 .. nonce: uPolek .. section: C API

Remove the PyHeapType_GET_MEMBERS() macro. It was exposed in the public C API by mistake, it must only be used by Python internally. Use the PyTypeObject.tp_members member instead. Patch by Victor Stinner.

.. bpo: 40170 .. date: 2022-01-27-02-37-18 .. nonce: XxQB0i .. section: C API

Move _Py_GetAllocatedBlocks() and _PyObject_DebugMallocStats() private functions to the internal C API. Patch by Victor Stinner.

.. bpo: 46433 .. date: 2022-01-19-16-51-54 .. nonce: Er9ApS .. section: C API

The internal function _PyType_GetModuleByDef now correctly handles inheritance patterns involving static types.

.. bpo: 45459 .. date: 2021-10-18-16-54-24 .. nonce: Y1pEZs .. section: C API

:c:type:Py_buffer and various Py_buffer related functions are now part of the limited API and stable ABI.

.. bpo: 14916 .. date: 2020-09-11-02-50-41 .. nonce: QN1Y03 .. section: C API

Fixed bug in the tokenizer that prevented PyRun_InteractiveOne from parsing from the provided FD.