C API

• bpo-42591 [https://bugs.python.org/issue?@action=redirect&bpo=42591]: Export the Py_FrozenMain() function: fix a Python 3.9.0 regression. Python 3.9 uses -fvisibility=hidden and the function was not exported explicitly and so not exported.

• bpo-32381 [https://bugs.python.org/issue?@action=redirect&bpo=32381]: Remove the private Pyfopen() function which is no longer needed. Use Pywfopen() or Pyfopen_obj() instead. Patch by Victor Stinner.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port resource extension module to module state

• bpo-42111 [https://bugs.python.org/issue?@action=redirect&bpo=42111]: Update the xxlimited module to be a better example of how to use the limited C API.

• bpo-40052 [https://bugs.python.org/issue?@action=redirect&bpo=40052]: Fix an alignment build warning/error in function PyVectorcall_Function(). Patch by Andreas Schneider, Antoine Pitrou and Petr Viktorin.

Python 3.10.0 alpha 3

发布日期: 2020-12-07

安全性

• bpo-40791 [https://bugs.python.org/issue?@action=redirect&bpo=40791]: Add volatile to the accumulator variable in hmac.compare_digest, making constant-time-defeating optimizations less likely.

核心与内置函数

• bpo-42576 [https://bugs.python.org/issue?@action=redirect&bpo=42576]: types.GenericAlias will now raise a TypeError when attempting to initialize with a keyword argument. Previously, this would cause the interpreter to crash if the interpreter was compiled with debug symbols. This does not affect interpreters compiled for release. Patch by Ken Jin.

• bpo-42536 [https://bugs.python.org/issue?@action=redirect&bpo=42536]: Several builtin and standard library types now ensure that their internal result tuples are always tracked by the garbage collector:

  • collections.OrderedDict.items()

  • dict.items()

  • enumerate()

  • functools.reduce()

  • itertools.combinations()

  • itertools.combinations_with_replacement()

  • itertools.permutations()

  • itertools.product()

  • itertools.zip_longest()

  • zip()

之前，它们可能会被前一次垃圾回收取消追踪。 由 Brandt Bucher 提供补丁。

• bpo-42500 [https://bugs.python.org/issue?@action=redirect&bpo=42500]: Improve handling of exceptions near recursion limit. Converts a number of Fatal Errors in RecursionErrors.

• bpo-42246 [https://bugs.python.org/issue?@action=redirect&bpo=42246]: PEP 626: After a return, the f_lineno attribute of a frame is always the last line executed.

• bpo-42435 [https://bugs.python.org/issue?@action=redirect&bpo=42435]: Speed up comparison of bytes objects with non-bytes objects when option -b is specified. Speed up comparison of bytarray objects with non-buffer object.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the _warnings extension module to the multiphase initialization API ( PEP 489 [https://peps.python.org/pep-0489/]). Patch by Victor Stinner.

• bpo-41686 [https://bugs.python.org/issue?@action=redirect&bpo=41686]: On Windows, the SIGINT event, _PyOS_SigintEvent(), is now created even if Python is configured to not install signal handlers (if PyConfig.install_signal_handlers equals to 0, or Py_InitializeEx(0)).

• bpo-42381 [https://bugs.python.org/issue?@action=redirect&bpo=42381]: Allow assignment expressions in set literals and set comprehensions as per PEP 572. Patch by Pablo Galindo.

• bpo-42202 [https://bugs.python.org/issue?@action=redirect&bpo=42202]: Change function parameters annotations internal representation to tuple of strings. Patch provided by Yurii Karabas.

• bpo-42374 [https://bugs.python.org/issue?@action=redirect&bpo=42374]: Fix a regression introduced by the new parser, where an unparenthesized walrus operator was not allowed within generator expressions.

• bpo-42316 [https://bugs.python.org/issue?@action=redirect&bpo=42316]: Allow an unparenthesized walrus in subscript indexes.

• bpo-42349 [https://bugs.python.org/issue?@action=redirect&bpo=42349]: Make sure that the compiler front-end produces a well-formed control flow graph. Be more aggressive in the compiler backend, as it is now safe to do so.

• bpo-42296 [https://bugs.python.org/issue?@action=redirect&bpo=42296]: On Windows, fix a regression in signal handling which prevented to interrupt a program using CTRL+C. The signal handler can be run in a thread different than the Python thread, in which case the test deciding if the thread can handle signals is wrong.

• bpo-42332 [https://bugs.python.org/issue?@action=redirect&bpo=42332]: types.GenericAlias objects can now be the targets of weakrefs.

• bpo-42282 [https://bugs.python.org/issue?@action=redirect&bpo=42282]: Optimise constant subexpressions that appear as part of named expressions (previously the AST optimiser did not descend into named expressions). Patch by Nick Coghlan.

• bpo-42266 [https://bugs.python.org/issue?@action=redirect&bpo=42266]: Fixed a bug with the LOAD_ATTR opcode cache that was not respecting monkey-patching a class-level attribute to make it a descriptor. Patch by Pablo Galindo.

• bpo-40077 [https://bugs.python.org/issue?@action=redirect&bpo=40077]: Convert queue to use heap types.

• bpo-42246 [https://bugs.python.org/issue?@action=redirect&bpo=42246]: Improved accuracy of line tracing events and f_lineno attribute of Frame objects. See PEP 626 for details.

• bpo-40077 [https://bugs.python.org/issue?@action=redirect&bpo=40077]: Convert mmap to use heap types.

• bpo-42233 [https://bugs.python.org/issue?@action=redirect&bpo=42233]: Allow GenericAlias objects to use union type expressions. This allows expressions like list[int] | dict[float, str] where previously a TypeError would have been thrown. This also fixes union type expressions not deduplicating GenericAlias objects. (Contributed by Ken Jin in bpo-42233 [https://bugs.python.org/issue?@action=redirect&bpo=42233].)

• bpo-26131 [https://bugs.python.org/issue?@action=redirect&bpo=26131]: The import system triggers a ImportWarning when it falls back to using load_module().

库

• bpo-5054 [https://bugs.python.org/issue?@action=redirect&bpo=5054]: CGIHTTPRequestHandler.run_cgi() HTTP_ACCEPT improperly parsed. Replace the special purpose getallmatchingheaders with generic get_all method and add relevant tests.

Original Patch by Martin Panter. Modified by Senthil Kumaran.

• bpo-42562 [https://bugs.python.org/issue?@action=redirect&bpo=42562]: Fix issue when dis failed to parse function that has no line numbers. Patch provided by Yurii Karabas.

• bpo-17735 [https://bugs.python.org/issue?@action=redirect&bpo=17735]: inspect.findsource() now raises OSError instead of IndexError when co_lineno of a code object is greater than the file length. This can happen, for example, when a file is edited after it was imported. PR by Irit Katriel.

• bpo-42116 [https://bugs.python.org/issue?@action=redirect&bpo=42116]: Fix handling of trailing comments by inspect.getsource().

• bpo-42532 [https://bugs.python.org/issue?@action=redirect&bpo=42532]: Remove unexpected call of __bool__ when passing a spec_arg argument to a Mock.

• bpo-38200 [https://bugs.python.org/issue?@action=redirect&bpo=38200]: Added itertools.pairwise()

• bpo-41818 [https://bugs.python.org/issue?@action=redirect&bpo=41818]: Fix test_master_read() so that it succeeds on all platforms that either raise OSError or return b"" upon reading from master.

• bpo-42487 [https://bugs.python.org/issue?@action=redirect&bpo=42487]: ChainMap.iter no longer calls getitem on underlying maps

• bpo-42482 [https://bugs.python.org/issue?@action=redirect&bpo=42482]: TracebackException no longer holds a reference to the exception's traceback object. Consequently, instances of TracebackException for equivalent but non-equal exceptions now compare as equal.

• bpo-41818 [https://bugs.python.org/issue?@action=redirect&bpo=41818]: Make test_openpty() avoid unexpected success due to number of rows and/or number of columns being == 0.

• bpo-42392 [https://bugs.python.org/issue?@action=redirect&bpo=42392]: Remove loop parameter from asyncio.subprocess and asyncio.tasks functions. Patch provided by Yurii Karabas.

• bpo-42392 [https://bugs.python.org/issue?@action=redirect&bpo=42392]: Remove loop parameter from asyncio.open_connection and asyncio.start_server functions. Patch provided by Yurii Karabas.

• bpo-28468 [https://bugs.python.org/issue?@action=redirect&bpo=28468]: Add platform.freedesktop_os_release() function to parse freedesktop.org os-release files.

• bpo-42299 [https://bugs.python.org/issue?@action=redirect&bpo=42299]: Removed the formatter module, which was deprecated in Python 3.4. It is somewhat obsolete, little used, and not tested. It was originally scheduled to be removed in Python 3.6, but such removals were delayed until after Python 2.7 EOL. Existing users should copy whatever classes they use into their code. Patch by Donghee Na and and Terry J. Reedy.

• bpo-26131 [https://bugs.python.org/issue?@action=redirect&bpo=26131]: Deprecate zipimport.zipimporter.load_module() in favour of exec_module().

• bpo-41818 [https://bugs.python.org/issue?@action=redirect&bpo=41818]: Updated tests for the pty library. test_basic() has been changed to test_openpty(); this additionally checks if slave termios and slave winsize are being set properly by pty.openpty(). In order to add support for FreeBSD, NetBSD, OpenBSD, and Darwin, this also adds test_master_read(), which demonstrates that pty.spawn() should not depend on an OSError to exit from its copy loop.

• bpo-42392 [https://bugs.python.org/issue?@action=redirect&bpo=42392]: Remove loop parameter from __init__ in all asyncio.locks and asyncio.Queue classes. Patch provided by Yurii Karabas.

• bpo-15450 [https://bugs.python.org/issue?@action=redirect&bpo=15450]: Make filecmp.dircmp respect subclassing. Now the filecmp.dircmp.subdirs behaves as expected when subclassing dircmp.

• bpo-42413 [https://bugs.python.org/issue?@action=redirect&bpo=42413]: The exception socket.timeout is now an alias of TimeoutError.

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: Support signal module on VxWorks.

• bpo-42406 [https://bugs.python.org/issue?@action=redirect&bpo=42406]: We fixed an issue in pickle.whichmodule in which importing multiprocessing could change the how pickle identifies which module an object belongs to, potentially breaking the unpickling of those objects.

• bpo-42403 [https://bugs.python.org/issue?@action=redirect&bpo=42403]: Simplify the importlib external bootstrap code: importlib.bootstrapexternal now uses regular imports to import builtin modules. When it is imported, the builtin __import__() function is already fully working and so can be used to import builtin modules like sys. Patch by Victor Stinner.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Convert _sre module types to heap types (PEP 384). Patch by Erlend E. Aasland.

• bpo-42375 [https://bugs.python.org/issue?@action=redirect&bpo=42375]: subprocess module update for DragonFlyBSD support.

• bpo-41713 [https://bugs.python.org/issue?@action=redirect&bpo=41713]: Port the _signal extension module to the multiphase initialization API ( PEP 489 [https://peps.python.org/pep-0489/]). Patch by Victor Stinner and Mohamed Koubaa.

• bpo-37205 [https://bugs.python.org/issue?@action=redirect&bpo=37205]: time.time(), time.perf_counter() and time.monotonic() functions can no longer fail with a Python fatal error, instead raise a regular Python exception on failure.

• bpo-42328 [https://bugs.python.org/issue?@action=redirect&bpo=42328]: Fixed tkinter.ttk.Style.map(). The function accepts now the representation of the default state as empty sequence (as returned by Style.map()). The structure of the result is now the same on all platform and does not depend on the value of wantobjects.

• bpo-42345 [https://bugs.python.org/issue?@action=redirect&bpo=42345]: Fix various issues with typing.Literal parameter handling (flatten, deduplicate, use type to cache key). Patch provided by Yurii Karabas.

• bpo-37205 [https://bugs.python.org/issue?@action=redirect&bpo=37205]: time.perf_counter() on Windows and time.monotonic() on macOS are now system-wide. Previously, they used an offset computed at startup to reduce the precision loss caused by the float type. Use time.perf_counter_ns() and time.monotonic_ns() added in Python 3.7 to avoid this precision loss.

• bpo-42318 [https://bugs.python.org/issue?@action=redirect&bpo=42318]: Fixed support of non-BMP characters in tkinter on macOS.

• bpo-42350 [https://bugs.python.org/issue?@action=redirect&bpo=42350]: Fix the threading.Thread class at fork: do nothing if the thread is already stopped (ex: fork called at Python exit). Previously, an error was logged in the child process.

• bpo-42333 [https://bugs.python.org/issue?@action=redirect&bpo=42333]: Port _ssl extension module to heap types.

• bpo-42014 [https://bugs.python.org/issue?@action=redirect&bpo=42014]: The onerror callback from shutil.rmtree now receives correct function when os.open fails.

• bpo-42237 [https://bugs.python.org/issue?@action=redirect&bpo=42237]: Fix os.sendfile() on illumos.

• bpo-42308 [https://bugs.python.org/issue?@action=redirect&bpo=42308]: Add threading.__excepthook__ to allow retrieving the original value of threading.excepthook() in case it is set to a broken or a different value. Patch by Mario Corchero.

• bpo-42131 [https://bugs.python.org/issue?@action=redirect&bpo=42131]: Implement PEP 451/spec methods on zipimport.zipimporter: find_spec(), create_module(), and exec_module().

This also allows for the documented deprecation of find_loader(), find_module(), and load_module().

• bpo-41877 [https://bugs.python.org/issue?@action=redirect&bpo=41877]: Mock objects which are not unsafe will now raise an AttributeError if an attribute with the prefix asert, aseert, or assrt is accessed, in addition to this already happening for the prefixes assert or assret.

• bpo-42264 [https://bugs.python.org/issue?@action=redirect&bpo=42264]: sqlite3.OptimizedUnicode has been undocumented and obsolete since Python 3.3, when it was made an alias to str. It is now deprecated, scheduled for removal in Python 3.12.

• bpo-42251 [https://bugs.python.org/issue?@action=redirect&bpo=42251]: Added threading.gettrace() and threading.getprofile() to retrieve the functions set by threading.settrace() and threading.setprofile() respectively. Patch by Mario Corchero.

• bpo-42249 [https://bugs.python.org/issue?@action=redirect&bpo=42249]: Fixed writing binary Plist files larger than 4 GiB.

• bpo-42236 [https://bugs.python.org/issue?@action=redirect&bpo=42236]: On Unix, the os.device_encoding() function now returns 'UTF-8' rather than the device encoding if the Python UTF-8 Mode is enabled.

• bpo-41754 [https://bugs.python.org/issue?@action=redirect&bpo=41754]: webbrowser: Ignore NotADirectoryError when calling xdg-settings.

• bpo-42183 [https://bugs.python.org/issue?@action=redirect&bpo=42183]: Fix a stack overflow error for asyncio Task or Future repr().

在 Task 或 Future 递归返回自身的情形下会导致栈溢出。

• bpo-42140 [https://bugs.python.org/issue?@action=redirect&bpo=42140]: Improve asyncio.wait function to create the futures set just one time.

• bpo-42133 [https://bugs.python.org/issue?@action=redirect&bpo=42133]: Update various modules in the stdlib to fall back on __spec__.loader when __loader__ isn't defined on a module.

• bpo-26131 [https://bugs.python.org/issue?@action=redirect&bpo=26131]: The load_module() methods found in importlib now trigger a DeprecationWarning.

• bpo-39825 [https://bugs.python.org/issue?@action=redirect&bpo=39825]: Windows: Change sysconfig.getconfigvar('EXT_SUFFIX') to the expected full platform_tag.extension format. Previously it was hardcoded to .pyd, now it is compatible with distutils.sysconfig and will result in something like .cp38-win_amd64.pyd. This brings windows into conformance with the other platforms.

• bpo-26389 [https://bugs.python.org/issue?@action=redirect&bpo=26389]: The traceback.format_exception(), traceback.format_exception_only(), and traceback.print_exception() functions can now take an exception object as a positional-only argument.

• bpo-41889 [https://bugs.python.org/issue?@action=redirect&bpo=41889]: Enum: fix regression involving inheriting a multiply inherited enum

• bpo-41861 [https://bugs.python.org/issue?@action=redirect&bpo=41861]: Convert sqlite3 to use heap types (PEP 384). Patch by Erlend E. Aasland.

• bpo-40624 [https://bugs.python.org/issue?@action=redirect&bpo=40624]: Added support for the XPath != operator in xml.etree

• bpo-28850 [https://bugs.python.org/issue?@action=redirect&bpo=28850]: Fix pprint.PrettyPrinter.format() overrides being ignored for contents of small containers. The pprint._safe_repr() function was removed.

• bpo-41625 [https://bugs.python.org/issue?@action=redirect&bpo=41625]: Expose the splice() as os.splice() in the os module. Patch by Pablo Galindo

• bpo-34215 [https://bugs.python.org/issue?@action=redirect&bpo=34215]: Clarify the error message for asyncio.IncompleteReadError when expected is None.

• bpo-41543 [https://bugs.python.org/issue?@action=redirect&bpo=41543]: Add async context manager support for contextlib.nullcontext.

• bpo-21041 [https://bugs.python.org/issue?@action=redirect&bpo=21041]: pathlib.PurePath.parents now supports negative indexing. Patch contributed by Yaroslav Pankovych.

• bpo-41332 [https://bugs.python.org/issue?@action=redirect&bpo=41332]: Added missing connect_accepted_socket() method to asyncio.AbstractEventLoop.

• bpo-12800 [https://bugs.python.org/issue?@action=redirect&bpo=12800]: Extracting a symlink from a tarball should succeed and overwrite the symlink if it already exists. The fix is to remove the existing file or symlink before extraction. Based on patch by Chris AtLee, Jeffrey Kintscher, and Senthil Kumaran.

• bpo-40968 [https://bugs.python.org/issue?@action=redirect&bpo=40968]: urllib.request and http.client now send http/1.1 ALPN extension during TLS handshake when no custom context is supplied.

• bpo-41001 [https://bugs.python.org/issue?@action=redirect&bpo=41001]: Add os.eventfd() to provide a low level interface for Linux's event notification file descriptor.

• bpo-40816 [https://bugs.python.org/issue?@action=redirect&bpo=40816]: Add AsyncContextDecorator to contextlib to support async context manager as a decorator.

• bpo-40550 [https://bugs.python.org/issue?@action=redirect&bpo=40550]: Fix time-of-check/time-of-action issue in subprocess.Popen.send_signal.

• bpo-39411 [https://bugs.python.org/issue?@action=redirect&bpo=39411]: Add an is_async identifier to pyclbr's Function objects. Patch by Batuhan Taskaya

• bpo-35498 [https://bugs.python.org/issue?@action=redirect&bpo=35498]: Add slice support to pathlib.PurePath.parents.

文档

• bpo-42238 [https://bugs.python.org/issue?@action=redirect&bpo=42238]: Tentative to deprecate make suspicious by first removing it from the CI and documentation builds, but keeping it around for manual uses.

• bpo-42153 [https://bugs.python.org/issue?@action=redirect&bpo=42153]: Fix the URL for the IMAP protocol documents.

• bpo-41028 [https://bugs.python.org/issue?@action=redirect&bpo=41028]: Language and version switchers, previously maintained in every cpython branches, are now handled by docsbuild-script.

测试

• bpo-41473 [https://bugs.python.org/issue?@action=redirect&bpo=41473]: Re-enable test_gdb on gdb 9.2 and newer: https://bugzilla.redhat.com/show_bug.cgi?id=1866884 bug is fixed in gdb 10.1.

• bpo-42553 [https://bugs.python.org/issue?@action=redirect&bpo=42553]: Fix test_asyncio.test_call_later() race condition: don't measure asyncio performance in the call_later() unit test. The test failed randomly on the CI.

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: Fix test_netrc on VxWorks: create temporary directories using temp_cwd().

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: skip test_getaddrinfo_ipv6_scopeid_symbolic and test_getnameinfo_ipv6_scopeid_symbolic on VxWorks

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: skip test_test of test_mailcap on VxWorks

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: add shell requirement for test_pipes

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: skip some tests related to fifo on VxWorks

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: Fix test_doctest.py failures for VxWorks.

• bpo-40754 [https://bugs.python.org/issue?@action=redirect&bpo=40754]: Include _testinternalcapi module in Windows installer for test suite

• bpo-41561 [https://bugs.python.org/issue?@action=redirect&bpo=41561]: test_ssl: skip test_min_max_version_mismatch when TLS 1.0 is not available

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: Fix os module failures for VxWorks RTOS.

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: Fix fifo test cases for VxWorks RTOS.

构建

• bpo-31904 [https://bugs.python.org/issue?@action=redirect&bpo=31904]: remove libnet dependency from detect_socket() for VxWorks

• bpo-42398 [https://bugs.python.org/issue?@action=redirect&bpo=42398]: Fix a race condition in "make regen-all" when make -jN option is used to run jobs in parallel. The clinic.py script now only use atomic write to write files. Moveover, generated files are now left unchanged if the content does not change, to not change the file modification time.

• bpo-41617 [https://bugs.python.org/issue?@action=redirect&bpo=41617]: Fix building pycore_bitutils.h internal header on old clang version without __builtin_bswap16() (ex: Xcode 4.6.3 on Mac OS X 10.7). Patch by Joshua Root and Victor Stinner.

• bpo-38823 [https://bugs.python.org/issue?@action=redirect&bpo=38823]: It is no longer possible to build the _ctypes extension module without wchar_t type: remove CTYPES_UNICODE macro. Anyway, the wchar_t type is required to build Python. Patch by Victor Stinner.

• bpo-42087 [https://bugs.python.org/issue?@action=redirect&bpo=42087]: Support was removed for AIX 5.3 and below. See bpo-40680 [https://bugs.python.org/issue?@action=redirect&bpo=40680].

• bpo-40998 [https://bugs.python.org/issue?@action=redirect&bpo=40998]: Addressed three compiler warnings found by undefined behavior sanitizer (ubsan).

Windows

• bpo-42120 [https://bugs.python.org/issue?@action=redirect&bpo=42120]: Remove macro definition of copysign (to _copysign) in headers.

• bpo-38506 [https://bugs.python.org/issue?@action=redirect&bpo=38506]: The Windows launcher now properly handles Python 3.10 when listing installed Python versions.

macOS

• bpo-42504 [https://bugs.python.org/issue?@action=redirect&bpo=42504]: Fix build on macOS Big Sur when MACOSX_DEPLOYMENT_TARGET=11

• bpo-41116 [https://bugs.python.org/issue?@action=redirect&bpo=41116]: Ensure distutils.unixxcompiler.find_library_file can find system provided libraries on macOS 11.

• bpo-41100 [https://bugs.python.org/issue?@action=redirect&bpo=41100]: Add support for macOS 11 and Apple Silicon systems.

It is now possible to build "Universal 2" binaries using "—enable-universalsdk —with-universal-archs=universal2".

Binaries build on later macOS versions can be deployed back to older versions (tested up to macOS 10.9), when using the correct deployment target. This is tested using Xcode 11 and later.

• bpo-42232 [https://bugs.python.org/issue?@action=redirect&bpo=42232]: Added Darwin specific madvise options to mmap module.

• bpo-38443 [https://bugs.python.org/issue?@action=redirect&bpo=38443]: The --enable-universalsdk and --with-universal-archs options for the configure script now check that the specified architectures can be used.

IDLE

• bpo-42508 [https://bugs.python.org/issue?@action=redirect&bpo=42508]: Keep IDLE running on macOS. Remove obsolete workaround that prevented running files with shortcuts when using new universal2 installers built on macOS 11.

• bpo-42426 [https://bugs.python.org/issue?@action=redirect&bpo=42426]: Fix reporting offset of the RE error in searchengine.

• bpo-42415 [https://bugs.python.org/issue?@action=redirect&bpo=42415]: Get docstrings for IDLE calltips more often by using inspect.getdoc.

工具/示例

• bpo-42212 [https://bugs.python.org/issue?@action=redirect&bpo=42212]: The smelly.py script now also checks the Python dynamic library and extension modules, not only the Python static library. Make also the script more verbose: explain what it does.

• bpo-36310 [https://bugs.python.org/issue?@action=redirect&bpo=36310]: Allow Tools/i18n/pygettext.py to detect calls to gettext in fstrings.

C API

• bpo-42423 [https://bugs.python.org/issue?@action=redirect&bpo=42423]: The PyType_FromSpecWithBases() and PyType_FromModuleAndSpec() functions now accept a single class as the bases argument.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port select extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port _posixsubprocess extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port _posixshmem extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/])

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port _struct extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/])

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port spwd extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/])

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port gc extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/])

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port _queue extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/])

• bpo-39573 [https://bugs.python.org/issue?@action=redirect&bpo=39573]: Convert Py_TYPE() and Py_SIZE() back to macros to allow using them as an l-value. Many third party C extension modules rely on the ability of using Py_TYPE() and Py_SIZE() to set an object type and size: Py_TYPE(obj) = type; and Py_SIZE(obj) = size;.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port symtable extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/])

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port grp and pwd extension modules to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/])

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port _random extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/])

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port _hashlib extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/])

• bpo-41713 [https://bugs.python.org/issue?@action=redirect&bpo=41713]: Removed the undocumented PyOS_InitInterrupts() function. Initializing Python already implicitly installs signal handlers: see PyConfig.install_signal_handlers. Patch by Victor Stinner.

• bpo-40170 [https://bugs.python.org/issue?@action=redirect&bpo=40170]: The Py_TRASHCAN_BEGIN macro no longer accesses PyTypeObject attributes, but now can get the condition by calling the new private PyTrashcond() function which hides implementation details.

• bpo-42260 [https://bugs.python.org/issue?@action=redirect&bpo=42260]: Py_GetPath(), Py_GetPrefix(), Py_GetExecPrefix(), Py_GetProgramFullPath(), Py_GetPythonHome() and Py_GetProgramName() functions now return NULL if called before Py_Initialize() (before Python is initialized). Use the new Python Initialization Configuration API to get the Python Path Configuration.. Patch by Victor Stinner.

• bpo-42260 [https://bugs.python.org/issue?@action=redirect&bpo=42260]: The PyConfig_Read() function now only parses PyConfig.argv arguments once: PyConfig.parse_argv is set to 2 after arguments are parsed. Since Python arguments are strippped from PyConfig.argv, parsing arguments twice would parse the application options as Python options.

• bpo-42262 [https://bugs.python.org/issue?@action=redirect&bpo=42262]: Added Py_NewRef() and Py_XNewRef() functions to increment the reference count of an object and return the object. Patch by Victor Stinner.

• bpo-42260 [https://bugs.python.org/issue?@action=redirect&bpo=42260]: When Py_Initialize() is called twice, the second call now updates more sys attributes for the configuration, rather than only sys.argv. Patch by Victor Stinner.

• bpo-41832 [https://bugs.python.org/issue?@action=redirect&bpo=41832]: The PyType_FromModuleAndSpec() function now accepts NULL tp_doc slot.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Added PyModule_AddObjectRef() function: similar to PyModule_AddObject() but don't steal a reference to the value on success. Patch by Victor Stinner.

• bpo-42171 [https://bugs.python.org/issue?@action=redirect&bpo=42171]: The METH_FASTCALL calling convention is added to the limited API. The functions PyModule_AddType(), PyType_FromModuleAndSpec(), PyType_GetModule() and PyType_GetModuleState() are added to the limited API on Windows.

• bpo-42085 [https://bugs.python.org/issue?@action=redirect&bpo=42085]: Add dedicated entry to PyAsyncMethods for sending values

• bpo-41073 [https://bugs.python.org/issue?@action=redirect&bpo=41073]: PyType_GetSlot() can now accept static types.

• bpo-30459 [https://bugs.python.org/issue?@action=redirect&bpo=30459]: PyList_SET_ITEM(), PyTuple_SET_ITEM() and PyCell_SET() macros can no longer be used as l-value or r-value. For example, x = PyList_SET_ITEM(a, b, c) and PyList_SET_ITEM(a, b, c) = x now fail with a compiler error. It prevents bugs like if (PyList_SET_ITEM (a, b, c) < 0) … test. Patch by Zackery Spytz and Victor Stinner.

Python 3.10.0 alpha 2

发布日期: 2020-11-03

安全性

• bpo-42103 [https://bugs.python.org/issue?@action=redirect&bpo=42103]: Prevented potential DoS attack via CPU and RAM exhaustion when processing malformed Apple Property List files in binary format.

• bpo-42051 [https://bugs.python.org/issue?@action=redirect&bpo=42051]: The plistlib module no longer accepts entity declarations in XML plist files to avoid XML vulnerabilities. This should not affect users as entity declarations are not used in regular plist files.

核心与内置函数

• bpo-42236 [https://bugs.python.org/issue?@action=redirect&bpo=42236]: If the nl_langinfo(CODESET) function returns an empty string, Python now uses UTF-8 as the filesystem encoding. Patch by Victor Stinner.

• bpo-42218 [https://bugs.python.org/issue?@action=redirect&bpo=42218]: Fixed a bug in the PEG parser that was causing crashes in debug mode. Now errors are checked in left-recursive rules to avoid cases where such errors do not get handled in time and appear as long-distance crashes in other places.

• bpo-42214 [https://bugs.python.org/issue?@action=redirect&bpo=42214]: Fixed a possible crash in the PEG parser when checking for the '!=' token in the barryasflufl rule. Patch by Pablo Galindo.

• bpo-42206 [https://bugs.python.org/issue?@action=redirect&bpo=42206]: Propagate and raise the errors caused by PyAST_Validate() in the parser.

• bpo-41796 [https://bugs.python.org/issue?@action=redirect&bpo=41796]: The ast module internal state is now per interpreter. Patch by Victor Stinner.

• bpo-42143 [https://bugs.python.org/issue?@action=redirect&bpo=42143]: Fix handling of errors during creation of PyFunctionObject, which resulted in operations on uninitialized memory. Patch by Yonatan Goldschmidt.

• bpo-41659 [https://bugs.python.org/issue?@action=redirect&bpo=41659]: Fix a bug in the parser, where a curly brace following a primary didn't fail immediately. This led to invalid expressions like a {b} to throw a SyntaxError with a wrong offset, or invalid expressions ending with a curly brace like a { to not fail immediately in the REPL.

• bpo-42150 [https://bugs.python.org/issue?@action=redirect&bpo=42150]: Fix possible buffer overflow in the new parser when checking for continuation lines. Patch by Pablo Galindo.

• bpo-42123 [https://bugs.python.org/issue?@action=redirect&bpo=42123]: Run the parser two times. On the first run, disable all the rules that only generate better error messages to gain performance. If there's a parse failure, run the parser a second time with those enabled.

• bpo-42093 [https://bugs.python.org/issue?@action=redirect&bpo=42093]: The LOAD_ATTR instruction now uses new "per opcode cache" mechanism and it is about 36% faster now. Patch by Pablo Galindo and Yury Selivanov.

• bpo-42030 [https://bugs.python.org/issue?@action=redirect&bpo=42030]: Support for the legacy AIX-specific shared library loading support has been removed. All versions of AIX since 4.3 have supported and defaulted to using the common Unix mechanism instead.

• bpo-41984 [https://bugs.python.org/issue?@action=redirect&bpo=41984]: The garbage collector now tracks all user-defined classes. Patch by Brandt Bucher.

• bpo-41993 [https://bugs.python.org/issue?@action=redirect&bpo=41993]: Fixed potential issues with removing not completely initialized module from sys.modules when import fails.

• bpo-41979 [https://bugs.python.org/issue?@action=redirect&bpo=41979]: Star-unpacking is now allowed for with item's targets in the PEG parser.

• bpo-41974 [https://bugs.python.org/issue?@action=redirect&bpo=41974]: Removed special methods __int__, __float__, __floordiv__, __mod__, __divmod__, __rfloordiv__, __rmod__ and __rdivmod__ of the complex class. They always raised a TypeError.

• bpo-41902 [https://bugs.python.org/issue?@action=redirect&bpo=41902]: Micro optimization when compute sq_item and mp_subscript of range. Patch by Donghee Na.

• bpo-41894 [https://bugs.python.org/issue?@action=redirect&bpo=41894]: When loading a native module and a load failure occurs, prevent a possible UnicodeDecodeError when not running in a UTF-8 locale by decoding the load error message using the current locale's encoding.

• bpo-41902 [https://bugs.python.org/issue?@action=redirect&bpo=41902]: Micro optimization for range.index if step is 1. Patch by Donghee Na.

• bpo-41435 [https://bugs.python.org/issue?@action=redirect&bpo=41435]: Add sys._current_exceptions() function to retrieve a dictionary mapping each thread's identifier to the topmost exception currently active in that thread at the time the function is called.

• bpo-38605 [https://bugs.python.org/issue?@action=redirect&bpo=38605]: Enable from __future__ import annotations ( PEP 563 [https://peps.python.org/pep-0563/]) by default. The values found in __annotations__ dicts are now strings, for example {"x": "int"} instead of {"x": int}.

库

• bpo-35455 [https://bugs.python.org/issue?@action=redirect&bpo=35455]: On Solaris, thread_time() is now implemented with gethrvtime() because clock_gettime(CLOCK_THREAD_CPUTIME_ID) is not always available. Patch by Jakub Kulik.

• bpo-42233 [https://bugs.python.org/issue?@action=redirect&bpo=42233]: The repr() of typing types containing Generic Alias Types previously did not show the parameterized types in the GenericAlias. They have now been changed to do so.

• bpo-29566 [https://bugs.python.org/issue?@action=redirect&bpo=29566]: binhex.binhex() consistently writes macOS 9 line endings.

• bpo-26789 [https://bugs.python.org/issue?@action=redirect&bpo=26789]: The logging.FileHandler class now keeps a reference to the builtin open() function to be able to open or reopen the file during Python finalization. Fix errors like: NameError: name 'open' is not defined. Patch by Victor Stinner.

• bpo-42157 [https://bugs.python.org/issue?@action=redirect&bpo=42157]: Removed the unicodedata.ucnhash_CAPI attribute which was an internal PyCapsule object. The related private PyUnicodeName_CAPI structure was moved to the internal C API. Patch by Victor Stinner.

• bpo-42157 [https://bugs.python.org/issue?@action=redirect&bpo=42157]: Convert the unicodedata extension module to the multiphase initialization API ( PEP 489 [https://peps.python.org/pep-0489/]) and convert the unicodedata.UCD static type to a heap type. Patch by Mohamed Koubaa and Victor Stinner.

• bpo-42146 [https://bugs.python.org/issue?@action=redirect&bpo=42146]: Fix memory leak in subprocess.Popen() in case an uid (gid) specified in user (group, extra_groups) overflows uid_t (gid_t).

• bpo-42103 [https://bugs.python.org/issue?@action=redirect&bpo=42103]: InvalidFileException and RecursionError are now the only errors caused by loading malformed binary Plist file (previously ValueError and TypeError could be raised in some specific cases).

• bpo-41490 [https://bugs.python.org/issue?@action=redirect&bpo=41490]: In importlib.resources, .path method is more aggressive about releasing handles to zipfile objects early, enabling use-cases like certifi to leave the context open but delete the underlying zip file.

• bpo-41052 [https://bugs.python.org/issue?@action=redirect&bpo=41052]: Pickling heap types implemented in C with protocols 0 and 1 raises now an error instead of producing incorrect data.

• bpo-42089 [https://bugs.python.org/issue?@action=redirect&bpo=42089]: In importlib.metadata.PackageNotFoundError, make reference to the package metadata being missing to improve the user experience.

• bpo-41491 [https://bugs.python.org/issue?@action=redirect&bpo=41491]: plistlib: fix parsing XML plists with hexadecimal integer values

• bpo-42065 [https://bugs.python.org/issue?@action=redirect&bpo=42065]: Fix an incorrectly formatted error from codecs.charmapdecode() when called with a mapped value outside the range of valid Unicode code points. PR by Max Bernstein.

• bpo-41966 [https://bugs.python.org/issue?@action=redirect&bpo=41966]: Fix pickling pure Python datetime.time subclasses. Patch by Dean Inwood.

• bpo-19270 [https://bugs.python.org/issue?@action=redirect&bpo=19270]: sched.scheduler.cancel() will now cancel the correct event, if two events with same priority are scheduled for the same time. Patch by Bar Harel.

• bpo-28660 [https://bugs.python.org/issue?@action=redirect&bpo=28660]: textwrap.wrap() now attempts to break long words after hyphens when break_long_words=True and break_on_hyphens=True.

• bpo-35823 [https://bugs.python.org/issue?@action=redirect&bpo=35823]: Use vfork() instead of fork() for subprocess.Popen() on Linux to improve performance in cases where it is deemed safe.

• bpo-42043 [https://bugs.python.org/issue?@action=redirect&bpo=42043]: Add support for zipfile.Path inheritance. zipfile.Path.is_file() now returns False for nonexistent names. zipfile.Path objects now expose a .filename attribute and rely on that to resolve .name and .parent when the Path object is at the root of the zipfile.

• bpo-42021 [https://bugs.python.org/issue?@action=redirect&bpo=42021]: Fix possible ref leaks in sqlite3 module init.

• bpo-39101 [https://bugs.python.org/issue?@action=redirect&bpo=39101]: Fixed tests using IsolatedAsyncioTestCase from hanging on BaseExceptions.

• bpo-41976 [https://bugs.python.org/issue?@action=redirect&bpo=41976]: Fixed a bug that was causing ctypes.util.find_library() to return None when triying to locate a library in an environment when gcc>=9 is available and ldconfig is not. Patch by Pablo Galindo

• bpo-41943 [https://bugs.python.org/issue?@action=redirect&bpo=41943]: Fix bug where TestCase.assertLogs doesn't correctly filter messages by level.

• bpo-41923 [https://bugs.python.org/issue?@action=redirect&bpo=41923]: Implement PEP 613 [https://peps.python.org/pep-0613/], introducing typing.TypeAlias annotation.

• bpo-41905 [https://bugs.python.org/issue?@action=redirect&bpo=41905]: A new function in abc: update_abstractmethods to re-calculate an abstract class's abstract status. In addition, dataclass has been changed to call this function.

• bpo-23706 [https://bugs.python.org/issue?@action=redirect&bpo=23706]: Added newline parameter to pathlib.Path.write_text().

• bpo-41876 [https://bugs.python.org/issue?@action=redirect&bpo=41876]: Tkinter font class repr uses font name

• bpo-41831 [https://bugs.python.org/issue?@action=redirect&bpo=41831]: str() for the type attribute of the tkinter.Event object always returns now the numeric code returned by Tk instead of the name of the event type.

• bpo-39337 [https://bugs.python.org/issue?@action=redirect&bpo=39337]: encodings.normalize_encoding() now ignores nonASCII characters.

• bpo-41747 [https://bugs.python.org/issue?@action=redirect&bpo=41747]: Ensure all methods that generated from dataclasses.dataclass() objects now have the proper __qualname__ attribute referring to the class they belong to. Patch by Batuhan Taskaya.

• bpo-30681 [https://bugs.python.org/issue?@action=redirect&bpo=30681]: Handle exceptions caused by unparsable date headers when using email "default" policy. Patch by Tim Bell, Georges Toth

• bpo-41586 [https://bugs.python.org/issue?@action=redirect&bpo=41586]: Add F_SETPIPE_SZ and F_GETPIPE_SZ to fcntl module. Allow setting pipesize on subprocess.Popen.

• bpo-41229 [https://bugs.python.org/issue?@action=redirect&bpo=41229]: Add contextlib.aclosing for deterministic cleanup of async generators which is analogous to contextlib.closing for non-async generators. Patch by Joongi Kim and John Belmonte.

• bpo-16396 [https://bugs.python.org/issue?@action=redirect&bpo=16396]: Allow ctypes.wintypes to be imported on non-Windows systems.

• bpo-4356 [https://bugs.python.org/issue?@action=redirect&bpo=4356]: Add a key function to the bisect module.

• bpo-40592 [https://bugs.python.org/issue?@action=redirect&bpo=40592]: shutil.which() now ignores empty entries in PATHEXT instead of treating them as a match.

• bpo-40492 [https://bugs.python.org/issue?@action=redirect&bpo=40492]: Fix --outfile for cProfile / profile not writing the output file in the original directory when the program being profiled changes the working directory. PR by Anthony Sottile.

• bpo-34204 [https://bugs.python.org/issue?@action=redirect&bpo=34204]: The shelve module now uses pickle.DEFAULT_PROTOCOL by default instead of pickle protocol 3.

• bpo-27321 [https://bugs.python.org/issue?@action=redirect&bpo=27321]: Fixed KeyError exception when flattening an email to a string attempts to replace a nonexistent Content-Transfer-Encoding header.

• bpo-38976 [https://bugs.python.org/issue?@action=redirect&bpo=38976]: The http.cookiejar module now supports the parsing of cookies in CURL-style cookiejar files through MozillaCookieJar on all platforms. Previously, such cookie entries would be silently ignored when loading a cookiejar with such entries.

Additionally, the HTTP Only attribute is persisted in the object, and will be correctly written to file if the MozillaCookieJar object is subsequently dumped.

文档

• bpo-42061 [https://bugs.python.org/issue?@action=redirect&bpo=42061]: Document format functionality for IP addresses.

• bpo-41910 [https://bugs.python.org/issue?@action=redirect&bpo=41910]: Document the default implementation of object.__eq__.

• bpo-42010 [https://bugs.python.org/issue?@action=redirect&bpo=42010]: Clarify that subscription expressions are also valid for certain classes and types in the standard library, and for user-defined classes and types if the classmethod __class_getitem__() is provided.

• bpo-41805 [https://bugs.python.org/issue?@action=redirect&bpo=41805]: Documented generic alias type and types.GenericAlias. Also added an entry in glossary for generic types.

• bpo-39693 [https://bugs.python.org/issue?@action=redirect&bpo=39693]: Fix tarfile's extractfile documentation

• bpo-39416 [https://bugs.python.org/issue?@action=redirect&bpo=39416]: Document some restrictions on the default string representations of numeric classes.

测试

• bpo-41739 [https://bugs.python.org/issue?@action=redirect&bpo=41739]: Fix test_logging.test_race_betweensettarget_and_flush(): the test now waits until all threads complete to avoid leaking running threads.

• bpo-41970 [https://bugs.python.org/issue?@action=redirect&bpo=41970]: Avoid a test failure in test_lib2to3 if the module has already imported at the time the test executes. Patch by Pablo Galindo.

• bpo-41944 [https://bugs.python.org/issue?@action=redirect&bpo=41944]: Tests for CJK codecs no longer call eval() on content received via HTTP.

• bpo-41306 [https://bugs.python.org/issue?@action=redirect&bpo=41306]: Fixed a failure in test_tk.test_widgets.ScaleTest happening when executing the test with Tk 8.6.10.

构建

• bpo-38980 [https://bugs.python.org/issue?@action=redirect&bpo=38980]: Add -fno-semantic-interposition to both the compile and link line when building with --enable-optimizations. Patch by Victor Stinner and Pablo Galindo.

Windows

• bpo-38439 [https://bugs.python.org/issue?@action=redirect&bpo=38439]: Updates the icons for IDLE in the Windows Store package.

• bpo-38252 [https://bugs.python.org/issue?@action=redirect&bpo=38252]: Use 8-byte step to detect ASCII sequence in 64-bit Windows build.

• bpo-39107 [https://bugs.python.org/issue?@action=redirect&bpo=39107]: Update Tcl and Tk to 8.6.10 in Windows installer.

• bpo-41557 [https://bugs.python.org/issue?@action=redirect&bpo=41557]: Update Windows installer to use SQLite 3.33.0.

• bpo-38324 [https://bugs.python.org/issue?@action=redirect&bpo=38324]: Avoid Unicode errors when accessing certain locale data on Windows.

macOS

• bpo-41471 [https://bugs.python.org/issue?@action=redirect&bpo=41471]: Ignore invalid prefix lengths in system proxy excludes.

IDLE

• bpo-33987 [https://bugs.python.org/issue?@action=redirect&bpo=33987]: Mostly finish using ttk widgets, mainly for editor, settings, and searches. Some patches by Mark Roseman.

• bpo-40511 [https://bugs.python.org/issue?@action=redirect&bpo=40511]: Typing opening and closing parentheses inside the parentheses of a function call will no longer cause unnecessary "flashing" off and on of an existing open calltip, e.g. when typed in a string literal.

• bpo-38439 [https://bugs.python.org/issue?@action=redirect&bpo=38439]: Add a 256×256 pixel IDLE icon to the Windows .ico file. Created by Andrew Clover. Remove the low-color gif variations from the .ico file.

C API

• bpo-42157 [https://bugs.python.org/issue?@action=redirect&bpo=42157]: The private PyUnicodeName_CAPI structure of the PyCapsule API unicodedata.ucnhash_CAPI has been moved to the internal C API. Patch by Victor Stinner.

• bpo-42015 [https://bugs.python.org/issue?@action=redirect&bpo=42015]: Fix potential crash in deallocating method objects when dynamically allocated PyMethodDef's lifetime is managed through the self argument of a PyCFunction.

• bpo-40423 [https://bugs.python.org/issue?@action=redirect&bpo=40423]: The subprocess module and os.closerange will now use the close_range(low, high, flags) syscall when it is available for more efficient closing of ranges of descriptors.

• bpo-41845 [https://bugs.python.org/issue?@action=redirect&bpo=41845]: PyObject_GenericGetDict() is available again in the limited API when targeting 3.10 or later.

• bpo-40422 [https://bugs.python.org/issue?@action=redirect&bpo=40422]: Add Pycloserange function to provide performant closing of a range of file descriptors.

• bpo-41986 [https://bugs.python.org/issue?@action=redirect&bpo=41986]: Py_FileSystemDefaultEncodeErrors and Py_UTF8Mode are available again in limited API.

• bpo-41756 [https://bugs.python.org/issue?@action=redirect&bpo=41756]: Add PyIter_Send function to allow sending value into generator/coroutine/iterator without raising StopIteration exception to signal return.

• bpo-41784 [https://bugs.python.org/issue?@action=redirect&bpo=41784]: Added PyUnicode_AsUTF8AndSize to the limited C API.

Python 3.10.0 alpha 1

Release date: 2020-10-05

安全性

• bpo-41304 [https://bugs.python.org/issue?@action=redirect&bpo=41304]: Fixes python3x._pth being ignored on Windows, caused by the fix for bpo-29778 [https://bugs.python.org/issue?@action=redirect&bpo=29778] ( CVE 2020-15801 [https://www.cve.org/CVERecord?id=CVE-2020-15801]).

• bpo-41162 [https://bugs.python.org/issue?@action=redirect&bpo=41162]: Audit hooks are now cleared later during finalization to avoid missing events.

• bpo-29778 [https://bugs.python.org/issue?@action=redirect&bpo=29778]: Ensure python3.dll is loaded from correct locations when Python is embedded ( CVE 2020-15523 [https://www.cve.org/CVERecord?id=CVE-2020-15523]).

• bpo-41004 [https://bugs.python.org/issue?@action=redirect&bpo=41004]: The hash() methods of ipaddress.IPv4Interface and ipaddress.IPv6Interface incorrectly generated constant hash values of 32 and 128 respectively. This resulted in always causing hash collisions. The fix uses hash() to generate hash values for the tuple of (address, mask length, network address).

• bpo-39603 [https://bugs.python.org/issue?@action=redirect&bpo=39603]: Prevent http header injection by rejecting control characters in http.client.putrequest(…).

核心与内置函数

• bpo-41909 [https://bugs.python.org/issue?@action=redirect&bpo=41909]: Fixed stack overflow in issubclass() and isinstance() when getting the __bases__ attribute leads to infinite recursion.

• bpo-41922 [https://bugs.python.org/issue?@action=redirect&bpo=41922]: Speed up calls to reversed() by using the PEP 590 [https://peps.python.org/pep-0590/] vectorcall calling convention. Patch by Donghee Na.

• bpo-41873 [https://bugs.python.org/issue?@action=redirect&bpo=41873]: Calls to float() are now faster due to the vectorcall calling convention. Patch by Dennis Sweeney.

• bpo-41870 [https://bugs.python.org/issue?@action=redirect&bpo=41870]: Speed up calls to bool() by using the PEP 590 [https://peps.python.org/pep-0590/] vectorcall calling convention. Patch by Donghee Na.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the _bisect module to the multiphase initialization API ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-39934 [https://bugs.python.org/issue?@action=redirect&bpo=39934]: Correctly count control blocks in 'except' in compiler. Ensures that a syntax error, rather a fatal error, occurs for deeply nested, named exception handlers.

• bpo-41780 [https://bugs.python.org/issue?@action=redirect&bpo=41780]: Fix __dir__() of types.GenericAlias. Patch by Batuhan Taskaya.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the _lsprof extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the cmath extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the _scproxy extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the termios extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Convert the _sha256 extension module types to heap types.

• bpo-41690 [https://bugs.python.org/issue?@action=redirect&bpo=41690]: Fix a possible stack overflow in the parser when parsing functions and classes with a huge amount of arguments. Patch by Pablo Galindo.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the _overlapped extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the cursespanel extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the _opcode extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-41681 [https://bugs.python.org/issue?@action=redirect&bpo=41681]: Fixes the wrong error description in the error raised by using 2 , in format string in fstring and str.format().

• bpo-41675 [https://bugs.python.org/issue?@action=redirect&bpo=41675]: The implementation of signal.siginterrupt() now uses sigaction() (if it is available in the system) instead of the deprecated siginterrupt(). Patch by Pablo Galindo.

• bpo-41670 [https://bugs.python.org/issue?@action=redirect&bpo=41670]: Prevent line trace being skipped on platforms not compiled with USE_COMPUTED_GOTOS. Fixes issue where some lines nested within a try-except block were not being traced on Windows.

• bpo-41654 [https://bugs.python.org/issue?@action=redirect&bpo=41654]: Fix a crash that occurred when destroying subclasses of MemoryError. Patch by Pablo Galindo.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the zlib extension module to multiphase initialization ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-41631 [https://bugs.python.org/issue?@action=redirect&bpo=41631]: The _ast module uses again a global state. Using a module state per module instance is causing subtle practical problems. For example, the Mercurial project replaces the __import__() function to implement lazy import, whereas Python expected that import _ast always return a fully initialized _ast module.

• bpo-40077 [https://bugs.python.org/issue?@action=redirect&bpo=40077]: Convert _operator to use PyType_FromSpec().

• bpo-1653741 [https://bugs.python.org/issue?@action=redirect&bpo=1653741]: Port _sha3 to multiphase init. Convert static types to heap types.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the _blake2 extension module to the multiphase initialization API ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-41533 [https://bugs.python.org/issue?@action=redirect&bpo=41533]: Free the stack allocated in va_build_stack if do_mkstack fails and the stack is not a small_stack.

• bpo-41531 [https://bugs.python.org/issue?@action=redirect&bpo=41531]: Fix a bug that was dropping keys when compiling dict literals with more than 0xFFFF elements. Patch by Pablo Galindo.

• bpo-41525 [https://bugs.python.org/issue?@action=redirect&bpo=41525]: The output of python --help contains now only ASCII characters.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the _sha1, _sha512, and _md5 extension modules to multiphase initialization API ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-41431 [https://bugs.python.org/issue?@action=redirect&bpo=41431]: Optimize dict_merge() for copying dict (e.g. dict(d) and {}.update(d)).

• bpo-41428 [https://bugs.python.org/issue?@action=redirect&bpo=41428]: Implement PEP 604. This supports (int | str) etc. in place of Union[str, int].

• bpo-41340 [https://bugs.python.org/issue?@action=redirect&bpo=41340]: Removed fallback implementation for strdup.

• bpo-38156 [https://bugs.python.org/issue?@action=redirect&bpo=38156]: Handle interrupts that come after EOF correctly in PyOS_StdioReadline.

• bpo-41342 [https://bugs.python.org/issue?@action=redirect&bpo=41342]: round() with integer argument is now faster (9—60%).

• bpo-41334 [https://bugs.python.org/issue?@action=redirect&bpo=41334]: Constructors str(), bytes() and bytearray() are now faster (around 30—40% for small objects).

• bpo-41295 [https://bugs.python.org/issue?@action=redirect&bpo=41295]: Resolve a regression in CPython 3.8.4 where defining "setattr" in a multi-inheritance setup and calling up the hierarchy chain could fail if builtins/extension types were involved in the base types.

• bpo-41323 [https://bugs.python.org/issue?@action=redirect&bpo=41323]: Bytecode optimizations are performed directly on the control flow graph. This will result in slightly more compact code objects in some circumstances.

• bpo-41247 [https://bugs.python.org/issue?@action=redirect&bpo=41247]: Always cache the running loop holder when running asyncio.set_running_loop.

• bpo-41252 [https://bugs.python.org/issue?@action=redirect&bpo=41252]: Fix incorrect refcounting in _ssl.c's _servername_callback().

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port multiprocessing to multiphase initialization

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port winapi to multiphase initialization

• bpo-41215 [https://bugs.python.org/issue?@action=redirect&bpo=41215]: Use non-NULL default values in the PEG parser keyword list to overcome a bug that was preventing Python from being properly compiled when using the XLC compiler. Patch by Pablo Galindo.

• bpo-41218 [https://bugs.python.org/issue?@action=redirect&bpo=41218]: Python 3.8.3 had a regression where compiling with ast.PyCF_ALLOW_TOP_LEVEL_AWAIT would aggressively mark list comprehension with CO_COROUTINE. Now only list comprehension making use of async/await will tagged as so.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port faulthandler to multiphase initialization.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port sha256 to multiphase initialization

• bpo-41175 [https://bugs.python.org/issue?@action=redirect&bpo=41175]: Guard against a NULL pointer dereference within bytearrayobject triggered by the bytearray() + bytearray() operation.

• bpo-41100 [https://bugs.python.org/issue?@action=redirect&bpo=41100]: add arm64 to the allowable Mac OS arches in mpdecimal.h

• bpo-41094 [https://bugs.python.org/issue?@action=redirect&bpo=41094]: Fix decoding errors with audit when open files with nonASCII names on non-UTF-8 locale.

• bpo-39960 [https://bugs.python.org/issue?@action=redirect&bpo=39960]: The "hackcheck" that prevents sneaking around a type's setattr() by calling the superclass method was rewritten to allow C implemented heap types.

• bpo-41084 [https://bugs.python.org/issue?@action=redirect&bpo=41084]: Prefix the error message with 'fstring: ', when parsing an fstring expression which throws a SyntaxError.

• bpo-40521 [https://bugs.python.org/issue?@action=redirect&bpo=40521]: Empty frozensets are no longer singletons.

• bpo-41076 [https://bugs.python.org/issue?@action=redirect&bpo=41076]: Prefeed the parser with the location of the fstring expression, not the fstring itself, which allows us to skip the shifting of the AST node locations after the parsing is completed.

• bpo-41056 [https://bugs.python.org/issue?@action=redirect&bpo=41056]: Fixes a reference to deallocated stack space during startup when constructing sys.path involving a relative symlink when code was supplied via -c. (discovered via Coverity)

• bpo-41061 [https://bugs.python.org/issue?@action=redirect&bpo=41061]: Fix incorrect expressions and asserts in hashtable code and tests.

• bpo-41052 [https://bugs.python.org/issue?@action=redirect&bpo=41052]: Opt out serialization/deserialization for _random.Random

• bpo-40939 [https://bugs.python.org/issue?@action=redirect&bpo=40939]: Rename PyPegen* functions to PyParser*, so that we can remove the old set of PyParser* functions that were using the old parser, but keep everything backwards-compatible.

• bpo-35975 [https://bugs.python.org/issue?@action=redirect&bpo=35975]: Stefan Behnel reported that cf_feature_version is used even when PyCF_ONLY_AST is not set. This is against the intention and against the documented behavior, so it's been fixed.

• bpo-40939 [https://bugs.python.org/issue?@action=redirect&bpo=40939]: Remove the remaining files from the old parser and the symbol module.

• bpo-40077 [https://bugs.python.org/issue?@action=redirect&bpo=40077]: Convert _bz2 to use PyType_FromSpec().

• bpo-41006 [https://bugs.python.org/issue?@action=redirect&bpo=41006]: The encodings.latin_1 module is no longer imported at startup. Now it is only imported when it is the filesystem encoding or the stdio encoding.

• bpo-40636 [https://bugs.python.org/issue?@action=redirect&bpo=40636]: zip() now supports PEP 618 [https://peps.python.org/pep-0618/]'s strict parameter, which raises a ValueError if the arguments are exhausted at different lengths. Patch by Brandt Bucher.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port _gdbm to multiphase initialization.

• bpo-40985 [https://bugs.python.org/issue?@action=redirect&bpo=40985]: Fix a bug that caused the SyntaxError text to be empty when a file ends with a line ending in a line continuation character (i.e. backslash). The error text should contain the text of the last line.

• bpo-40958 [https://bugs.python.org/issue?@action=redirect&bpo=40958]: Fix a possible buffer overflow in the PEG parser when gathering information for emitting syntax errors. Patch by Pablo Galindo.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port _dbm to multiphase initialization.

• bpo-40957 [https://bugs.python.org/issue?@action=redirect&bpo=40957]: Fix refleak in Pyfopen_obj() when PySys_Audit() fails

• bpo-40950 [https://bugs.python.org/issue?@action=redirect&bpo=40950]: Add a state to the nis module ( PEP 3121 [https://peps.python.org/pep-3121/]) and apply the multiphase initialization. Patch by Donghee Na.

• bpo-40947 [https://bugs.python.org/issue?@action=redirect&bpo=40947]: The Python Path Configuration now takes PyConfig.platlibdir in account.

• bpo-40939 [https://bugs.python.org/issue?@action=redirect&bpo=40939]: Remove the old parser, the parser module and all associated support code, commandline options and environment variables. Patch by Pablo Galindo.

• bpo-40847 [https://bugs.python.org/issue?@action=redirect&bpo=40847]: Fix a bug where a line with only a line continuation character is not considered a blank line at tokenizer level. In such cases, more than a single NEWLINE token was emitted. The old parser was working around the issue, but the new parser threw a SyntaxError for valid input due to this. For example, an empty line following a line continuation character was interpreted as a SyntaxError.

• bpo-40890 [https://bugs.python.org/issue?@action=redirect&bpo=40890]: Each dictionary view now has a mapping attribute that provides a types.MappingProxyType wrapping the original dictionary. Patch contributed by Dennis Sweeney.

• bpo-40889 [https://bugs.python.org/issue?@action=redirect&bpo=40889]: Improved the performance of symmetric difference operations on dictionary item views. Patch by Dennis Sweeney.

• bpo-40904 [https://bugs.python.org/issue?@action=redirect&bpo=40904]: Fix possible segfault in the new PEG parser when parsing fstring containing yield statements with no value (f"{yield}"). Patch by Pablo Galindo

• bpo-40903 [https://bugs.python.org/issue?@action=redirect&bpo=40903]: Fixed a possible segfault in the new PEG parser when producing error messages for invalid assignments of the form p=p=. Patch by Pablo Galindo

• bpo-40880 [https://bugs.python.org/issue?@action=redirect&bpo=40880]: Fix invalid memory read in the new parser when checking newlines in string literals. Patch by Pablo Galindo.

• bpo-40883 [https://bugs.python.org/issue?@action=redirect&bpo=40883]: Fix memory leak in when parsing fstrings in the new parser. Patch by Pablo Galindo

• bpo-40870 [https://bugs.python.org/issue?@action=redirect&bpo=40870]: Raise ValueError when validating custom AST's where the constants True, False and None are used within a ast.Name node.

• bpo-40854 [https://bugs.python.org/issue?@action=redirect&bpo=40854]: Allow overriding sys.platlibdir via a new PYTHONPLATLIBDIR environment variable.

• bpo-40826 [https://bugs.python.org/issue?@action=redirect&bpo=40826]: Fix GIL usage in PyOS_Readline(): lock the GIL to set an exception and pass the Python thread state when checking if there is a pending signal.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port fcntl to multiphase initialization.

• bpo-19468 [https://bugs.python.org/issue?@action=redirect&bpo=19468]: Delete unnecessary instance check in importlib.reload(). Patch by Furkan Önder.

• bpo-40824 [https://bugs.python.org/issue?@action=redirect&bpo=40824]: Unexpected errors in calling the __iter__ method are no longer masked by TypeError in the in operator and functions contains(), indexOf() and countOf() of the operator module.

• bpo-40792 [https://bugs.python.org/issue?@action=redirect&bpo=40792]: Attributes start, stop and step of the range object now always has exact type int. Previously, they could have been an instance of a subclass of int.

• bpo-40780 [https://bugs.python.org/issue?@action=redirect&bpo=40780]: Fix a corner case where g-style string formatting of a float failed to remove trailing zeros.

• bpo-38964 [https://bugs.python.org/issue?@action=redirect&bpo=38964]: When there's a SyntaxError in the expression part of an fstring, the filename attribute of the SyntaxError gets correctly set to the name of the file the fstring resides in.

• bpo-40750 [https://bugs.python.org/issue?@action=redirect&bpo=40750]: Support the "-d" debug flag in the new PEG parser. Patch by Pablo Galindo

• bpo-40217 [https://bugs.python.org/issue?@action=redirect&bpo=40217]: Instances of types created with PyType_FromSpecWithBases() will no longer automatically visit their class object when traversing references in the garbage collector. The user is expected to manually visit the object's class. Patch by Pablo Galindo.

• bpo-39573 [https://bugs.python.org/issue?@action=redirect&bpo=39573]: Py_TYPE() is changed to the inline static function. Patch by Donghee Na.

• bpo-40696 [https://bugs.python.org/issue?@action=redirect&bpo=40696]: Fix a hang that can arise after generator.throw() due to a cycle in the exception context chain.

• bpo-40521 [https://bugs.python.org/issue?@action=redirect&bpo=40521]: Each interpreter now its has own free lists, singletons and caches:

  • Free lists: float, tuple, list, dict, frame, context, asynchronous generator, MemoryError.

  • Singletons: empty tuple, empty bytes string, empty Unicode string, single byte character, single Unicode (latin1) character.

  • Slice cache.

They are no longer shared by all interpreters.

• bpo-40679 [https://bugs.python.org/issue?@action=redirect&bpo=40679]: Certain TypeError messages about missing or extra arguments now include the function's qualified name. Patch by Dennis Sweeney.

• bpo-29590 [https://bugs.python.org/issue?@action=redirect&bpo=29590]: Make the stack trace correct after calling generator.throw() on a generator that has yielded from a yield from.

• bpo-4022 [https://bugs.python.org/issue?@action=redirect&bpo=4022]: Improve performance of generators by not raising internal StopIteration.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port mmap to multiphase initialization.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port _lzma to multiphase initialization.

• bpo-37999 [https://bugs.python.org/issue?@action=redirect&bpo=37999]: Builtin and extension functions that take integer arguments no longer accept Decimals, Fractions and other objects that can be converted to integers only with a loss (e.g. that have the __int__() method but do not have the __index__() method).

• bpo-29882 [https://bugs.python.org/issue?@action=redirect&bpo=29882]: Add int.bit_count(), counting the number of ones in the binary representation of an integer. Patch by Niklas Fiekas.

• bpo-36982 [https://bugs.python.org/issue?@action=redirect&bpo=36982]: Use ncurses extended color functions when available to support terminals with 256 colors, and add the new function curses.has_extended_color_support() to indicate whether extended color support is provided by the underlying ncurses library.

• bpo-19569 [https://bugs.python.org/issue?@action=redirect&bpo=19569]: Add the private macros PyCOMP_DIAG_PUSH, PyCOMP_DIAG_IGNORE_DEPR_DECLS, and PyCOMP_DIAG_POP.

• bpo-26680 [https://bugs.python.org/issue?@action=redirect&bpo=26680]: The int type now supports the x.is_integer() method for compatibility with float.

库

• bpo-41900 [https://bugs.python.org/issue?@action=redirect&bpo=41900]: C14N 2.0 serialisation in xml.etree.ElementTree failed for unprefixed attributes when a default namespace was defined.

• bpo-41887 [https://bugs.python.org/issue?@action=redirect&bpo=41887]: Strip leading spaces and tabs on ast.literal_eval(). Also document stripping of spaces and tabs for eval().

• bpo-41773 [https://bugs.python.org/issue?@action=redirect&bpo=41773]: Note in documentation that random.choices() doesn't support non-finite weights, raise ValueError when given non-finite weights.

• bpo-41840 [https://bugs.python.org/issue?@action=redirect&bpo=41840]: Fix a bug in the symtable module that was causing module-scope global variables to not be reported as both local and global. Patch by Pablo Galindo.

• bpo-41842 [https://bugs.python.org/issue?@action=redirect&bpo=41842]: Add codecs.unregister() function to unregister a codec search function.

• bpo-40564 [https://bugs.python.org/issue?@action=redirect&bpo=40564]: In zipfile.Path, mutate the passed ZipFile object type instead of making a copy. Prevents issues when both the local copy and the caller’s copy attempt to close the same file handle.

• bpo-40670 [https://bugs.python.org/issue?@action=redirect&bpo=40670]: More reliable validation of statements in timeit.Timer. It now accepts "empty" statements (only whitespaces and comments) and rejects misindentent statements.

• bpo-41833 [https://bugs.python.org/issue?@action=redirect&bpo=41833]: The threading.Thread constructor now uses the target name if the target argument is specified but the name argument is omitted.

• bpo-41817 [https://bugs.python.org/issue?@action=redirect&bpo=41817]: fix tkinter.EventType Enum so all members are strings, and none are tuples

• bpo-41810 [https://bugs.python.org/issue?@action=redirect&bpo=41810]: types.EllipsisType, types.NotImplementedType and types.NoneType have been reintroduced, providing a new set of types readily interpretable by static type checkers.

• bpo-41815 [https://bugs.python.org/issue?@action=redirect&bpo=41815]: Fix SQLite3 segfault when backing up closed database. Patch contributed by Peter David McCormick.

• bpo-41816 [https://bugs.python.org/issue?@action=redirect&bpo=41816]: StrEnum added: it ensures that all members are already strings or string candidates

• bpo-41517 [https://bugs.python.org/issue?@action=redirect&bpo=41517]: fix bug allowing Enums to be extended via multiple inheritance

• bpo-39587 [https://bugs.python.org/issue?@action=redirect&bpo=39587]: use the correct mix-in data type when constructing Enums

• bpo-41792 [https://bugs.python.org/issue?@action=redirect&bpo=41792]: Add is_typeddict function to typing.py to check if a type is a TypedDict class

Previously there was no way to check that without using private API. See the relevant issue in python/typing [https://github.com/python/typing/issues/751].

• bpo-41789 [https://bugs.python.org/issue?@action=redirect&bpo=41789]: Honor object overrides in Enum class creation (specifically, __str__, _repr_, __format__, and __reduce_ex__).

• bpo-32218 [https://bugs.python.org/issue?@action=redirect&bpo=32218]: enum.Flag and enum.IntFlag members are now iterable.

• bpo-39651 [https://bugs.python.org/issue?@action=redirect&bpo=39651]: Fix a race condition in the call_soon_threadsafe() method of asyncio.ProactorEventLoop: do nothing if the self-pipe socket has been closed.

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the mashal extension module to the multiphase initialization API ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-1635741 [https://bugs.python.org/issue?@action=redirect&bpo=1635741]: Port the _string extension module to the multiphase initialization API ( PEP 489 [https://peps.python.org/pep-0489/]).

• bpo-41732 [https://bugs.python.org/issue?@action=redirect&bpo=41732]: Added an iterator to memoryview.

• bpo-41720 [https://bugs.python.org/issue?@action=redirect&bpo=41720]: Fixed turtle.Vec2D.__rmul__() for arguments which are not int or float.

• bpo-41696 [https://bugs.python.org/issue?@action=redirect&bpo=41696]: Fix handling of debug mode in asyncio.run(). This allows setting PYTHONASYNCIODEBUG or -X dev to enable asyncio debug mode when using asyncio.run().

• bpo-41687 [https://bugs.python.org/issue?@action=redirect&bpo=41687]: Fix implementation of sendfile to be compatible with Solaris.

• bpo-41662 [https://bugs.python.org/issue?@action=redirect&bpo=41662]: No longer override exceptions raised in __len__() of a sequence of parameters in sqlite3 with ProgrammingError.

• bpo-39010 [https://bugs.python.org/issue?@action=redirect&bpo=39010]: Restarting a ProactorEventLoop on Windows no longer logs spurious ConnectionResetErrors.

• bpo-41638 [https://bugs.python.org/issue?@action=redirect&bpo=41638]: ProgrammingError message for absent parameter in sqlite3 contains now the name of the parameter instead of its index when parameters are supplied as a dict.

• bpo-41662 [https://bugs.python.org/issue?@action=redirect&bpo=41662]: Fixed crash when mutate list of parameters during iteration in sqlite3.

• bpo-41513 [https://bugs.python.org/issue?@action=redirect&bpo=41513]: Improved the accuracy of math.hypot(). Internally, each step is computed with extra precision so that the result is now almost always correctly rounded.

• bpo-41609 [https://bugs.python.org/issue?@action=redirect&bpo=41609]: The pdb whatis command correctly reports instance methods as 'Method' rather than 'Function'.

• bpo-39994 [https://bugs.python.org/issue?@action=redirect&bpo=39994]: Fixed pprint's handling of dict subclasses that override repr.

• bpo-32751 [https://bugs.python.org/issue?@action=redirect&bpo=32751]: When cancelling the task due to a timeout, asyncio.wait_for() will now wait until the cancellation is complete also in the case when timeout is <= 0, like it does with positive timeouts.

• bpo-37658 [https://bugs.python.org/issue?@action=redirect&bpo=37658]: asyncio.wait_for() now properly handles races between cancellation of itself and the completion of the wrapped awaitable.

• bpo-40782 [https://bugs.python.org/issue?@action=redirect&bpo=40782]: Change the method asyncio.AbstractEventLoop.run_in_executor to not be a coroutine.

• bpo-41520 [https://bugs.python.org/issue?@action=redirect&bpo=41520]: Fix codeop regression that prevented turning compile warnings into errors.

• bpo-41528 [https://bugs.python.org/issue?@action=redirect&bpo=41528]: turtle uses math module functions to convert degrees to radians and vice versa and to calculate vector norm

• bpo-41513 [https://bugs.python.org/issue?@action=redirect&bpo=41513]: Minor algorithmic improvement to math.hypot() and math.dist() giving small gains in speed and accuracy.

• bpo-41503 [https://bugs.python.org/issue?@action=redirect&bpo=41503]: Fixed a race between setTarget and flush in logging.handlers.MemoryHandler.

• bpo-41497 [https://bugs.python.org/issue?@action=redirect&bpo=41497]: Fix potential UnicodeDecodeError in dis module.

• bpo-41467 [https://bugs.python.org/issue?@action=redirect&bpo=41467]: On Windows, fix asyncio recv_into() return value when the socket/pipe is closed (BrokenPipeError): return 0 rather than an empty byte string (b'').

• bpo-41425 [https://bugs.python.org/issue?@action=redirect&bpo=41425]: Make tkinter doc example runnable.

• bpo-41421 [https://bugs.python.org/issue?@action=redirect&bpo=41421]: Make an algebraic simplification to random.paretovariate(). It now is slightly less subject to round-off error and is slightly faster. Inputs that used to cause ZeroDivisionError now cause an OverflowError instead.

• bpo-41440 [https://bugs.python.org/issue?@action=redirect&bpo=41440]: Add os.cpu_count() support for VxWorks RTOS.

• bpo-41316 [https://bugs.python.org/issue?@action=redirect&bpo=41316]: Fix the tarfile module to write only basename of TAR file to GZIP compression header.

• bpo-41384 [https://bugs.python.org/issue?@action=redirect&bpo=41384]: Raise TclError instead of TypeError when an unknown option is passed to tkinter.OptionMenu.

• bpo-41317 [https://bugs.python.org/issue?@action=redirect&bpo=41317]: Use add_done_callback() in asyncio.loop.sock_accept() to unsubscribe reader early on cancellation.

• bpo-41364 [https://bugs.python.org/issue?@action=redirect&bpo=41364]: Reduce import overhead of uuid.

• bpo-35328 [https://bugs.python.org/issue?@action=redirect&bpo=35328]: Set the environment variable VIRTUAL_ENV_PROMPT at venv activation.

• bpo-41341 [https://bugs.python.org/issue?@action=redirect&bpo=41341]: Recursive evaluation of typing.ForwardRef in get_type_hints.

• bpo-41344 [https://bugs.python.org/issue?@action=redirect&bpo=41344]: Prevent creating shared_memory.SharedMemory objects with size=0.

• bpo-41333 [https://bugs.python.org/issue?@action=redirect&bpo=41333]: collections.OrderedDict.pop() is now 2 times faster.

• bpo-41288 [https://bugs.python.org/issue?@action=redirect&bpo=41288]: Unpickling invalid NEWOBJ_EX opcode with the C implementation raises now UnpicklingError instead of crashing.

• bpo-39017 [https://bugs.python.org/issue?@action=redirect&bpo=39017]: Avoid infinite loop when reading specially crafted TAR files using the tarfile module ( CVE 2019-20907 [https://www.cve.org/CVERecord?id=CVE-2019-20907]).

• bpo-41273 [https://bugs.python.org/issue?@action=redirect&bpo=41273]: Speed up any transport using _ProactorReadPipeTransport by calling recv_into instead of recv, thus not creating a new buffer for each recv call in the transport's read loop.

• bpo-41235 [https://bugs.python.org/issue?@action=redirect&bpo=41235]: Fix the error handling in ssl.SSLContext.load_dh_params().

• bpo-41207 [https://bugs.python.org/issue?@action=redirect&bpo=41207]: In distutils.spawn, restore expectation that DistutilsExecError is raised when the command is not found.

• bpo-29727 [https://bugs.python.org/issue?@action=redirect&bpo=29727]: Register array.array as a MutableSequence. Patch by Pablo Galindo.

• bpo-39168 [https://bugs.python.org/issue?@action=redirect&bpo=39168]: Remove the _new_ method of typing.Generic.

• bpo-41194 [https://bugs.python.org/issue?@action=redirect&bpo=41194]: Fix a crash in the _ast module: it can no longer be loaded more than once. It now uses a global state rather than a module state.

• bpo-41195 [https://bugs.python.org/issue?@action=redirect&bpo=41195]: Add readonly ssl.SSLContext.security_level attribute to retrieve the context's security level.

• bpo-41193 [https://bugs.python.org/issue?@action=redirect&bpo=41193]: The write_history() atexit function of the readline completer now ignores any OSError to ignore error if the filesystem is readonly, instead of only ignoring FileNotFoundError and PermissionError.

• bpo-41182 [https://bugs.python.org/issue?@action=redirect&bpo=41182]: selector: use DefaultSelector based upon implementation

• bpo-41161 [https://bugs.python.org/issue?@action=redirect&bpo=41161]: The decimal module now requires libmpdec-2.5.0. Users of —with-system-libmpdec should update their system library.

• bpo-40874 [https://bugs.python.org/issue?@action=redirect&bpo=40874]: The decimal module now requires libmpdec-2.5.0.

• bpo-41138 [https://bugs.python.org/issue?@action=redirect&bpo=41138]: Fixed the trace module CLI for Python source files with non-UTF-8 encoding.

• bpo-31082 [https://bugs.python.org/issue?@action=redirect&bpo=31082]: Use the term "iterable" in the docstring for functools.reduce().

• bpo-40521 [https://bugs.python.org/issue?@action=redirect&bpo=40521]: Remove freelist from collections.deque().

• bpo-31938 [https://bugs.python.org/issue?@action=redirect&bpo=31938]: Fix default-value signatures of several functions in the select module - by Anthony Sottile.

• bpo-41068 [https://bugs.python.org/issue?@action=redirect&bpo=41068]: Fixed reading files with nonASCII names from ZIP archive directly after writing them.

• bpo-41058 [https://bugs.python.org/issue?@action=redirect&bpo=41058]: pdb.find_function() now correctly determines the source file encoding.

• bpo-41056 [https://bugs.python.org/issue?@action=redirect&bpo=41056]: Invalid file descriptor values are now prevented from being passed to os.fpathconf. (discovered by Coverity)

• bpo-41056 [https://bugs.python.org/issue?@action=redirect&bpo=41056]: Fix a NULL pointer dereference within the ssl module during a MemoryError in the keylog callback. (discovered by Coverity)

• bpo-41056 [https://bugs.python.org/issue?@action=redirect&bpo=41056]: Fixed an instance where a MemoryError within the zoneinfo module might not be reported or not reported at its source. (found by Coverity)

• bpo-41048 [https://bugs.python.org/issue?@action=redirect&bpo=41048]: mimetypes.read_mime_types() function reads the rule file using UTF-8 encoding, not the locale encoding. Patch by Srinivas Reddy Thatiparthy.

• bpo-41043 [https://bugs.python.org/issue?@action=redirect&bpo=41043]: Fixed the use of glob() in the stdlib: literal part of the path is now always correctly escaped.

• bpo-41025 [https://bugs.python.org/issue?@action=redirect&bpo=41025]: Fixed an issue preventing the C implementation of zoneinfo.ZoneInfo from being subclassed.

• bpo-35018 [https://bugs.python.org/issue?@action=redirect&bpo=35018]: Add the xml.sax.handler.LexicalHandler class that is present in other SAX XML implementations.

• bpo-41002 [https://bugs.python.org/issue?@action=redirect&bpo=41002]: Improve performance of HTTPResponse.read with a given amount. Patch by Bruce Merry.

• bpo-40448 [https://bugs.python.org/issue?@action=redirect&bpo=40448]: ensurepip now disables the use of pip cache when installing the bundled versions of pip and setuptools. Patch by Krzysztof Konopko.

• bpo-40967 [https://bugs.python.org/issue?@action=redirect&bpo=40967]: Removed asyncio.Task.current_task() and asyncio.Task.all_tasks(). Patch contributed by Rémi Lapeyre.

• bpo-40924 [https://bugs.python.org/issue?@action=redirect&bpo=40924]: Ensure importlib.resources.path returns an extant path for the SourceFileLoader's resource reader. Avoids the regression identified in master while a long-term solution is devised.

• bpo-40955 [https://bugs.python.org/issue?@action=redirect&bpo=40955]: Fix a minor memory leak in subprocess module when extra_groups was specified.

• bpo-40855 [https://bugs.python.org/issue?@action=redirect&bpo=40855]: The standard deviation and variance functions in the statistics module were ignoring their mu and xbar arguments.

• bpo-40939 [https://bugs.python.org/issue?@action=redirect&bpo=40939]: Use the new PEG parser when generating the stdlib keyword module.

• bpo-23427 [https://bugs.python.org/issue?@action=redirect&bpo=23427]: Add sys.orig_argv attribute: the list of the original command line arguments passed to the Python executable.

• bpo-33689 [https://bugs.python.org/issue?@action=redirect&bpo=33689]: Ignore empty or whitespace-only lines in .pth files. This matches the documentated behavior. Before, empty lines caused the site-packages dir to appear multiple times in sys.path. By Ido Michael, contributors Malcolm Smith and Tal Einat.

• bpo-40884 [https://bugs.python.org/issue?@action=redirect&bpo=40884]: Added a defaults parameter to logging.Formatter, to allow specifying default values for custom fields. Patch by Asaf Alon and Bar Harel.

• bpo-40876 [https://bugs.python.org/issue?@action=redirect&bpo=40876]: Clarify error message in the csv module.

• bpo-39791 [https://bugs.python.org/issue?@action=redirect&bpo=39791]: Refresh importlib.metadata from importlib_metadata 1.6.1.

• bpo-40807 [https://bugs.python.org/issue?@action=redirect&bpo=40807]: Stop codeop._maybe_compile, used by code.InteractiveInterpreter (and IDLE). from emitting each warning three times.

• bpo-32604 [https://bugs.python.org/issue?@action=redirect&bpo=32604]: Fix reference leak in the select module when the module is imported in a subinterpreter.

• bpo-39791 [https://bugs.python.org/issue?@action=redirect&bpo=39791]: Builtin loaders (SourceFileLoader and ZipImporter) now supply TraversableResources implementations for ResourceReader, and the fallback function has been removed.

• bpo-39314 [https://bugs.python.org/issue?@action=redirect&bpo=39314]: rlcompleter.Completer and the standard Python shell now close the parenthesis for functions that take no arguments. Patch contributed by Rémi Lapeyre.

• bpo-17005 [https://bugs.python.org/issue?@action=redirect&bpo=17005]: The topological sort functionality that was introduced initially in the functools module has been moved to a new graphlib module to better accommodate the new tools and keep the original scope of the functools module. Patch by Pablo Galindo

• bpo-40834 [https://bugs.python.org/issue?@action=redirect&bpo=40834]: Fix truncate when sending str object with_xxsubinterpreters.channel_send.

• bpo-40755 [https://bugs.python.org/issue?@action=redirect&bpo=40755]: Add rich comparisons to collections.Counter().

• bpo-26407 [https://bugs.python.org/issue?@action=redirect&bpo=26407]: Unexpected errors in calling the __iter__ method are no longer masked by TypeError in csv.reader(), csv.writer.writerow() and csv.writer.writerows().

• bpo-39384 [https://bugs.python.org/issue?@action=redirect&bpo=39384]: Fixed email.contentmanager to allow set_content() to set a null string.

• bpo-40744 [https://bugs.python.org/issue?@action=redirect&bpo=40744]: The sqlite3 module uses SQLite API functions that require SQLite v3.7.3 or higher. This patch removes support for older SQLite versions, and explicitly requires SQLite 3.7.3 both at build, compile and runtime. Patch by Sergey Fedoseev and Erlend E. Aasland.

• bpo-40777 [https://bugs.python.org/issue?@action=redirect&bpo=40777]: Initialize PyDateTime_IsoCalendarDateType.tp_base at runtime to avoid errors on some compilers.

• bpo-38488 [https://bugs.python.org/issue?@action=redirect&bpo=38488]: Update ensurepip to install pip 20.1.1 and setuptools 47.1.0.

• bpo-40792 [https://bugs.python.org/issue?@action=redirect&bpo=40792]: The result of operator.index() now always has exact type int. Previously, the result could have been an instance of a subclass of int.

• bpo-40767 [https://bugs.python.org/issue?@action=redirect&bpo=40767]: webbrowser now properly finds the default browser in pure Wayland systems by checking the WAYLAND_DISPLAY environment variable. Patch contributed by Jérémy Attali.

• bpo-40791 [https://bugs.python.org/issue?@action=redirect&bpo=40791]: hashlib.compare_digest() uses OpenSSL's CRYPTO_memcmp() function when OpenSSL is available.

• bpo-40795 [https://bugs.python.org/issue?@action=redirect&bpo=40795]: ctypes module: If ctypes fails to convert the result of a callback or if a ctypes callback function raises an exception, sys.unraisablehook is now called with an exception set. Previously, the error was logged into stderr by PyErr_Print().

• bpo-16995 [https://bugs.python.org/issue?@action=redirect&bpo=16995]: Add base64.b32hexencode() and base64.b32hexdecode() to support the Base32 Encoding with Extended Hex Alphabet.

• bpo-30008 [https://bugs.python.org/issue?@action=redirect&bpo=30008]: Fix ssl code to be compatible with OpenSSL 1.1.x builds that use no-deprecated and --api=1.1.0.

• bpo-30064 [https://bugs.python.org/issue?@action=redirect&bpo=30064]: Fix asyncio loop.sock_* race condition issue

• bpo-40759 [https://bugs.python.org/issue?@action=redirect&bpo=40759]: Deprecate the symbol module.

• bpo-40756 [https://bugs.python.org/issue?@action=redirect&bpo=40756]: The second argument (extra) of LoggerAdapter.__init__ now defaults to None.

• bpo-37129 [https://bugs.python.org/issue?@action=redirect&bpo=37129]: Add a new os.RWF_APPEND flag for os.pwritev().

• bpo-40737 [https://bugs.python.org/issue?@action=redirect&bpo=40737]: Fix possible reference leak for sqlite3 initialization.

• bpo-40726 [https://bugs.python.org/issue?@action=redirect&bpo=40726]: Handle cases where the end_lineno is None on ast.increment_lineno().

• bpo-40698 [https://bugs.python.org/issue?@action=redirect&bpo=40698]: distutils upload creates SHA2-256 and Blake2b-256 digests. MD5 digests is skipped if platform blocks MD5.

• bpo-40695 [https://bugs.python.org/issue?@action=redirect&bpo=40695]: hashlib no longer falls back to builtin hash implementations when OpenSSL provides a hash digest and the algorithm is blocked by security policy.

• bpo-9216 [https://bugs.python.org/issue?@action=redirect&bpo=9216]: hashlib.new() passed usedforsecurity to OpenSSL EVP constructor _hashlib.new(). test_hashlib and test_smtplib handle strict security policy better.

• bpo-40614 [https://bugs.python.org/issue?@action=redirect&bpo=40614]: ast.parse() will not parse self documenting expressions in fstrings when passed feature_version is less than (3, 8).

• bpo-40626 [https://bugs.python.org/issue?@action=redirect&bpo=40626]: Add h5 file extension as MIME Type application/x-hdf5, as per HDF Group recommendation for HDF5 formatted data files. Patch contributed by Mark Schwab.

• bpo-25920 [https://bugs.python.org/issue?@action=redirect&bpo=25920]: On macOS, when building Python for macOS 10.4 and older, which wasn't the case for python.org macOS installer, socket.getaddrinfo() no longer uses an internal lock to prevent race conditions when calling getaddrinfo() which is threadsafe since macOS 10.5. Python 3.9 requires macOS 10.6 or newer. The internal lock caused random hang on fork when another thread was calling socket.getaddrinfo(). The lock was also used on FreeBSD older than 5.3, OpenBSD older than 201311 and NetBSD older than 4.

• bpo-40671 [https://bugs.python.org/issue?@action=redirect&bpo=40671]: Prepare _hashlib for PEP 489 [https://peps.python.org/pep-0489/] and use PyModule_AddType().

• bpo-32309 [https://bugs.python.org/issue?@action=redirect&bpo=32309]: Added a new coroutine asyncio.to_thread(). It is mainly used for running IO-bound functions in a separate thread to avoid blocking the event loop, and essentially works as a high-level version of run_in_executor() that can directly take keyword arguments.

• bpo-36543 [https://bugs.python.org/issue?@action=redirect&bpo=36543]: Restored the deprecated xml.etree.cElementTree module.

• bpo-40611 [https://bugs.python.org/issue?@action=redirect&bpo=40611]: MAP_POPULATE constant has now been added to the list of exported mmap module flags.

• bpo-39881 [https://bugs.python.org/issue?@action=redirect&bpo=39881]: PEP 554 for use in the test suite. (Patch By Joannah Nanjekye)

• bpo-13097 [https://bugs.python.org/issue?@action=redirect&bpo=13097]: ctypes now raises an ArgumentError when a callback is invoked with more than 1024 arguments.

• bpo-39385 [https://bugs.python.org/issue?@action=redirect&bpo=39385]: A new test assertion contextmanager, unittest.assertNoLogs() will ensure a given block of code emits no log messages using the logging module. Contributed by Kit Yan Choi.

• bpo-23082 [https://bugs.python.org/issue?@action=redirect&bpo=23082]: Updated the error message and docs of PurePath.relative_to() to better reflect the function behaviour.

• bpo-40318 [https://bugs.python.org/issue?@action=redirect&bpo=40318]: Use SQLite3 trace v2 API, if it is available.

• bpo-40105 [https://bugs.python.org/issue?@action=redirect&bpo=40105]: ZipFile truncates files to avoid corruption when a shorter comment is provided in append ("a") mode. Patch by Jan Mazur.

• bpo-40084 [https://bugs.python.org/issue?@action=redirect&bpo=40084]: Fix Enum.__dir__: dir(Enum.member) now includes attributes as well as methods.

• bpo-31122 [https://bugs.python.org/issue?@action=redirect&bpo=31122]: ssl.wrap_socket() now raises ssl.SSLEOFError rather than OSError when peer closes connection during TLS negotiation

• bpo-39728 [https://bugs.python.org/issue?@action=redirect&bpo=39728]: fix default missing so a duplicate ValueError is not set as the __context__ of the original ValueError.

• bpo-39244 [https://bugs.python.org/issue?@action=redirect&bpo=39244]: Fixed multiprocessing.context.get_allstartmethods to properly return the default method first on macOS.

• bpo-39040 [https://bugs.python.org/issue?@action=redirect&bpo=39040]: Fix parsing of invalid mime headers parameters by collapsing whitespace between encoded words in a bare-quote-string.

• bpo-38731 [https://bugs.python.org/issue?@action=redirect&bpo=38731]: Add --quiet option to commandline interface of py_compile. Patch by Gregory Schevchenko.

• bpo-35714 [https://bugs.python.org/issue?@action=redirect&bpo=35714]: struct.error is now raised if there is a null character in a struct format string.

• bpo-38144 [https://bugs.python.org/issue?@action=redirect&bpo=38144]: Added the root_dir and dir_fd parameters in glob.glob().

• bpo-26543 [https://bugs.python.org/issue?@action=redirect&bpo=26543]: Fix IMAP4.noop() when debug mode is enabled (ex: imaplib.Debug = 3).

• bpo-12178 [https://bugs.python.org/issue?@action=redirect&bpo=12178]: csv.writer() now correctly escapes escapechar when input contains escapechar. Patch by Catalin Iacob, Berker Peksag, and Itay Elbirt.

• bpo-36290 [https://bugs.python.org/issue?@action=redirect&bpo=36290]: AST nodes are now raising TypeError on conflicting keyword arguments. Patch contributed by Rémi Lapeyre.

• bpo-33944 [https://bugs.python.org/issue?@action=redirect&bpo=33944]: Added site.py site-packages tracing in verbose mode.

• bpo-35078 [https://bugs.python.org/issue?@action=redirect&bpo=35078]: Refactor formatweekday, formatmonthname methods in LocaleHTMLCalendar and LocaleTextCalendar classes in calendar module to call the base class methods.This enables customizable CSS classes for LocaleHTMLCalendar. Patch by Srinivas Reddy Thatiparthy

• bpo-29620 [https://bugs.python.org/issue?@action=redirect&bpo=29620]: assertWarns() no longer raises a RuntimeException when accessing a module's __warningregistry__ causes importation of a new module, or when a new module is imported in another thread. Patch by Kernc.

• bpo-31844 [https://bugs.python.org/issue?@action=redirect&bpo=31844]: Remove ParserBase.error() method from the private and undocumented _markupbase module. html.parser.HTMLParser is the only subclass of ParserBase and its error() implementation was deprecated in Python 3.4 and removed in Python 3.5.

• bpo-34226 [https://bugs.python.org/issue?@action=redirect&bpo=34226]: Fix cgi.parse_multipart without content_length. Patch by Roger Duran

• bpo-33660 [https://bugs.python.org/issue?@action=redirect&bpo=33660]: Fix pathlib.PosixPath to resolve a relative path located on the root directory properly.

• bpo-28557 [https://bugs.python.org/issue?@action=redirect&bpo=28557]: Improve the error message for a misbehaving rawio.readinto

• bpo-26680 [https://bugs.python.org/issue?@action=redirect&bpo=26680]: The d.is_integer() method is added to the Decimal type, for compatibility with other number types.

• bpo-26680 [https://bugs.python.org/issue?@action=redirect&bpo=26680]: The x.is_integer() method is incorporated into the abstract types of the numeric tower, Real, Rational and Integral, with appropriate default implementations.