Changelog¶
Python 3.8.20 final¶
Release date: 2024-09-06
Windows¶
Tests¶
gh-112769: The tests now correctly compare zlib version when
zlib.ZLIB_RUNTIME_VERSION
contains non-integer suffixes. For example zlib-ng defines the version as1.3.0.zlib-ng
.gh-117187: Fix XML tests for vanilla Expat <2.6.0.
Security¶
gh-123678: Upgrade libexpat to 2.6.3
gh-121957: Fixed missing audit events around interactive use of Python, now also properly firing for
python -i
, as well as forpython -m asyncio
. The event in question iscpython.run_stdin
.gh-122133: Authenticate the socket connection for the
socket.socketpair()
fallback on platforms whereAF_UNIX
is not available like Windows.Patch by Gregory P. Smith <greg@krypto.org> and Seth Larson <seth@python.org>. Reported by Ellie <el@horse64.org>
gh-121285: Remove backtracking from tarfile header parsing for
hdrcharset
, PAX, and GNU sparse headers.gh-118486:
os.mkdir()
on Windows now accepts mode of0o700
to restrict the new directory to the current user. This fixes CVE-2024-4030 affectingtempfile.mkdtemp()
in scenarios where the base temporary directory is more permissive than the default.gh-114572:
ssl.SSLContext.cert_store_stats()
andssl.SSLContext.get_ca_certs()
now correctly lock access to the certificate store, when thessl.SSLContext
is shared across multiple threads.gh-116741: Update bundled libexpat to 2.6.2
Library¶
gh-123270: Applied a more surgical fix for malformed payloads in
zipfile.Path
causing infinite loops (gh-122905) without breaking contents using legitimate characters.gh-123067: Fix quadratic complexity in parsing
"
-quoted cookie values with backslashes byhttp.cookies
.gh-121650:
email
headers with embedded newlines are now quoted on output. Thegenerator
will now refuse to serialize (write) headers that are unsafely folded or delimited; seeverify_generated_headers
. (Contributed by Bas Bloemsaat and Petr Viktorin in gh-121650.)gh-113171: Fixed various false positives and false negatives in
ipaddress.IPv4Address.is_private
(see these docs for details)
Also in the corresponding
ipaddress.IPv4Network
andipaddress.IPv6Network
attributes.gh-102988:
email.utils.getaddresses()
andemail.utils.parseaddr()
now return('', '')
2-tuples in more situations where invalid email addresses are encountered instead of potentially inaccurate values. Add optional strict parameter to these two functions: usestrict=False
to get the old behavior, accept malformed inputs.getattr(email.utils, 'supports_strict_parsing', False)
can be use to check if the strict paramater is available. Patch by Thomas Dwyer and Victor Stinner to improve the CVE-2023-27043 fix.gh-67693: Fix
urllib.parse.urlunparse()
andurllib.parse.urlunsplit()
for URIs with path starting with multiple slashes and no authority. Based on patch by Ashwin Ramaswami.
Core and Builtins¶
gh-112275: A deadlock involving
pystate.c
’sHEAD_LOCK
inposixmodule.c
at fork is now fixed. Patch by ChuBoning based on previous Python 3.12 fix by Victor Stinner.
Python 3.8.19 final¶
Release date: 2024-03-19
Security¶
Core and Builtins¶
gh-102388: Fix a bug where
iso2022_jp_3
andiso2022_jp_2004
codecs read out of bounds
Library¶
gh-115197:
urllib.request
no longer resolves the hostname before checking it against the system’s proxy bypass list on macOS and Windows.gh-115133: Fix tests for
XMLPullParser
with Expat 2.6.0.gh-81194: Fix a crash in
socket.if_indextoname()
with specific value (UINT_MAX). Fix an integer overflow insocket.if_indextoname()
on 64-bit non-Windows platforms.gh-109858: Protect
zipfile
from “quoted-overlap” zipbomb. It now raises BadZipFile when try to read an entry that overlaps with other entry or central directory.gh-107077: Seems that in some conditions, OpenSSL will return
SSL_ERROR_SYSCALL
instead ofSSL_ERROR_SSL
when a certification verification has failed, but the error parameters will still containERR_LIB_SSL
andSSL_R_CERTIFICATE_VERIFY_FAILED
. We are now detecting this situation and raising the appropiatessl.SSLCertVerificationError
. Patch by Pablo Galindogh-91133: Fix a bug in
tempfile.TemporaryDirectory
cleanup, which now no longer dereferences symlinks when working around file system permission errors.
Documentation¶
gh-115399: Document CVE-2023-52425 of Expat <2.6.0 under “XML vulnerabilities”.
Tests¶
gh-108310: SSL tests for pre-handshake close were previously not enabled on Python 3.8 due to an incorrect backport. This is now fixed. Patch by Lumír Balhar.
Windows¶
Python 3.8.18 final¶
Release date: 2023-08-24
Security¶
gh-108310: Fixed an issue where instances of
ssl.SSLSocket
were vulnerable to a bypass of the TLS handshake and included protections (like certificate verification) and treating sent unencrypted data as if it were post-handshake TLS encrypted data. Security issue reported as CVE-2023-40217 by Aapo Oksman. Patch by Gregory P. Smith.
Library¶
gh-107845:
tarfile.data_filter()
now takes the location of symlinks into account when determining their target, so it will no longer reject some valid tarballs withLinkOutsideDestinationError
.
Tools/Demos¶
gh-107565: Update multissltests and GitHub CI workflows to use OpenSSL 1.1.1v, 3.0.10, and 3.1.2.
Python 3.8.17 final¶
Release date: 2023-06-06
Security¶
gh-103142: The version of OpenSSL used in our binary builds has been upgraded to 1.1.1u to address several CVEs.
gh-99889: Fixed a security in flaw in
uu.decode()
that could allow for directory traversal based on the input if noout_file
was specified.gh-104049: Do not expose the local on-disk location in directory indexes produced by
http.client.SimpleHTTPRequestHandler
.gh-102153:
urllib.parse.urlsplit()
now strips leading C0 control and space characters following the specification for URLs defined by WHATWG in response to CVE-2023-24329. Patch by Illia Volochii.gh-101727: Updated the OpenSSL version used in Windows and macOS binary release builds to 1.1.1t to address CVE-2023-0286, CVE-2022-4303, and CVE-2022-4303 per the OpenSSL 2023-02-07 security advisory.
gh-101283:
subprocess.Popen
now uses a safer approach to findcmd.exe
when launching withshell=True
. Patch by Eryk Sun, based on a patch by Oleg Iarygin.
Library¶
gh-103935: Use
io.open_code()
for files to be executed instead of rawopen()
gh-102953: The extraction methods in
tarfile
, andshutil.unpack_archive()
, have a new a filter argument that allows limiting tar features than may be surprising or dangerous, such as creating files outside the destination directory. See Filtros de extração for details.gh-101997: Upgrade pip wheel bundled with ensurepip (pip 23.0.1)
Build¶
gh-102306: [3.8] Avoid GHA CI macOS test_posix failure by using the appropriate macOS SDK.
Windows¶
gh-100180: Update Windows installer to OpenSSL 1.1.1s
macOS¶
gh-103142: Update macOS installer to use OpenSSL 1.1.1u.
Python 3.8.16 final¶
Release date: 2022-12-06
Security¶
gh-100001:
python -m http.server
no longer allows terminal control characters sent within a garbage request to be printed to the stderr server log.This is done by changing the
http.server
BaseHTTPRequestHandler
.log_message
method to replace control characters with a\xHH
hex escape before printing.gh-87604: Avoid publishing list of active per-interpreter audit hooks via the
gc
modulegh-98433: The IDNA codec decoder used on DNS hostnames by
socket
orasyncio
related name resolution functions no longer involves a quadratic algorithm. This prevents a potential CPU denial of service if an out-of-spec excessive length hostname involving bidirectional characters were decoded. Some protocols such asurllib
http3xx
redirects potentially allow for an attacker to supply such a name.gh-98739: Update bundled libexpat to 2.5.0
gh-98517: Port XKCP’s fix for the buffer overflows in SHA-3 (CVE-2022-37454).
gh-68966: The deprecated mailcap module now refuses to inject unsafe text (filenames, MIME types, parameters) into shell commands. Instead of using such text, it will warn and act as if a match was not found (or for test commands, as if the test failed).
Python 3.8.15 final¶
Release date: 2022-10-11
Security¶
gh-97616: Fix multiplying a list by an integer (
list *= int
): detect the integer overflow when the new allocated length is close to the maximum size. Issue reported by Jordan Limor. Patch by Victor Stinner.gh-97612: Fix a shell code injection vulnerability in the
get-remote-certificate.py
example script. The script no longer uses a shell to runopenssl
commands. Issue reported and initial fix by Caleb Shortt. Patch by Victor Stinner.
Core and Builtins¶
gh-96848: Fix command line parsing: reject
-X int_max_str_digits
option with no value (invalid) when thePYTHONINTMAXSTRDIGITS
environment variable is set to a valid limit. Patch by Victor Stinner.gh-95778: When
ValueError
is raised if an integer is larger than the limit, mention thesys.set_int_max_str_digits()
function in the error message. Patch by Victor Stinner.
Library¶
gh-97005: Update bundled libexpat to 2.4.9
Windows¶
Python 3.8.14 final¶
Release date: 2022-09-06
Security¶
gh-95778: Converting between
int
andstr
in bases other than 2 (binary), 4, 8 (octal), 16 (hexadecimal), or 32 such as base 10 (decimal) now raises aValueError
if the number of digits in string form is above a limit to avoid potential denial of service attacks due to the algorithmic complexity. This is a mitigation for CVE-2020-10735.This new limit can be configured or disabled by environment variable, command line flag, or
sys
APIs. See the integer string conversion length limitation documentation. The default limit is 4300 digits in string form.Patch by Gregory P. Smith [Google] and Christian Heimes [Red Hat] with feedback from Victor Stinner, Thomas Wouters, Steve Dower, Ned Deily, and Mark Dickinson.
gh-87389:
http.server
: Fix an open redirection vulnerability in the HTTP server when an URI path starts with//
. Vulnerability discovered, and initial fix proposed, by Hamza Avvan.
Core and Builtins¶
gh-93065: Fix contextvars HAMT implementation to handle iteration over deep trees.
The bug was discovered and fixed by Eli Libman. See MagicStack/immutables#84 for more details.
Library¶
bpo-46197: Fix
ensurepip
environment isolation for subprocess runningpip
.bpo-36073: Raise
ProgrammingError
instead of segfaulting on recursive usage of cursors insqlite3
converters. Patch by Sergey Fedoseev.
Documentation¶
Tests¶
Windows¶
bpo-47194: Update
zlib
to v1.2.12 to resolve CVE-2018-25032.
Python 3.8.13 final¶
Release date: 2022-03-15
Core and Builtins¶
bpo-46794: Bump up the libexpat version into 2.4.6
Library¶
bpo-46985: Upgrade pip wheel bundled with ensurepip (pip 22.0.4)
bpo-46932: Update bundled libexpat to 2.4.7
bpo-46811: Make test suite support Expat >=2.4.5
bpo-46784: Fix libexpat symbols collisions with user dynamically loaded or statically linked libexpat in embedded Python.
bpo-46756: Fix a bug in
urllib.request.HTTPPasswordMgr.find_user_password()
andurllib.request.HTTPPasswordMgrWithPriorAuth.is_authenticated()
which allowed to bypass authorization. For example, access to URIexample.org/foobar
was allowed if the user was authorized for URIexample.org/foo
.bpo-46400: expat: Update libexpat from 2.4.1 to 2.4.4
bpo-46474: In
importlib.metadata.EntryPoint.pattern
, avoid potential REDoS by limiting ambiguity in consecutive whitespace.bpo-44849: Fix the
os.set_inheritable()
function on FreeBSD 14 for file descriptor opened with theO_PATH
flag: ignore theEBADF
error onioctl()
, fallback on thefcntl()
implementation. Patch by Victor Stinner.
Documentation¶
bpo-41028: Language and version switchers, previously maintained in every cpython branches, are now handled by docsbuild-script.
Tests¶
bpo-45195: Fix test_readline.test_nonascii(): sometimes, the newline character is not written at the end, so don’t expect it in the output. Patch by Victor Stinner.
bpo-44949: Fix auto history tests of test_readline: sometimes, the newline character is not written at the end, so don’t expect it in the output.
Build¶
bpo-47024: Update Windows builds and macOS installer build to use OpenSSL 1.1.1n.
bpo-45405: Prevent
internal configure error
when runningconfigure
with recent versions of clang. Patch by David Bohman.bpo-45220: Avoid building with the Windows 11 SDK previews automatically. This may be overridden by setting the
DefaultWindowsSDKVersion
environment variable before building.
Windows¶
macOS¶
bpo-44828: Avoid tkinter file dialog failure on macOS 12 Monterey when using the Tk 8.6.11 provided by python.org macOS installers. Patch by Marc Culler of the Tk project.
Python 3.8.12 final¶
Release date: 2021-08-30
Security¶
bpo-42278: Replaced usage of
tempfile.mktemp()
withTemporaryDirectory
to avoid a potential race condition.bpo-44394: Update the vendored copy of libexpat to 2.4.1 (from 2.2.8) to get the fix for the CVE-2013-0340 “Billion Laughs” vulnerability. This copy is most used on Windows and macOS.
bpo-43124: Made the internal
putcmd
function insmtplib
sanitize input for presence of\r
and\n
characters to avoid (unlikely) command injection.bpo-36384:
ipaddress
module no longer accepts any leading zeros in IPv4 address strings. Leading zeros are ambiguous and interpreted as octal notation by some libraries. For example the legacy functionsocket.inet_aton()
treats leading zeros as octal notation. glibc implementation of moderninet_pton()
does not accept any leading zeros. For a while theipaddress
module used to accept ambiguous leading zeros.
Core and Builtins¶
bpo-44872: Use new trashcan macros (Py_TRASHCAN_BEGIN/END) in frameobject.c instead of the old ones (Py_TRASHCAN_SAFE_BEGIN/END).
bpo-33930: Fix segmentation fault with deep recursion when cleaning method objects. Patch by Augusto Goulart and Pablo Galindo.
bpo-44856: Fix reference leaks in the error paths of
update_bases()
and__build_class__
. Patch by Pablo Galindo.
Library¶
bpo-45001: Made email date parsing more robust against malformed input, namely a whitespace-only
Date:
header. Patch by Wouter Bolsterlee.
Documentation¶
bpo-30511: Clarify that
shutil.make_archive()
is not thread-safe due to reliance on changing the current working directory.
Windows¶
bpo-45007: Update to OpenSSL 1.1.1l in Windows build
macOS¶
bpo-45007: Update macOS installer builds to use OpenSSL 1.1.1l.
bpo-44689:
ctypes.util.find_library()
now works correctly on macOS 11 Big Sur even if Python is built on an older version of macOS. Previously, when built on older macOS systems,find_library
was not able to find macOS system libraries when running on Big Sur due to changes in how system libraries are stored.
Python 3.8.11 final¶
Release date: 2021-06-28
Security¶
bpo-44022: mod:
http.client
now avoids infinitely reading potential HTTP headers after a100 Continue
status response from the server.bpo-43882: The presence of newline or tab characters in parts of a URL could allow some forms of attacks.
Following the controlling specification for URLs defined by WHATWG
urllib.parse()
now removes ASCII newlines and tabs from URLs, preventing such attacks.bpo-42800: Audit hooks are now fired for frame.f_code, traceback.tb_frame, and generator code/frame attribute access.
Core and Builtins¶
bpo-44070: No longer eagerly makes import filenames absolute, except for extension modules, which was introduced in 3.8.10.
Library¶
bpo-44061: Fix regression in previous release when calling
pkgutil.iter_modules()
with a list ofpathlib.Path
objects
Python 3.8.10 final¶
Release date: 2021-05-03
Security¶
bpo-43434: Creating a
sqlite3.Connection
object now also produces asqlite3.connect
auditing event. Previously this event was only produced bysqlite3.connect()
calls. Patch by Erlend E. Aasland.bpo-43472: Ensures interpreter-level audit hooks receive the
cpython.PyInterpreterState_New
event when called through the_xxsubinterpreters
module.bpo-43075: Fix Regular Expression Denial of Service (ReDoS) vulnerability in
urllib.request.AbstractBasicAuthHandler
. The ReDoS-vulnerable regex has quadratic worst-case complexity and it allows cause a denial of service when identifying crafted invalid RFCs. This ReDoS issue is on the client side and needs remote attackers to control the HTTP server.
Core and Builtins¶
bpo-43105: Importlib now resolves relative paths when creating module spec objects from file locations.
bpo-42924: Fix
bytearray
repetition incorrectly copying data from the start of the buffer, even if the data is offset within the buffer (e.g. after reassigning a slice at the start of thebytearray
to a shorter byte string).
Library¶
bpo-43993: Update bundled pip to 21.1.1.
bpo-43937: Fixed the
turtle
module working with non-default root window.bpo-43930: Update bundled pip to 21.1 and setuptools to 56.0.0
bpo-43920: OpenSSL 3.0.0:
load_verify_locations()
now returns a consistent error message when cadata contains no valid certificate.bpo-43607:
urllib
can now convert Windows paths with\\?\
prefixes into URL paths.bpo-43284: platform.win32_ver derives the windows version from sys.getwindowsversion().platform_version which in turn derives the version from kernel32.dll (which can be of a different version than Windows itself). Therefore change the platform.win32_ver to determine the version using the platform module’s _syscmd_ver private function to return an accurate version.
bpo-42248: [Enum] ensure exceptions raised in
_missing__
are releasedbpo-43799: OpenSSL 3.0.0: define
OPENSSL_API_COMPAT
1.1.1 to suppress deprecation warnings. Python requires OpenSSL 1.1.1 APIs.bpo-43794: Add
ssl.OP_IGNORE_UNEXPECTED_EOF
constants (OpenSSL 3.0.0)bpo-43789: OpenSSL 3.0.0: Don’t call the password callback function a second time when first call has signaled an error condition.
bpo-43788: The header files for
ssl
error codes are now OpenSSL version-specific. Exceptions will now show correct reason and library codes. Themake_ssl_data.py
script has been rewritten to use OpenSSL’s text file with error codes.bpo-43655:
tkinter
dialog windows are now recognized as dialogs by window managers on macOS and X Window.bpo-43534:
turtle.textinput()
andturtle.numinput()
create now a transient window working on behalf of the canvas window.bpo-43522: Fix problem with
hostname_checks_common_name
. OpenSSL does not copy hostflags from struct SSL_CTX to struct SSL.bpo-42967: Allow
bytes
separator
argument inurllib.parse.parse_qs
andurllib.parse.parse_qsl
when parsingstr
query strings. Previously, this raised aTypeError
.bpo-43176: Fixed processing of a dataclass that inherits from a frozen dataclass with no fields. It is now correctly detected as an error.
bpo-34463: Fixed discrepancy between
traceback
and the interpreter in formatting of SyntaxError with lineno not set (traceback
was changed to match interpreter).bpo-41735: Fix thread locks in zlib module may go wrong in rare case. Patch by Ma Lin.
bpo-26053: Fixed bug where the
pdb
interactive run command echoed the args from the shell command line, even if those have been overridden at the pdb prompt.bpo-36470: Fix dataclasses with
InitVar
s andreplace()
. Patch by Claudiu Popa.bpo-28577: The hosts method on 32-bit prefix length IPv4Networks and 128-bit prefix IPv6Networks now returns a list containing the single Address instead of an empty list.
bpo-32745: Fix a regression in the handling of ctypes’
ctypes.c_wchar_p
type: embedded null characters would cause aValueError
to be raised. Patch by Zackery Spytz.
Documentation¶
bpo-43959: The documentation on the PyContextVar C-API was clarified.
bpo-43938: Update dataclasses documentation to express that FrozenInstanceError is derived from AttributeError.
bpo-43739: Fixing the example code in Doc/extending/extending.rst to declare and initialize the pmodule variable to be of the right type.
Tests¶
bpo-43842: Fix a race condition in the SMTP test of test_logging. Don’t close a file descriptor (socket) from a different thread while asyncore.loop() is polling the file descriptor. Patch by Victor Stinner.
bpo-43811: Tests multiple OpenSSL versions on GitHub Actions. Use ccache to speed up testing.
bpo-43791: OpenSSL 3.0.0: Disable testing of legacy protocols TLS 1.0 and 1.1. Tests are failing with TLSV1_ALERT_INTERNAL_ERROR.
Windows¶
bpo-35306: Avoid raising errors from
pathlib.Path.exists()
when passed an invalid filename.bpo-38822: Fixed
os.stat()
failing on inaccessible directories with a trailing slash, rather than falling back to the parent directory’s metadata. This implicitly affectedos.path.exists()
andos.path.isdir()
.bpo-26227: Fixed decoding of host names in
socket.gethostbyaddr()
andsocket.gethostbyname_ex()
.bpo-43745: Actually updates Windows release to OpenSSL 1.1.1k. Earlier releases were mislabelled and actually included 1.1.1i again.
bpo-43492: Upgrade Windows installer to use SQLite 3.35.5.
macOS¶
bpo-44009: Provide “python3.x-intel64” executable to allow reliably forcing macOS universal2 framework builds to run under Rosetta 2 Intel-64 emulation on Apple Silicon Macs. This can be useful for testing or when universal2 wheels are not yet available.
bpo-41100: As of 3.8.10, Python now supports building and running on macOS 11 (Big Sur) and on Apple Silicon Macs (based on the
ARM64
architecture). A new universal build variant,universal2
, is also available to natively support bothARM64
andIntel 64
in one set of executables. This backport from Python 3.9 does not include support for “weaklinking”; to support a range of macOS versions, continue to target for and build on the oldest version in the range; for 3.8.x, theuniversal2
variant is only useful on macOS 11 or later.bpo-43492: Update macOS installer to use SQLite 3.35.4.
IDLE¶
bpo-43655: IDLE dialog windows are now recognized as dialogs by window managers on macOS and X Window.
C API¶
bpo-43962: _PyInterpreterState_IDIncref() now calls _PyInterpreterState_IDInitref() and always increments id_refcount. Previously, calling _xxsubinterpreters.get_current() could create an id_refcount inconsistency when a _xxsubinterpreters.InterpreterID object was deallocated. Patch by Victor Stinner.
Python 3.8.9 final¶
Release date: 2021-04-02
Security¶
bpo-42988: CVE-2021-3426: Remove the
getfile
feature of thepydoc
module which could be abused to read arbitrary files on the disk (directory traversal vulnerability). Moreover, even source code of Python modules can contain sensitive data like passwords. Vulnerability reported by David Schwörer.bpo-43285:
ftplib
no longer trusts the IP address value returned from the server in response to the PASV command by default. This prevents a malicious FTP server from using the response to probe IPv4 address and port combinations on the client network.Code that requires the former vulnerable behavior may set a
trust_server_pasv_ipv4_address
attribute on theirftplib.FTP
instances toTrue
to re-enable it.bpo-43439: Add audit hooks for
gc.get_objects()
,gc.get_referrers()
andgc.get_referents()
. Patch by Pablo Galindo.
Core and Builtins¶
bpo-43660: Fix crash that happens when replacing
sys.stderr
with a callable that can remove the object while an exception is being printed. Patch by Pablo Galindo.bpo-35883: Python no longer fails at startup with a fatal error if a command line argument contains an invalid Unicode character. The
Py_DecodeLocale()
function now escapes byte sequences which would be decoded as Unicode characters outside the [U+0000; U+10ffff] range.bpo-43406: Fix a possible race condition where
PyErr_CheckSignals
tries to execute a non-Python signal handler.
Library¶
bpo-35930: Raising an exception raised in a “future” instance will create reference cycles.
bpo-43577: Fix deadlock when using
ssl.SSLContext
debug callback withssl.SSLContext.sni_callback()
.bpo-43423:
subprocess.communicate()
no longer raises an IndexError when there is an empty stdout or stderr IO buffer during a timeout on Windows.bpo-27820: Fixed long-standing bug of smtplib.SMTP where doing AUTH LOGIN with initial_response_ok=False will fail.
The cause is that SMTP.auth_login _always_ returns a password if provided with a challenge string, thus non-compliant with the standard for AUTH LOGIN.
Also fixes bug with the test for smtpd.
bpo-43399: Fix
ElementTree.extend
not working on iterators when using the Python implementationbpo-43316: The
python -m gzip
command line application now properly fails when detecting an unsupported extension. It exits with a non-zero exit code and prints an error message to stderr.bpo-43260: Fix TextIOWrapper can not flush internal buffer forever after very large text is written.
bpo-42782: Fail fast in
shutil.move()
to avoid creating destination directories on failure.bpo-37193: Fixed memory leak in
socketserver.ThreadingMixIn
introduced in Python 3.7.
Documentation¶
bpo-43199: Answer “Why is there no goto?” in the Design and History FAQ.
bpo-43407: Clarified that a result from
time.monotonic()
,time.perf_counter()
,time.process_time()
, ortime.thread_time()
can be compared with the result from any following call to the same function - not just the next immediate call.bpo-27646: Clarify that ‘yield from <expr>’ works with any iterable, not just iterators.
bpo-36346: Update some deprecated unicode APIs which are documented as “will be removed in 4.0” to “3.12”. See PEP 623 for detail.
Tests¶
Build¶
macOS¶
bpo-41837: Update macOS installer build to use OpenSSL 1.1.1j.
IDLE¶
bpo-42225: Document that IDLE can fail on Unix either from misconfigured IP masquerage rules or failure displaying complex colored (non-ascii) characters.
bpo-43283: Document why printing to IDLE’s Shell is often slower than printing to a system terminal and that it can be made faster by pre-formatting a single string before printing.
Python 3.8.8 final¶
Release date: 2021-02-19
There were no new changes in version 3.8.8.
Python 3.8.8 release candidate 1¶
Release date: 2021-02-16
Security¶
bpo-42967: Fix web cache poisoning vulnerability by defaulting the query args separator to
&
, and allowing the user to choose a custom separator.bpo-42938: Avoid static buffers when computing the repr of
ctypes.c_double
andctypes.c_longdouble
values.
Core and Builtins¶
bpo-42819:
readline
: Explicitly disable bracketed paste in the interactive interpreter, even if it’s set in the inputrc, is enabled by default (eg GNU Readline 8.1), or a user callsreadline.read_init_file()
. The Python REPL has not implemented bracketed paste support. Also, bracketed mode writes the"\x1b[?2004h"
escape sequence into stdout which causes test failures in applications that don’t support it. It can still be explicitly enabled by callingreadline.parse_and_bind("set enable-bracketed-paste on")
. Patch by Dustin Rodrigues.
Library¶
bpo-43108: Fixed a reference leak in the
curses
module. Patch by Pablo Galindobpo-42780: Fix os.set_inheritable() for O_PATH file descriptors on Linux.
bpo-41748: Fix HTMLParser parsing rules for element attributes containing commas with spaces. Patch by Karl Dubost.
bpo-42759: Fixed equality comparison of
tkinter.Variable
andtkinter.font.Font
. Objects which belong to different Tcl interpreters are now always different, even if they have the same name.bpo-23328: Allow / character in username, password fields on _PROXY envars.
bpo-42681: Fixed range checks for color and pair numbers in
curses
.bpo-42531:
importlib.resources.path()
now works for packages missing the optional__file__
attribute (more specifically, packages whose__spec__
.
origin
is
None
).bpo-42388: Fix subprocess.check_output(…, input=None) behavior when text=True to be consistent with that of the documentation and universal_newlines=True.
bpo-42384: Make pdb populate sys.path[0] exactly the same as regular python execution.
bpo-42383: Fix pdb: previously pdb would fail to restart the debugging target if it was specified using a relative path and the current directory changed.
bpo-42318: Fixed support of non-BMP characters in
tkinter
on macOS.bpo-42005: Fix CLI of
cProfile
andprofile
to catchBrokenPipeError
.bpo-41604: Don’t decrement the reference count of the previous user_ptr when set_panel_userptr fails.
bpo-26407: Unexpected errors in calling the
__iter__
method are no longer masked byTypeError
incsv.reader()
,csv.writer.writerow()
andcsv.writer.writerows()
.bpo-39068: Fix initialization race condition in
a85encode()
andb85encode()
inbase64
. Patch by Brandon Stansbury.bpo-36589: The
curses.update_lines_cols()
function now returnsNone
instead of1
on success.bpo-33289: Correct call to
tkinter.colorchooser
to return RGB triplet of ints instead of floats. Patch by Cheryl Sabella.
Documentation¶
Tests¶
Build¶
bpo-29076: Add fish shell support to macOS installer.
Windows¶
macOS¶
IDLE¶
bpo-43008: Make IDLE invoke
sys.excepthook()
in normal, 2-process mode. Patch by Ken Hilton.bpo-33065: Fix problem debugging user classes with __repr__ method.
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-23544: Disable Debug=>Stack Viewer when user code is running or Debugger is active, to prevent hang or crash. Patch by Zackery Spytz.
bpo-32631: Finish zzdummy example extension module: make menu entries work; add docstrings and tests with 100% coverage.
Tools/Demos¶
bpo-42726: Fixed Python 3 compatibility issue with gdb/libpython.py handling of attribute dictionaries.
C API¶
bpo-43030: Fixed a compiler warning in
Py_UNICODE_ISSPACE()
on platforms with signedwchar_t
.bpo-40052: Fix an alignment build warning/error in function
PyVectorcall_Function()
. Patch by Andreas Schneider, Antoine Pitrou and Petr Viktorin.
Python 3.8.7 final¶
Release date: 2020-12-21
Core and Builtins¶
bpo-32381: Fix encoding name when running a
.pyc
file on Windows:PyRun_SimpleFileExFlags()
now uses the correct encoding to decode the filename.bpo-42536: Several built-in and standard library types now ensure that their internal result tuples are always tracked by the garbage collector:
Previously, they could have become untracked by a prior garbage collection. Patch by Brandt Bucher.
Library¶
bpo-42630:
tkinter
functions and constructors which need a default root window raise nowRuntimeError
with descriptive message instead of obscureAttributeError
orNameError
if it is not created yet or cannot be created automatically.bpo-42644:
logging.disable
will now validate the types and value of its parameter. It also now accepts strings representing the levels (as doesloging.setLevel
) instead of only the numerical values.bpo-36541: Fixed lib2to3.pgen2 to be able to parse PEP-570 positional only argument syntax.
bpo-42375: subprocess module update for DragonFlyBSD support.
bpo-39825: Windows: Change
sysconfig.get_config_var('EXT_SUFFIX')
to the expected fullplatform_tag.extension
format. Previously it was hard-coded to.pyd
, now it is compatible withdistutils.sysconfig
and will result in something like.cp38-win_amd64.pyd
. This brings windows into conformance with the other platforms.bpo-39101: Fixed tests using IsolatedAsyncioTestCase from hanging on BaseExceptions.
bpo-41889: Enum: fix regression involving inheriting a multiply-inherited enum
bpo-41891: Ensure asyncio.wait_for waits for task completion
bpo-40219: Lowered
tkinter.ttk.LabeledScale
dummy widget to prevent hiding part of the content label.bpo-40084: Fix
Enum.__dir__
: dir(Enum.member) now includes attributes as well as methods.
Documentation¶
bpo-17140: Add documentation for the
multiprocessing.pool.ThreadPool
class.
Build¶
bpo-42604: Now all platforms use a value for the “EXT_SUFFIX” build variable derived from SOABI (for instance in freeBSD, “EXT_SUFFIX” is now “.cpython-310d.so” instead of “.so”). Previosuly only Linux, Mac and VxWorks were using a value for “EXT_SUFFIX” that included “SOABI”.
bpo-42598: Fix implicit function declarations in configure which could have resulted in incorrect configuration checks. Patch contributed by Joshua Root.
Tools/Demos¶
bpo-42613: Fix
freeze.py
tool to use the prope config and library directories. Patch by Victor Stinner.
Python 3.8.7 release candidate 1¶
Release date: 2020-12-07
Security¶
bpo-42103: Prevented potential DoS attack via CPU and RAM exhaustion when processing malformed Apple Property List files in binary format.
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.bpo-40791: Add
volatile
to the accumulator variable inhmac.compare_digest
, making constant-time-defeating optimizations less likely.
Core and Builtins¶
bpo-41686: On Windows, the
SIGINT
event,_PyOS_SigintEvent()
, is now created even if Python is configured to not install signal handlers (ifPyConfig.install_signal_handlers
equals to 0, orPy_InitializeEx(0)
).bpo-42143: Fix handling of errors during creation of
PyFunctionObject
, which resulted in operations on uninitialized memory. Patch by Yonatan Goldschmidt.bpo-41984: The garbage collector now tracks all user-defined classes. Patch by Brandt Bucher.
bpo-41909: Fixed stack overflow in
issubclass()
andisinstance()
when getting the__bases__
attribute leads to infinite recursion.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.
Library¶
bpo-17735:
inspect.findsource()
now raisesOSError
instead ofIndexError
whenco_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: Fix handling of trailing comments by
inspect.getsource()
.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-42406: We fixed an issue in
pickle.whichmodule
in which importingmultiprocessing
could change the how pickle identifies which module an object belongs to, potentially breaking the unpickling of those objects.bpo-42328: Fixed
tkinter.ttk.Style.map()
. The function accepts now the representation of the default state as empty sequence (as returned byStyle.map()
). The structure of the result is now the same on all platform and does not depend on the value ofwantobjects
.bpo-42014: The
onerror
callback fromshutil.rmtree
now receives correct function whenos.open
fails.bpo-42237: Fix
os.sendfile()
on illumos.bpo-42249: Fixed writing binary Plist files larger than 4 GiB.
bpo-35455: On Solaris,
thread_time()
is now implemented withgethrvtime()
becauseclock_gettime(CLOCK_THREAD_CPUTIME_ID)
is not always available. Patch by Jakub Kulik.bpo-41754: webbrowser: Ignore NotADirectoryError when calling
xdg-settings
.bpo-29566:
binhex.binhex()
consisently writes macOS 9 line endings.bpo-42183: Fix a stack overflow error for asyncio Task or Future repr().
The overflow occurs under some circumstances when a Task or Future recursively returns itself.
bpo-42103:
InvalidFileException
andRecursionError
are now the only errors caused by loading malformed binary Plist file (previously ValueError and TypeError could be raised in some specific cases).bpo-41491: plistlib: fix parsing XML plists with hexadecimal integer values
bpo-32498: Clearer exception message when passing an argument of type bytes to
urllib.parse.unquote()
. This is only for 3.8; in 3.9 and later this function accepts bytes inputs as well. PR by Irit Katriel.bpo-42065: Fix an incorrectly formatted error from
_codecs.charmap_decode()
when called with a mapped value outside the range of valid Unicode code points. PR by Max Bernstein.bpo-41966: Fix pickling pure Python
datetime.time
subclasses. Patch by Dean Inwood.bpo-41976: Fixed a bug that was causing
ctypes.util.find_library()
to returnNone
when triying to locate a library in an environment when gcc>=9 is available andldconfig
is not. Patch by Pablo Galindobpo-41900: C14N 2.0 serialisation in xml.etree.ElementTree failed for unprefixed attributes when a default namespace was defined.
bpo-41855: In
importlib.metadata
, fix issue where multiple children can be returned fromFastPath.zip_children()
. Backport of python-devs/importlib_metadata#117.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-41831:
str()
for thetype
attribute of thetkinter.Event
object always returns now the numeric code returned by Tk instead of the name of the event type.bpo-41662: No longer override exceptions raised in
__len__()
of a sequence of parameters insqlite3
withProgrammingError
.bpo-41662: Fixed crash when mutate list of parameters during iteration in
sqlite3
.bpo-34215: Clarify the error message for
asyncio.IncompleteReadError
whenexpected
isNone
.bpo-41316: Fix the
tarfile
module to write only basename of TAR file to GZIP compression header.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-16936: Allow
ctypes.wintypes
to be imported on non-Windows systems.bpo-40592:
shutil.which()
now ignores empty entries inPATHEXT
instead of treating them as a match.bpo-40492: Fix
--outfile
forcProfile
/profile
not writing the output file in the original directory when the program being profiled changes the working directory. PR by Anthony Sottile.bpo-40105: ZipFile truncates files to avoid corruption when a shorter comment is provided in append (“a”) mode. Patch by Jan Mazur.
bpo-27321: Fixed KeyError exception when flattening an email to a string attempts to replace a non-existent Content-Transfer-Encoding header.
bpo-32793: Fix a duplicated debug message when
smtplib.SMTP.connect()
is called.
Documentation¶
bpo-42153: Fix the URL for the IMAP protocol documents.
bpo-41910: Document the default implementation of
object.__eq__
.bpo-41774: In Programming FAQ “Sequences (Tuples/Lists)” section, add “How do you remove multiple items from a list”.
bpo-39416: Document some restrictions on the default string representations of numeric classes.
Tests¶
bpo-41473: Reenable 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: Fix
test_asyncio.test_call_later()
race condition: don’t measure asyncio performance in thecall_later()
unit test. The test failed randomly on the CI.bpo-40754: Include
_testinternalcapi
module in Windows installer for test suitebpo-41739: Fix test_logging.test_race_between_set_target_and_flush(): the test now waits until all threads complete to avoid leaking running threads.
bpo-41944: Tests for CJK codecs no longer call
eval()
on content received via HTTP.bpo-41939: Fix test_site.test_license_exists_at_url(): call
urllib.request.urlcleanup()
to reset the globalurllib.request._opener
. Patch by Victor Stinner.bpo-41561: test_ssl: skip test_min_max_version_mismatch when TLS 1.0 is not available
bpo-41602: Add tests for SIGINT handling in the runpy module.
bpo-41306: Fixed a failure in
test_tk.test_widgets.ScaleTest
happening when executing the test with Tk 8.6.10.
Build¶
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.
Windows¶
macOS¶
IDLE¶
bpo-42426: Fix reporting offset of the RE error in searchengine.
bpo-42415: Get docstrings for IDLE calltips more often by using inspect.getdoc.
bpo-33987: Mostly finish using ttk widgets, mainly for editor, settings, and searches. Some patches by Mark Roseman.
bpo-41775: Use ‘IDLE Shell’ as shell title
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 call-tip, e.g. when typed in a string literal.
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-41986:
Py_FileSystemDefaultEncodeErrors
andPy_UTF8Mode
are available again in limited API.
Python 3.8.6 final¶
Release date: 2020-09-23
Core and Builtins¶
bpo-41525: The output of
python --help
contains now only ASCII characters.
Library¶
bpo-41817: fix
tkinter.EventType
Enum so all members are strings, and none are tuplesbpo-41815: Fix SQLite3 segfault when backing up closed database. Patch contributed by Peter David McCormick.
bpo-41517: fix bug allowing Enums to be extended via multiple inheritance
bpo-39587: use the correct mix-in data type when constructing Enums
bpo-41789: Honor
object
overrides inEnum
class creation (specifically,__str__
,__repr__
,__format__
, and__reduce_ex__
).bpo-39651: Fix a race condition in the
call_soon_threadsafe()
method ofasyncio.ProactorEventLoop
: do nothing if the self-pipe socket has been closed.bpo-41720: Fixed
turtle.Vec2D.__rmul__()
for arguments which are not int or float.bpo-39728: fix default
_missing_
so a duplicateValueError
is not set as the__context__
of the originalValueError
bpo-37479: When
Enum.__str__
is overridden in a derived class, the override will be used byEnum.__format__
regardless of whether mixin classes are present.
Documentation¶
Tests¶
bpo-41731: Make test_cmd_line_script pass with option ‘-vv’.
Windows¶
bpo-41744: Fixes automatic import of props file when using the Nuget package.
IDLE¶
Python 3.8.6 release candidate 1¶
Release date: 2020-09-07
Core and Builtins¶
bpo-41654: Fix a crash that occurred when destroying subclasses of
MemoryError
. Patch by Pablo Galindo.bpo-41533: Free the stack allocated in
va_build_stack
ifdo_mkstack
fails and the stack is not asmall_stack
.bpo-38156: Handle interrupts that come after EOF correctly in
PyOS_StdioReadline
.
Library¶
bpo-41696: Fix handling of debug mode in
asyncio.run()
. This allows settingPYTHONASYNCIODEBUG
or-X dev
to enable asyncio debug mode when usingasyncio.run()
.bpo-39010: Restarting a
ProactorEventLoop
on Windows no longer logs spuriousConnectionResetErrors
.bpo-41609: The pdb whatis command correctly reports instance methods as ‘Method’ rather than ‘Function’.
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:
asyncio.wait_for()
now properly handles races between cancellation of itself and the completion of the wrapped awaitable.bpo-40782: Change the method asyncio.AbstractEventLoop.run_in_executor to not be a coroutine.
bpo-41520: Fix
codeop
regression that prevented turning compile warnings into errors.bpo-41503: Fixed a race between setTarget and flush in logging.handlers.MemoryHandler.
bpo-41497: Fix potential UnicodeDecodeError in dis module.
bpo-41490: Update
ensurepip
to install pip 20.2.1 and setuptools 49.2.1.bpo-41467: On Windows, fix asyncio
recv_into()
return value when the socket/pipe is closed (BrokenPipeError
): return0
rather than an empty byte string (b''
).bpo-41425: Make tkinter doc example runnable.
bpo-41384: Raise TclError instead of TypeError when an unknown option is passed to tkinter.OptionMenu.
bpo-38731: Fix
NameError
in command-line interface ofpy_compile
.bpo-41344: Prevent creating
shared_memory.SharedMemory
objects withsize=0
.bpo-40726: Handle cases where the
end_lineno
isNone
onast.increment_lineno()
.bpo-31122: ssl.wrap_socket() now raises ssl.SSLEOFError rather than OSError when peer closes connection during TLS negotiation
bpo-33660: Fix pathlib.PosixPath to resolve a relative path located on the root directory properly.
Documentation¶
bpo-41624: Fix the signature of
typing.Coroutine
.bpo-40204: Enable Sphinx 3.2
c_allow_pre_v3
option and disablec_warn_on_allowed_pre_v3
option to make the documentation compatible with Sphinx 2 and Sphinx 3.bpo-41045: Add documentation for debug feature of f-strings.
bpo-41314: Changed the release when
from __future__ import annotations
becomes the default from4.0
to3.10
(following a change in PEP 563).bpo-39883: Make code, examples, and recipes in the Python documentation be licensed under the more permissive BSD0 license in addition to the existing Python 2.0 license.
Windows¶
IDLE¶
C API¶
bpo-41524: Fix bug in PyOS_mystrnicmp and PyOS_mystricmp that incremented pointers beyond the end of a string.
Python 3.8.5 final¶
Release date: 2020-07-20
Security¶
Core and Builtins¶
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.
Library¶
Documentation¶
bpo-37703: Updated Documentation to comprehensively elaborate on the behaviour of gather.cancel()
Build¶
bpo-41302: Enable building Python 3.8 with libmpdec-2.5.0 to ease maintenance for Linux distributions. Patch by Felix Yan.
macOS¶
bpo-40741: Update macOS installer to use SQLite 3.32.3.
IDLE¶
bpo-41300: Save files with non-ascii chars. Fix regression released in 3.9.0b4 and 3.8.4.
Python 3.8.4 final¶
Release date: 2020-07-13
Security¶
Core and Builtins¶
bpo-41247: Always cache the running loop holder when running
asyncio.set_running_loop
.bpo-41252: Fix incorrect refcounting in _ssl.c’s
_servername_callback()
.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-41175: Guard against a NULL pointer dereference within bytearrayobject triggered by the
bytearray() + bytearray()
operation.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.
Library¶
bpo-41235: Fix the error handling in
ssl.SSLContext.load_dh_params()
.bpo-41193: The
write_history()
atexit function of the readline completer now ignores anyOSError
to ignore error if the filesystem is read-only, instead of only ignoringFileNotFoundError
andPermissionError
.bpo-41043: Fixed the use of
glob()
in the stdlib: literal part of the path is now always correctly escaped.bpo-39384: Fixed email.contentmanager to allow set_content() to set a null string.
IDLE¶
Python 3.8.4 release candidate 1¶
Release date: 2020-06-29
Security¶
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-39073: Disallow CR or LF in email.headerregistry.Address arguments to guard against header injection attacks.
Core and Builtins¶
bpo-41094: Fix decoding errors with audit when open files with non-ASCII names on non-UTF-8 locale.
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-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-40957: Fix refleak in _Py_fopen_obj() when PySys_Audit() fails
bpo-40870: Raise
ValueError
when validating custom AST’s where the constantsTrue
,False
andNone
are used within aast.Name
node.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-40824: Unexpected errors in calling the
__iter__
method are no longer masked byTypeError
in thein
operator and functionscontains()
,indexOf()
andcountOf()
of theoperator
module.bpo-40663: Correctly generate annotations where parentheses are omitted but required (e.g:
Type[(str, int, *other))]
.
Library¶
bpo-41138: Fixed the
trace
module CLI for Python source files with non-UTF-8 encoding.bpo-31938: Fix default-value signatures of several functions in the
select
module - by Anthony Sottile.bpo-41068: Fixed reading files with non-ASCII names from ZIP archive directly after writing them.
bpo-41058:
pdb.find_function()
now correctly determines the source file encoding.bpo-41056: Fix a NULL pointer dereference within the ssl module during a MemoryError in the keylog callback. (discovered by Coverity)
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-40448:
ensurepip
now disables the use ofpip
cache when installing the bundled versions ofpip
andsetuptools
. Patch by Krzysztof Konopko.bpo-40855: The standard deviation and variance functions in the statistics module were ignoring their mu and xbar arguments.
bpo-40807: Stop codeop._maybe_compile, used by code.InteractiveInterpreter (and IDLE). from from emitting each warning three times.
bpo-40834: Fix truncate when sending str object with_xxsubinterpreters.channel_send.
bpo-38488: Update ensurepip to install pip 20.1.1 and setuptools 47.1.0.
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-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 byPyErr_Print()
.bpo-30008: Fix
ssl
code to be compatible with OpenSSL 1.1.x builds that useno-deprecated
and--api=1.1.0
.bpo-40614:
ast.parse()
will not parse self documenting expressions in f-strings when passedfeature_version
is less than(3, 8)
.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-25872:
linecache
could crash with aKeyError
when accessed from multiple threads. Fix by Michael Graczyk.bpo-40597: If text content lines are longer than policy.max_line_length, always use a content-encoding to make sure they are wrapped.
bpo-40515: The
ssl
andhashlib
modules now actively check that OpenSSL is build with thread support. Python 3.7.0 made thread support mandatory and no longer works safely with a no-thread builds.bpo-13097:
ctypes
now raises anArgumentError
when a callback is invoked with more than 1024 arguments.bpo-40457: The ssl module now support OpenSSL builds without TLS 1.0 and 1.1 methods.
bpo-39830: Add
zipfile.Path
to__all__
in thezipfile
module.bpo-40025: Raise TypeError when _generate_next_value_ is defined after members. Patch by Ethan Onstott.
bpo-39244: Fixed
multiprocessing.context.get_all_start_methods
to properly return the default method first on macOS.bpo-39040: Fix parsing of invalid mime headers parameters by collapsing whitespace between encoded words in a bare-quote-string.
bpo-35714:
struct.error
is now raised if there is a null character in astruct
format string.bpo-36290: AST nodes are now raising
TypeError
on conflicting keyword arguments. Patch contributed by Rémi Lapeyre.bpo-29620:
assertWarns()
no longer raises aRuntimeException
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-34226: Fix
cgi.parse_multipart
without content_length. Patch by Roger Duran
Tests¶
bpo-41085: Fix integer overflow in the
array.array.index()
method on 64-bit Windows for index larger than2**31
.bpo-38377: On Linux, skip tests using multiprocessing if the current user cannot create a file in
/dev/shm/
directory. Add theskip_if_broken_multiprocessing_synchronize()
function to thetest.support
module.bpo-41009: Fix use of
support.require_{linux|mac|freebsd}_version()
decorators as class decorator.bpo-41003: Fix
test_copyreg
whennumpy
is installed:test.pickletester
now saves/restores warnings filters when importingnumpy
, to ignore filters installed bynumpy
.bpo-40964: Disable remote
imaplib
tests, host cyrus.andrew.cmu.edu is blocking incoming connections.bpo-40055: distutils.tests now saves/restores warnings filters to leave them unchanged. Importing tests imports docutils which imports pkg_resources which adds a warnings filter.
bpo-34401: Make test_gdb properly run on HP-UX. Patch by Michael Osipov.
Build¶
Windows¶
bpo-41074: Fixed support of non-ASCII names in functions
msilib.OpenDatabase()
andmsilib.init_database()
and non-ASCII SQL in methodmsilib.Database.OpenView()
.bpo-40164: Updates Windows OpenSSL to 1.1.1g
bpo-39631: Changes the registered MIME type for
.py
files on Windows totext/x-python
instead oftext/plain
.bpo-40677: Manually define IO_REPARSE_TAG_APPEXECLINK in case some old Windows SDK doesn’t have it.
bpo-40650: Include winsock2.h in pytime.c for timeval.
bpo-39148: Add IPv6 support to
asyncio
datagram endpoints in ProactorEventLoop. Change the raised exception for unknown address families to ValueError as it’s not coming from Windows API.
macOS¶
bpo-39580: Avoid opening Finder window if running installer from the command line. Patch contributed by Rick Heil.
bpo-41100: Fix configure error when building on macOS 11. Note that the current Python release was released shortly after the first developer preview of macOS 11 (Big Sur); there are other known issues with building and running on the developer preview. Big Sur is expected to be fully supported in a future bugfix release of Python 3.8.x and with 3.9.0.
bpo-41005: fixed an XDG settings issue not allowing macos to open browser in webbrowser.py
bpo-40741: Update macOS installer to use SQLite 3.32.2.
IDLE¶
Tools/Demos¶
Python 3.8.3 final¶
Release date: 2020-05-13
Core and Builtins¶
bpo-40527: Fix command line argument parsing: no longer write errors multiple times into stderr.
bpo-40417: Fix imp module deprecation warning when PyImport_ReloadModule is called. Patch by Robert Rouhani.
bpo-39562: The constant values of future flags in the
__future__
module are updated in order to prevent collision with compiler flags. PreviouslyPyCF_ALLOW_TOP_LEVEL_AWAIT
was clashing withCO_FUTURE_DIVISION
.
Library¶
bpo-40559: Fix possible memory leak in the C implementation of
asyncio.Task
.bpo-40355: Improve error reporting in
ast.literal_eval()
in the presence of malformedast.Dict
nodes instead of silently ignoring any non-conforming elements. Patch by Curtis Bucher.bpo-40459:
platform.win32_ver()
now produces correct ptype strings instead of empty strings.bpo-40398:
typing.get_args()
now always returns an empty tuple for special generic aliases.
Documentation¶
bpo-40561: Provide docstrings for webbrowser open functions.
bpo-39435: Fix an incorrect signature for
pickle.loads()
in the docs
Windows¶
bpo-40458: Increase reserved stack space to prevent overflow crash on Windows.
C API¶
bpo-40412: Nullify inittab_copy during finalization, preventing future interpreter initializations in an embedded situation from crashing. Patch by Gregory Szorc.
Python 3.8.3 release candidate 1¶
Release date: 2020-04-29
Security¶
bpo-40121: Fixes audit events raised on creating a new socket.
bpo-38576: Disallow control characters in hostnames in http.client, addressing CVE-2019-18348. Such potentially malicious header injection URLs now cause a InvalidURL to be raised.
bpo-39503: CVE-2020-8492: The
AbstractBasicAuthHandler
class of theurllib.request
module uses an inefficient regular expression which can be exploited by an attacker to cause a denial of service. Fix the regex to prevent the catastrophic backtracking. Vulnerability reported by Ben Caller and Matt Schwager.
Core and Builtins¶
bpo-20526: Fix
PyThreadState_Clear()
.PyThreadState.frame
is a borrowed reference, not a strong reference:PyThreadState_Clear()
must not callPy_CLEAR(tstate->frame)
.bpo-39965: Correctly raise
SyntaxError
if await is used inside non-async functions andPyCF_ALLOW_TOP_LEVEL_AWAIT
is set (like in the asyncio REPL). Patch by Pablo Galindo.bpo-39562: Allow executing asynchronous comprehensions on the top level when the
PyCF_ALLOW_TOP_LEVEL_AWAIT
flag is given. Patch by Batuhan Taskaya.bpo-38894: Fix a bug that was causing incomplete results when calling
pathlib.Path.glob
in the presence of symlinks that point to files where the user does not have read access. Patch by Pablo Galindo and Matt Wozniski.bpo-39871: Fix a possible
SystemError
inmath.{atan2,copysign,remainder}()
when the first argument cannot be converted to afloat
. Patch by Zackery Spytz.bpo-39776: Fix race condition where threads created by PyGILState_Ensure() could get a duplicate id.
This affects consumers of tstate->id like the contextvar caching machinery, which could return invalid cached objects under heavy thread load (observed in embedded scenarios).
bpo-39778: Fixed a crash due to incorrect handling of weak references in
collections.OrderedDict
classes. Patch by Pablo Galindo.bpo-39520: Fix unparsing of ext slices with no items (
foo[:,]
). Patch by Batuhan Taskaya.bpo-22490: Don’t leak environment variable
__PYVENV_LAUNCHER__
into the interpreter session on macOS.
Library¶
bpo-40138: Fix the Windows implementation of
os.waitpid()
for exit code larger thanINT_MAX >> 8
. The exit status is now interpreted as an unsigned number.bpo-39942: Set “__main__” as the default module name when “__name__” is missing in
typing.TypeVar
. Patch by Weipeng Hong.bpo-40330: In
ShareableList.__setitem__()
, check the size of a new string item after encoding it to utf-8, not before.bpo-40287: Fixed
SpooledTemporaryFile.seek()
to return the position.bpo-40260: Ensure
modulefinder
usesio.open_code()
and respects coding comments.bpo-40196: Fix a bug in the
symtable
module that was causing incorrectly report global variables as local. Patch by Pablo Galindo.bpo-40126: Fixed reverting multiple patches in unittest.mock. Patcher’s
__exit__()
is now never called if its__enter__()
is failed. Returning true from__exit__()
silences now the exception.bpo-40089: Fix threading._after_fork(): if fork was not called by a thread spawned by threading.Thread, threading._after_fork() now creates a _MainThread instance for _main_thread, instead of a _DummyThread instance.
bpo-39503:
AbstractBasicAuthHandler
ofurllib.request
now parses all WWW-Authenticate HTTP headers and accepts multiple challenges per header: use the realm of the first Basic challenge.bpo-40014: Fix
os.getgrouplist()
: ifgetgrouplist()
function fails because the group list is too small, retry with a larger group list. On failure, the glibc implementation ofgetgrouplist()
setsngroups
to the total number of groups. For other implementations, double the group list size.bpo-40016: In re docstring, clarify the relationship between inline and argument compile flags.
bpo-39953: Update internal table of OpenSSL error codes in the
ssl
module.bpo-39360: Ensure all workers exit when finalizing a
multiprocessing.Pool
implicitly via the module finalization handlers of multiprocessing. This fixes a deadlock situation that can be experienced when the Pool is not properly finalized via the context manager or a call tomultiprocessing.Pool.terminate
. Patch by Batuhan Taskaya and Pablo Galindo.bpo-39652: The column name found in
sqlite3.Cursor.description
is now truncated on the first ‘[’ only if the PARSE_COLNAMES option is set.bpo-39915: Ensure
unittest.mock.AsyncMock.await_args_list
has call objects in the order of awaited arguments instead of usingunittest.mock.Mock.call_args
which has the last value of the call. Patch by Karthikeyan Singaravelan.bpo-38662: The
ensurepip
module now invokespip
via therunpy
module. Hence it is no longer tightly coupled with the internal API of the bundledpip
version, allowing easier updates to a newerpip
version both internally and for distributors.bpo-39916: More reliable use of
os.scandir()
inPath.glob()
. It no longer emits a ResourceWarning when interrupted.bpo-39850:
multiprocessing
now supports abstract socket addresses (if abstract sockets are supported in the running platform). Patch by Pablo Galindo.bpo-39828: Fix
json.tool
to catchBrokenPipeError
. Patch by Dong-hee Na.bpo-13487: Avoid a possible “RuntimeError: dictionary changed size during iteration” from
inspect.getmodule()
when it tried to loop throughsys.modules
.bpo-39794: Add –without-decimal-contextvar build option. This enables a thread-local rather than a coroutine local context.
bpo-39769: The
compileall.compile_dir()
function’s ddir parameter and the compileall command line flag-d
no longer write the wrong pathname to the generated pyc file for submodules beneath the root of the directory tree being compiled. This fixes a regression introduced with Python 3.5.bpo-39517: Fix runpy.run_path() when using pathlike objects
bpo-39764: Fix AttributeError when calling get_stack on a PyAsyncGenObject Task
bpo-30566: Fix
IndexError
when trying to decode an invalid string with punycode codec.bpo-39667: Correct performance degradation in
zipfile.Path
as found in zipp 3.0. While retaining compatibility, this change discourages the use ofzipfile.Path.open
due to the signature change in Python 3.9. For compatibility across Python 3.8 and later versions, consider usingzipp.Path
on Python 3.8.x and earlier.bpo-39548: Fix handling of header in
urllib.request.AbstractDigestAuthHandler
when the optionalqop
parameter is not present.bpo-38971: Open issue in the BPO indicated a desire to make the implementation of codecs.open() at parity with io.open(), which implements a try/except to assure file stream gets closed before an exception is raised.
bpo-38410: Properly handle
sys.audit()
failures insys.set_asyncgen_hooks()
. Based on patch by Zackery Spytz.bpo-36541: lib2to3 now recognizes named assignment expressions (the walrus operator,
:=
)bpo-31758: Prevent crashes when using an uninitialized
_elementtree.XMLParser
object. Patch by Oren Milman.
Documentation¶
bpo-27635: The pickle documentation incorrectly claimed that
__new__
isn’t called by default when unpickling.bpo-39879: Updated Modelo de dados docs to include
dict()
insertion order preservation. Patch by Furkan Onder and Samy Lahfa.bpo-13790: Change ‘string’ to ‘specification’ in format doc.
bpo-17422: The language reference no longer restricts default class namespaces to dicts only.
bpo-39530: Fix misleading documentation about mixed-type numeric comparisons.
bpo-39718: Update
token
documentation to reflect additions in Python 3.8bpo-39677: Changed operand name of MAKE_FUNCTION from argc to flags for module
dis
bpo-38387: Document
PyDoc_STRVAR
macro in the C-API reference.
Tests¶
bpo-40436: test_gdb and test.pythoninfo now check gdb command exit code.
bpo-40162: Update Travis CI configuration to OpenSSL 1.1.1f.
bpo-40146: Update OpenSSL to 1.1.1f in Azure Pipelines.
bpo-40019: test_gdb now skips tests if it detects that gdb failed to read debug information because the Python binary is optimized.
bpo-27807:
test_site.test_startup_imports()
is now skipped if a path ofsys.path
contains a.pth
file.bpo-39793: Use the same domain when testing
make_msgid
. Patch by Batuhan Taskaya.bpo-1812: Fix newline handling in doctest.testfile when loading from a package whose loader has a get_data method. Patch by Peter Donis.
bpo-37957: test.regrtest now can receive a list of test patterns to ignore (using the -i/–ignore argument) or a file with a list of patterns to ignore (using the –ignore-file argument). Patch by Pablo Galindo.
bpo-38502: test.regrtest now uses process groups in the multiprocessing mode (-jN command line option) if process groups are available: if
os.setsid()
andos.killpg()
functions are available.
Build¶
bpo-38360: Support single-argument form of macOS -isysroot flag.
bpo-40204: Pin Sphinx version to 1.8.2 in
Doc/Makefile
.bpo-40158: Fix CPython MSBuild Properties in NuGet Package (build/native/python.props)
bpo-38527: Fix configure check on Solaris for “float word ordering”: sometimes, the correct “grep” command was not being used. Patch by Arnon Yaari.
Windows¶
bpo-40164: Updates Windows to OpenSSL 1.1.1f
bpo-39930: Ensures the required
vcruntime140.dll
is included in install packages.bpo-39847: Avoid hang when computer is hibernated whilst waiting for a mutex (for lock-related objects from
threading
) around 49-day uptime.bpo-38597:
distutils
will no longer statically linkvcruntime140.dll
when a redistributable version is unavailable. All future releases of CPython will include a copy of this DLL to ensure distributed extensions can continue to load.bpo-38380: Update Windows builds to use SQLite 3.31.1
bpo-39789: Update Windows release build machines to Visual Studio 2019 (MSVC 14.2).
bpo-34803: Package for nuget.org now includes repository reference and bundled icon image.
macOS¶
IDLE¶
bpo-27115: For ‘Go to Line’, use a Query box subclass with IDLE standard behavior and improved error checking.
bpo-39885: Since clicking to get an IDLE context menu moves the cursor, any text selection should be and now is cleared.
bpo-39852: Edit “Go to line” now clears any selection, preventing accidental deletion. It also updates Ln and Col on the status bar.
bpo-39781: Selecting code context lines no longer causes a jump.
bpo-38439: Add a 256×256 pixel IDLE icon to support more modern environments. Created by Andrew Clover. Delete the unused macOS idle.icns icon file.
bpo-38689: IDLE will no longer freeze when inspect.signature fails when fetching a calltip.
Tools/Demos¶
bpo-40179: Fixed translation of
#elif
in Argument Clinic.bpo-36184: Port python-gdb.py to FreeBSD. python-gdb.py now checks for “take_gil” function name to check if a frame tries to acquire the GIL, instead of checking for “pthread_cond_timedwait” which is specific to Linux and can be a different condition than the GIL.
bpo-39889: Fixed
unparse.py
for extended slices containing a single element (e.g.a[i:j,]
). Remove redundant tuples when index with a tuple (e.g.a[i, j]
).
C API¶
bpo-35370: If
PySys_Audit()
fails inPyEval_SetProfile()
orPyEval_SetTrace()
, log the error as an unraisable exception.bpo-39884:
PyDescr_NewMethod()
andPyCFunction_NewEx()
now include the method name in the SystemError “bad call flags” error message to ease debug.bpo-38643:
PyNumber_ToBase()
now raises aSystemError
instead of crashing when called with invalid base.bpo-38913: Fixed segfault in
Py_BuildValue()
called with a format containing “#” and undefined PY_SSIZE_T_CLEAN whwn an exception is set.
Python 3.8.2 final¶
Release date: 2020-02-24
Core and Builtins¶
bpo-39382: Fix a use-after-free in the single inheritance path of
issubclass()
, when the__bases__
of an object has a single reference, and so does its first item. Patch by Yonatan Goldschmidt.bpo-39427: Document all possibilities for the
-X
options in the command line help section. Patch by Pablo Galindo.
Library¶
bpo-39649: Remove obsolete check for
__args__
in bdb.Bdb.format_stack_entry.bpo-39681: Fix a regression where the C pickle module wouldn’t allow unpickling from a file-like object that doesn’t expose a readinto() method.
bpo-39546: Fix a regression in
ArgumentParser
whereallow_abbrev=False
was ignored for long options that used a prefix character other than “-“.bpo-39432: Implement PEP-489 algorithm for non-ascii “PyInit_…” symbol names in distutils to make it export the correct init symbol also on Windows.
Documentation¶
bpo-17422: The language reference now specifies restrictions on class namespaces. Adapted from a patch by Ethan Furman.
bpo-39572: Updated documentation of
total
flag of TypeDict.bpo-39654: In pyclbr doc, update ‘class’ to ‘module’ where appropriate and add readmodule comment. Patch by Hakan Çelik.
IDLE¶
bpo-39663: Add tests for pyparse find_good_parse_start().
Python 3.8.2 release candidate 2¶
Release date: 2020-02-17
Security¶
Core and Builtins¶
bpo-39619: Enable use of
os.chroot()
on HP-UX systems.bpo-39606: Fix regression caused by fix for bpo-39386, that prevented calling
aclose
on an async generator that had already been closed or exhausted.bpo-39453: Fixed a possible crash in
list.__contains__()
when a list is changed during comparing items. Patch by Dong-hee Na.bpo-39219: Syntax errors raised in the tokenizer now always set correct “text” and “offset” attributes.
Library¶
bpo-27657: The original fix for bpo-27657, “Fix urlparse() with numeric paths” (PR 16839) included in 3.8.1, inadvertently introduced a behavior change that broke several third-party packages relying on the original undefined parsing behavior. The change is reverted in 3.8.2, restoring the behavior of 3.8.0 and earlier releases.
bpo-39474: Fixed starting position of AST for expressions like
(a)(b)
,(a)[b]
and(a).b
.bpo-21016: The
pydoc
andtrace
modules now use thesysconfig
module to get the path to the Python standard library, to support uncommon installation path like/usr/lib64/python3.9/
on Fedora. Patch by Jan Matějek.bpo-39595: Improved performance of zipfile.Path for files with a large number of entries. Also improved performance and fixed minor issue as published with importlib_metadata 1.5.
IDLE¶
bpo-39600: In the font configuration window, remove duplicated font names.
Python 3.8.2 release candidate 1¶
Release date: 2020-02-10
Security¶
Core and Builtins¶
bpo-39579: Change the ending column offset of
Attribute
nodes constructed inast_for_dotted_name
to point at the end of the current node and not at the end of the lastNAME
node.bpo-39510: Fix segfault in
readinto()
method on closed BufferedReader.bpo-39492: Fix a reference cycle in the C Pickler that was preventing the garbage collection of deleted, pickled objects.
bpo-39421: Fix possible crashes when operating with the functions in the
heapq
module and custom comparison operators.bpo-39386: Prevent double awaiting of async iterator.
bpo-39235: Fix AST end location for lone generator expression in function call, e.g. f(i for i in a).
bpo-39209: Correctly handle multi-line tokens in interactive mode. Patch by Pablo Galindo.
bpo-39216: Fix constant folding optimization for positional only arguments - by Anthony Sottile.
bpo-39215: Fix
SystemError
when nested function has annotation on positional-only argument - by Anthony Sottile.bpo-38588: Fix possible crashes in dict and list when calling
PyObject_RichCompareBool()
.bpo-38610: Fix possible crashes in several list methods by holding strong references to list elements when calling
PyObject_RichCompareBool()
.
Library¶
bpo-39590: Collections.deque now holds strong references during deque.__contains__ and deque.count, fixing crashes.
bpo-38149:
sys.audit()
is now called only once per call ofglob.glob()
andglob.iglob()
.bpo-39450: Striped whitespace from docstring before returning it from
unittest.case.shortDescription()
.bpo-39493: Mark
typing.IO.closed
as a propertybpo-39485: Fix a bug in
unittest.mock.create_autospec()
that would complain about the wrong number of arguments for custom descriptors defined in an extension module returning functions.bpo-39082: Allow AsyncMock to correctly patch static/class methods
bpo-39390: Fixed a regression with the
ignore
callback ofshutil.copytree()
. The argument types are now str and List[str] again.bpo-39389: Write accurate compression level metadata in
gzip
archives, rather than always signaling maximum compression.bpo-39274:
bool(fraction.Fraction)
now returns a boolean even if (numerator != 0) does not return a boolean (ex: numpy number).bpo-39297: Improved performance of importlib.metadata distribution discovery and resilients to inaccessible sys.path entries (importlib_metadata v1.4.0).
bpo-39242: Updated the Gmane domain from news.gmane.org to news.gmane.io which is used for examples of
NNTP
news reader server and nntplib tests.bpo-38907: In http.server script, restore binding to IPv4 on Windows.
bpo-39152: Fix ttk.Scale.configure([name]) to return configuration tuple for name or all options. Giovanni Lombardo contributed part of the patch.
bpo-39198: If an exception were to be thrown in
Logger.isEnabledFor
(say, by asyncio timeouts or stopit) , thelogging
global lock may not be released appropriately, resulting in deadlock. This change wraps that block of code withtry...finally
to ensure the lock is released.bpo-39191: Perform a check for running loop before starting a new task in
loop.run_until_complete()
to fail fast; it prevents the side effect of new task spawning before exception raising.bpo-38871: Correctly parenthesize filter-based statements that contain lambda expressions in mod:
lib2to3
. Patch by Dong-hee Na.bpo-39142: A change was made to logging.config.dictConfig to avoid converting instances of named tuples to ConvertingTuple. It’s assumed that named tuples are too specialised to be treated like ordinary tuples; if a user of named tuples requires ConvertingTuple functionality, they will have to implement that themselves in their named tuple class.
bpo-39129: Fix import path for
asyncio.TimeoutError
bpo-39057:
urllib.request.proxy_bypass_environment()
now ignores leading dots and no longer ignores a trailing newline.bpo-39056: Fixed handling invalid warning category in the -W option. No longer import the re module if it is not needed.
bpo-39055:
base64.b64decode()
withvalidate=True
raises now a binascii.Error if the input ends with a single\n
.bpo-39033: Fix
NameError
inzipimport
. Patch by Karthikeyan Singaravelan.bpo-38878: Fixed __subclasshook__ of
os.PathLike
to return a correct result upon inheritence. Patch by Bar Harel.bpo-35182: Fixed
Popen.communicate()
subsequent call crash when the child process has already closed any piped standard stream, but still continues to be running. Patch by Andriy Maletsky.bpo-38473: Use signature from inner mock for autospecced methods attached with
unittest.mock.attach_mock()
. Patch by Karthikeyan Singaravelan.bpo-38293: Add
copy.copy()
andcopy.deepcopy()
support toproperty()
objects.
Documentation¶
bpo-39153: Clarify refcounting semantics for the following functions: - PyObject_SetItem - PyMapping_SetItemString - PyDict_SetItem - PyDict_SetItemString
bpo-39392: Explain that when filling with turtle, overlap regions may be left unfilled.
bpo-39381: Mention in docs that
asyncio.get_event_loop()
implicitly creates new event loop only if called from the main thread.bpo-38918: Add an entry for
__module__
in the “function” & “method” sections of the inspect docs types and members tablebpo-3530: In the
ast
module documentation, fix a misleadingNodeTransformer
example and add advice on when to use thefix_missing_locations
function.
Tests¶
bpo-39502: Skip test_zipfile.test_add_file_after_2107() if
time.localtime()
fails withOverflowError
. It is the case on AIX 6.1 for example.bpo-38546: Fix test_ressources_gced_in_workers() of test_concurrent_futures: explicitly stop the manager to prevent leaking a child process running in the background after the test completes.
Build¶
bpo-39144: The ctags and etags build targets both include Modules/_ctypes and Python standard library source files.
Windows¶
bpo-39439: Honor the Python path when a virtualenv is active on Windows.
bpo-39393: Improve the error message when attempting to load a DLL with unresolved dependencies.
bpo-38883:
home()
andexpanduser()
on Windows now preferUSERPROFILE
and no longer useHOME
, which is not normally set for regular user accounts. This makes them again behave likeos.path.expanduser()
, which was changed to ignoreHOME
in 3.8, see bpo-36264.bpo-39185: The build.bat script has additional options for very-quiet output (-q) and very-verbose output (-vv)
IDLE¶
bpo-30780: Add remaining configdialog tests for buttons and highlights and keys tabs.
bpo-39388: IDLE Settings Cancel button now cancels pending changes
bpo-39050: Make IDLE Settings dialog Help button work again.
bpo-34118: Tag memoryview, range, and tuple as classes, the same as list, etcetera, in the library manual built-in functions list.
bpo-38792: Close an IDLE shell calltip if a
KeyboardInterrupt
or shell restart occurs. Patch by Zackery Spytz.bpo-32989: Add tests for editor newline_and_indent_event method. Remove dead code from pyparse find_good_parse_start method.
Python 3.8.1 final¶
Release date: 2019-12-18
Core and Builtins¶
bpo-39080: Fix the value of end_col_offset for Starred Expression AST nodes when they are among the elements in the args attribute of Call AST nodes.
bpo-39031: When parsing an “elif” node, lineno and col_offset of the node now point to the “elif” keyword and not to its condition, making it consistent with the “if” node. Patch by Lysandros Nikolaou.
bpo-39008:
PySys_Audit()
now requiresPy_ssize_t
to be used for size arguments in the format string, regardless of whetherPY_SSIZE_T_CLEAN
was defined at include time.
Library¶
bpo-39022: Update importlib.metadata to include improvements from importlib_metadata 1.3 including better serialization of EntryPoints and improved documentation for custom finders.
bpo-38811: Fix an unhandled exception in
pathlib
whenos.link()
is missing. Patch by Toke Høiland-Jørgensen.bpo-36406: Handle namespace packages in
doctest
. Patch by Karthikeyan Singaravelan.
Tests¶
bpo-38546: Multiprocessing and concurrent.futures tests now stop the resource tracker process when tests complete.
Windows¶
macOS¶
bpo-38295: Prevent failure of test_relative_path in test_py_compile on macOS Catalina.
IDLE¶
Python 3.8.1 release candidate 1¶
Release date: 2019-12-09
Security¶
bpo-38945: Newline characters have been escaped when performing uu encoding to prevent them from overflowing into to content section of the encoded file. This prevents malicious or accidental modification of data during the decoding process.
bpo-37228: Due to significant security concerns, the reuse_address parameter of
asyncio.loop.create_datagram_endpoint()
is no longer supported. This is because of the behavior ofSO_REUSEADDR
in UDP. For more details, see the documentation forloop.create_datagram_endpoint()
. (Contributed by Kyle Stanley, Antoine Pitrou, and Yury Selivanov in bpo-37228.)bpo-38722:
runpy
now usesio.open_code()
to open code files. Patch by Jason Killen.bpo-38804: Fixes a ReDoS vulnerability in
http.cookiejar
. Patch by Ben Caller.bpo-38622: Add additional audit events for the
ctypes
module.bpo-38418: Fixes audit event for
os.system()
to be namedos.system
.
Core and Builtins¶
bpo-38673: In REPL mode, don’t switch to PS2 if the line starts with comment or whitespace. Based on work by Batuhan Taşkaya.
bpo-38922: Calling
replace
on a code object now raises thecode.__new__
audit event.bpo-38920: Add audit hooks for when
sys.excepthook()
andsys.unraisablehook()
are invokedbpo-38892: Improve documentation for audit events table and functions.
bpo-38707:
MainThread.native_id
is now correctly reset in child processes spawned usingmultiprocessing.Process
, instead of retaining the parent’s value.bpo-38640: Fixed a bug in the compiler that was causing to raise in the presence of break statements and continue statements inside always false while loops. Patch by Pablo Galindo.
bpo-38535: Fixed line numbers and column offsets for AST nodes for calls without arguments in decorators.
bpo-38525: Fix a segmentation fault when using reverse iterators of empty
dict
objects. Patch by Dong-hee Na and Inada Naoki.bpo-35409: Ignore GeneratorExit exceptions when throwing an exception into the aclose coroutine of an asynchronous generator.
Library¶
bpo-39006: Fix asyncio when the ssl module is missing: only check for ssl.SSLSocket instance if the ssl module is available.
bpo-38708: Fix a potential IndexError in email parser when parsing an empty msg-id.
bpo-38698: Add a new
InvalidMessageID
token to email parser to represent invalid Message-ID headers. Also, add defects when there is remaining value after parsing the header.bpo-38979: Return class from
ContextVar.__class_getitem__
to simplify subclassing.bpo-38986: Make repr of C accelerated TaskWakeupMethWrapper the same as of pure Python version.
bpo-38529: Drop too noisy asyncio warning about deletion of a stream without explicit
.close()
call.bpo-38634: The
readline
module now detects if Python is linked to libedit at runtime on all platforms. Previously, the check was only done on macOS.bpo-33684: Fix
json.tool
failed to read a JSON file with non-ASCII characters when locale encoding is not UTF-8.bpo-38698: Prevent UnboundLocalError to pop up in parse_message_id
parse_message_id() was improperly using a token defined inside an exception handler, which was raising
UnboundLocalError
on parsing an invalid value. Patch by Claudiu Popa.bpo-26730: Fix
SpooledTemporaryFile.rollover()
might corrupt the file when it is in text mode. Patch by Serhiy Storchaka.bpo-38668: Calling func:
shutil.copytree
to copy a directory tree from one directory to another subdirectory resulted in an endless loop and a RecursionError. A fix was added to consume an iterator and create the list of the entries to be copied, avoiding the recursion for newly created directories. Patch by Bruno P. Kinoshita.bpo-37838:
typing.get_type_hints()
properly handles functions decorated withfunctools.wraps()
.bpo-38859: AsyncMock now returns StopAsyncIteration on the exaustion of a side_effects iterable. Since PEP-479 its Impossible to raise a StopIteration exception from a coroutine.
bpo-38857: AsyncMock fix for return values that are awaitable types. This also covers side_effect iterable values that happend to be awaitable, and wraps callables that return an awaitable type. Before these awaitables were being awaited instead of being returned as is.
bpo-38821: Fix unhandled exceptions in
argparse
when internationalizing error messages for arguments withnargs
set to special (non-integer) values. Patch by Federico Bond.bpo-38820: Make Python compatible with OpenSSL 3.0.0.
ssl.SSLSocket.getpeercert()
no longer returns IPv6 addresses with a trailing new line.bpo-38807: Update
TypeError
messages foros.path.join()
to includeos.PathLike
objects as acceptable input types.bpo-38785: Prevent asyncio from crashing if parent
__init__
is not called from a constructor of object derived fromasyncio.Future
.bpo-38723:
pdb
now usesio.open_code()
to trigger auditing events.bpo-27805: Allow opening pipes and other non-seekable files in append mode with
open()
.bpo-38686: Added support for multiple
qop
values inurllib.request.AbstractDigestAuthHandler
.bpo-38334: Fixed seeking backward on an encrypted
zipfile.ZipExtFile
.bpo-34679: asynci.ProactorEventLoop.close() now only calls signal.set_wakeup_fd() in the main thread.
bpo-31202: The case the result of
pathlib.WindowsPath.glob()
matches now the case of the pattern for literal parts.bpo-38521: Fixed erroneous equality comparison in statistics.NormalDist().
bpo-38478: Fixed a bug in
inspect.signature.bind()
that was causing it to fail when handling a keyword argument with same name as positional-only parameter. Patch by Pablo Galindo.bpo-33604: Fixed
hmac.new
andhmac.HMAC
to raise TypeError instead of ValueError when the digestmod parameter, now required in 3.8, is omitted. Also clarified the hmac module documentation and docstrings.bpo-38422: Clarify docstrings of pathlib suffix(es)
bpo-36993: Improve error reporting for corrupt zip files with bad zip64 extra data. Patch by Daniel Hillier.
bpo-36820: Break cycle generated when saving an exception in socket.py, codeop.py and dyld.py as they keep alive not only the exception but user objects through the
__traceback__
attribute. Patch by Mario Corchero.bpo-34776: Fix dataclasses to support forward references in type annotations
bpo-33348: lib2to3 now recognizes expressions after
*
and**
like inf(*[] or [])
.bpo-27657: Fix urllib.parse.urlparse() with numeric paths. A string like “path:80” is no longer parsed as a path but as a scheme (“path”) and a path (“80”).
Documentation¶
bpo-38816: Provides more details about the interaction between
fork()
and CPython’s runtime, focusing just on the C-API. This includes cautions about wherefork()
should and shouldn’t be called.bpo-38351: Modernize
email
examples from %-formatting to f-strings.bpo-38778: Document the fact that
RuntimeError
is raised ifos.fork()
is called in a subinterpreter.bpo-38592: Add Brazilian Portuguese to the language switcher at Python Documentation website.
Tests¶
bpo-38547: Fix test_pty: if the process is the session leader, closing the master file descriptor raises a SIGHUP signal: simply ignore SIGHUP when running the tests.
bpo-38992: Fix a test for
math.fsum()
that was failing due to constant folding.bpo-38965: Fix test_faulthandler on GCC 10. Use the “volatile” keyword in
faulthandler._stack_overflow()
to prevent tail call optimization on any compiler, rather than relying on compiler specific pragma.bpo-38875: test_capi: trashcan tests now require the test “cpu” resource.
bpo-38841: Skip asyncio test_create_datagram_endpoint_existing_sock_unix on platforms lacking a functional bind() for named unix domain sockets.
bpo-38669: Raise
TypeError
when passing target as a string withunittest.mock.patch.object()
.bpo-35998: Fix a race condition in test_asyncio.test_start_tls_server_1(). Previously, there was a race condition between the test main() function which replaces the protocol and the test ServerProto protocol which sends ANSWER once it gets HELLO. Now, only the test main() function is responsible to send data, ServerProto no longer sends data.
Build¶
bpo-37404:
asyncio
now raisesTyperError
when calling incompatible methods with anssl.SSLSocket
socket. Patch by Ido Michael.bpo-38809: On Windows, build scripts will now recognize and use python.exe from an active virtual env.
bpo-38684: Fix _hashlib build when Blake2 is disabled, but OpenSSL supports it.
bpo-37415: Fix stdatomic.h header check for ICC compiler: the ICC implementation lacks atomic_uintptr_t type which is needed by Python.
Windows¶
bpo-33125: Add support for building and releasing Windows ARM64 packages.
bpo-38589: Fixes HTML Help shortcut when Windows is not installed to C drive
bpo-38453: Ensure ntpath.realpath() correctly resolves relative paths.
bpo-38519: Restores the internal C headers that were missing from the nuget.org and Microsoft Store packages.
bpo-38492: Remove
pythonw.exe
dependency on the Microsoft C++ runtime.
macOS¶
bpo-37931: Fixed a crash on OSX dynamic builds that occurred when re-initializing the posix module after a Py_Finalize if the environment had changed since the previous
import posix
. Patch by Benoît Hudson.
IDLE¶
bpo-38862: ‘Strip Trailing Whitespace’ on the Format menu removes extra newlines at the end of non-shell files.
bpo-26353: Stop adding newline when saving an IDLE shell window.
bpo-38636: Fix IDLE Format menu tab toggle and file indent width. These functions (default shortcuts Alt-T and Alt-U) were mistakenly disabled in 3.7.5 and 3.8.0.
bpo-4630: Add an option to toggle IDLE’s cursor blink for shell, editor, and output windows. See Settings, General, Window Preferences, Cursor Blink. Patch by Zackery Spytz.
bpo-38598: Do not try to compile IDLE shell or output windows
C API¶
bpo-37633: Re-export some function compatibility wrappers for macros in
pythonrun.h
.bpo-38540: Fixed possible leak in
PyArg_Parse()
and similar functions for format units"es#"
and"et#"
when the macroPY_SSIZE_T_CLEAN
is not defined.bpo-36389: The
_PyObject_CheckConsistency()
function is now also available in release mode. For example, it can be used to debug a crash in thevisit_decref()
function of the GC.
Python 3.8.0 final¶
Release date: 2019-10-14
Core and Builtins¶
bpo-38469: Fixed a bug where the scope of named expressions was not being resolved correctly in the presence of the global keyword. Patch by Pablo Galindo.
bpo-38379: When cyclic garbage collection (gc) runs finalizers that resurrect unreachable objects, the current gc run ends, without collecting any cyclic trash. However, the statistics reported by
collect()
andget_stats()
claimed that all cyclic trash found was collected, and that the resurrected objects were collected. Changed the stats to report that none were collected.
Library¶
bpo-38449: Revert PR 15522, which introduces a regression in
mimetypes.guess_type()
due to improper handling of filenames as urls.bpo-38431: Fix
__repr__
method fordataclasses.InitVar
to support typing objects, patch by Samuel Colvin.bpo-38109: Add missing
stat.S_IFDOOR
,stat.S_IFPORT
,stat.S_IFWHT
,stat.S_ISDOOR()
,stat.S_ISPORT()
, andstat.S_ISWHT()
values to the Python implementation ofstat
.bpo-38405: Nested subclasses of
typing.NamedTuple
are now pickleable.bpo-38332: Prevent
KeyError
thrown by_encoded_words.decode()
when given an encoded-word with invalid content-type encoding from propagating all the way toemail.message.get()
.bpo-38341: Add
smtplib.SMTPNotSupportedError
to thesmtplib
exported names.bpo-13153: OS native encoding is now used for converting between Python strings and Tcl objects. This allows to display, copy and paste to clipboard emoji and other non-BMP characters. Converting strings from Tcl to Python and back now never fails (except MemoryError).
Documentation¶
bpo-38294: Add list of no-longer-escaped chars to re.escape documentation.
Tests¶
bpo-37531: On timeout, regrtest no longer attempts to call
popen.communicate()
again: it can hang until all child processes using stdout and stderr pipes completes. Kill the worker process and ignores its output. Change also the faulthandler timeout of the main process from 1 minute to 5 minutes, for Python slowest buildbots.
Windows¶
IDLE¶
bpo-36698: IDLE no longer fails when write non-encodable characters to stderr. It now escapes them with a backslash, as the regular Python interpreter. Added the
errors
field to the standard streams.
Tools/Demos¶
bpo-38118: Update Valgrind suppression file to ignore a false alarm in
PyUnicode_Decode()
when using GCC builtin strcmp().bpo-38347: pathfix.py: Assume all files that end on ‘.py’ are Python scripts when working recursively.
C API¶
bpo-38395: Fix a crash in
weakref.proxy
objects due to incorrect lifetime management when calling some associated methods that may delete the last reference to object being referenced by the proxy. Patch by Pablo Galindo.
Python 3.8.0 release candidate 1¶
Release date: 2019-10-01
Security¶
bpo-38243: Escape the server title of
xmlrpc.server.DocXMLRPCServer
when rendering the document page as HTML. (Contributed by Dong-hee Na in bpo-38243.)bpo-38174: Update vendorized expat library version to 2.2.8, which resolves CVE-2019-15903.
bpo-37764: Fixes email._header_value_parser.get_unstructured going into an infinite loop for a specific case in which the email header does not have trailing whitespace, and the case in which it contains an invalid encoded word. Patch by Ashwin Ramaswami.
Core and Builtins¶
bpo-38006: Fix a bug due to the interaction of weakrefs and the cyclic garbage collector. We must clear any weakrefs in garbage in order to prevent their callbacks from executing and causing a crash.
bpo-38317: Fix warnings options priority:
PyConfig.warnoptions
has the highest priority, as stated in the PEP 587.bpo-36871: Improve error handling for the assert_has_calls and assert_has_awaits methods of mocks. Fixed a bug where any errors encountered while binding the expected calls to the mock’s spec were silently swallowed, leading to misleading error output.
bpo-38236: Python now dumps path configuration if it fails to import the Python codecs of the filesystem and stdio encodings.
bpo-38013: Allow to call
async_generator_athrow().throw(...)
even for non-started async generator helper. It fixes annoying warning at the end ofasyncio.run()
call.bpo-38124: Fix an off-by-one error in PyState_AddModule that could cause out-of-bounds memory access.
bpo-38005: Fixed comparing and creating of InterpreterID and ChannelID.
bpo-37994: Fixed silencing arbitrary errors if an attribute lookup fails in several sites. Only AttributeError should be silenced.
bpo-37990: Fix elapsed time in gc stats was not printed correctly. This bug was a regression in 3.8b4.
bpo-37966: The implementation of
is_normalized()
has been greatly sped up on strings that aren’t normalized, by implementing the full normalization-quick-check algorithm from the Unicode standard.bpo-20490: Improve import error message for partially initialized module on circular
from
imports - by Anthony Sottile.bpo-37409: Ensure explicit relative imports from interactive sessions and scripts (having no parent package) always raise ImportError, rather than treating the current module as the package. Patch by Ben Lewis.
bpo-37619: When adding a wrapper descriptor from one class to a different class (for example, setting
__add__ = str.__add__
on anint
subclass), an exception is correctly raised when the operator is called.bpo-30773: Prohibit parallel running of aclose() / asend() / athrow(). Fix ag_running to reflect the actual running status of the AG.
Library¶
bpo-38319: sendfile() used in socket and shutil modules was raising OverflowError for files >= 2GiB on 32-bit architectures. (patch by Giampaolo Rodola)
bpo-38242: Revert the new asyncio Streams API
bpo-38019: Correctly handle pause/resume reading of closed asyncio unix pipe.
bpo-38163: Child mocks will now detect their type as either synchronous or asynchronous, asynchronous child mocks will be AsyncMocks and synchronous child mocks will be either MagicMock or Mock (depending on their parent type).
bpo-38161: Removes _AwaitEvent from AsyncMock.
bpo-38216: Allow the rare code that wants to send invalid http requests from the
http.client
library a way to do so. The fixes for bpo-30458 led to breakage for some projects that were relying on this ability to test their own behavior in the face of bad requests.bpo-38108: Any synchronous magic methods on an AsyncMock now return a MagicMock. Any asynchronous magic methods on a MagicMock now return an AsyncMock.
bpo-38248: asyncio: Fix inconsistent immediate Task cancellation
bpo-38237: The arguments for the builtin pow function are more descriptive. They can now also be passed in as keywords.
bpo-38191: Constructors of
NamedTuple
andTypedDict
types now accept arbitrary keyword argument names, including “cls”, “self”, “typename”, “_typename”, “fields” and “_fields”. Passing positional arguments by keyword is deprecated.bpo-38185: Fixed case-insensitive string comparison in
sqlite3.Row
indexing.bpo-38136: Changes AsyncMock call count and await count to be two different counters. Now await count only counts when a coroutine has been awaited, not when it has been called, and vice-versa. Update the documentation around this.
bpo-37828: Fix default mock name in
unittest.mock.Mock.assert_called()
exceptions. Patch by Abraham Toriz Cruz.bpo-38175: Fix a memory leak in comparison of
sqlite3.Row
objects.bpo-33936: _hashlib no longer calls obsolete OpenSSL initialization function with OpenSSL 1.1.0+.
bpo-34706: Preserve subclassing in inspect.Signature.from_callable.
bpo-38153: Names of hashing algorithms frome OpenSSL are now normalized to follow Python’s naming conventions. For example OpenSSL uses sha3-512 instead of sha3_512 or blake2b512 instead of blake2b.
bpo-38115: Fix a bug in dis.findlinestarts() where it would return invalid bytecode offsets. Document that a code object’s co_lnotab can contain invalid bytecode offsets.
bpo-38148: Add slots to
asyncio
transport classes, which can reduce memory usage.bpo-36991: Fixes a potential incorrect AttributeError exception escaping ZipFile.extract() in some unsupported input error situations.
bpo-38134: Remove obsolete copy of PBKDF2_HMAC_fast. All supported OpenSSL versions contain a fast implementation.
bpo-38132: The OpenSSL hashlib wrapper uses a simpler implementation. Several Macros and pointless caches are gone. The hash name now comes from OpenSSL’s EVP. The algorithm name stays the same, except it is now always lower case.
bpo-38008: Fix parent class check in protocols to correctly identify the module that provides a builtin protocol, instead of assuming they all come from the
collections.abc
modulebpo-37405: Fixed regression bug for socket.getsockname() for non-CAN_ISOTP AF_CAN address family sockets by returning a 1-tuple instead of string.
bpo-38121: Update parameter names on functions in importlib.metadata matching the changes in the 0.22 release of importlib_metadata.
bpo-38110: The os.closewalk() implementation now uses the libc fdwalk() API on platforms where it is available.
bpo-38093: Fixes AsyncMock so it doesn’t crash when used with AsyncContextManagers or AsyncIterators.
bpo-37488: Add warning to
datetime.utctimetuple()
,datetime.utcnow()
anddatetime.utcfromtimestamp()
.bpo-38086: Update importlib.metadata with changes from importlib_metadata 0.21.
bpo-37251: Remove
__code__
check in AsyncMock that incorrectly evaluated function specs as async objects but failed to evaluate classes with__await__
but no__code__
attribute defined as async objects.bpo-38066: Hide internal asyncio.Stream methods: feed_eof(), feed_data(), set_exception() and set_transport().
bpo-38059: inspect.py now uses sys.exit() instead of exit()
bpo-37953: In
typing
, improved the__hash__
and__eq__
methods forForwardReferences
.bpo-38026: Fixed
inspect.getattr_static()
usedisinstance
while it should avoid dynamic lookup.bpo-38010: In
importlib.metadata
sync withimportlib_metadata
0.20, clarifying behavior offiles()
and fixing issue where only one requirement was returned forrequires()
ondist-info
packages.bpo-38006: weakref.WeakValueDictionary defines a local remove() function used as callback for weak references. This function was created with a closure. Modify the implementation to avoid the closure.
bpo-34410: Fixed a crash in the
tee()
iterator when re-enter it. RuntimeError is now raised in this case.bpo-37140: Fix a ctypes regression of Python 3.8. When a ctypes.Structure is passed by copy to a function, ctypes internals created a temporary object which had the side effect of calling the structure finalizer (__del__) twice. The Python semantics requires a finalizer to be called exactly once. Fix ctypes internals to no longer call the finalizer twice.
bpo-37972: Subscripts to the
unittest.mock.call
objects now receive the same chaining mechanism as any other custom attributes, so that the following usage no longer raises aTypeError
:call().foo().__getitem__(‘bar’)
Patch by blhsing
bpo-22347: Update mimetypes.guess_type to allow proper parsing of URLs with only a host name. Patch by Dong-hee Na.
bpo-37885: venv: Don’t generate unset variable warning on deactivate.
bpo-37424: Fixes a possible hang when using a timeout on
subprocess.run()
while capturing output. If the child process spawned its own children or otherwise connected its stdout or stderr handles with another process, we could hang after the timeout was reached and our child was killed when attempting to read final output from the pipes.bpo-37212:
unittest.mock.call()
now preserves the order of keyword arguments in repr output. Patch by Karthikeyan Singaravelan.bpo-37305: Add .webmanifest -> application/manifest+json to list of recognized file types and content type headers
bpo-21872: Fix
lzma
: module decompresses data incompletely. When decompressing a FORMAT_ALONE format file, and it doesn’t have the end marker, sometimes the last one to dozens bytes can’t be output. Patch by Ma Lin.bpo-37206: Default values which cannot be represented as Python objects no longer improperly represented as
None
in function signatures.bpo-12144: Ensure cookies with
expires
attribute are handled inCookieJar.make_cookies()
.bpo-31163: pathlib.Path instance’s rename and replace methods now return the new Path instance.
bpo-25068:
urllib.request.ProxyHandler
now lowercases the keys of the passed dictionary.bpo-21315: Email headers containing RFC2047 encoded words are parsed despite the missing whitespace, and a defect registered. Also missing trailing whitespace after encoded words is now registered as a defect.
bpo-36250: Ignore
ValueError
fromsignal
withinteraction
in non-main thread.bpo-35168:
shlex.shlex.punctuation_chars
is now a read-only property.bpo-20504: Fixes a bug in
cgi
module when a multipart/form-data request has noContent-Length
header.bpo-34519: Add additional aliases for HP Roman 8. Patch by Michael Osipov.
Documentation¶
bpo-26868: Fix example usage of
PyModule_AddObject()
to properly handle errors.bpo-36797: Fix a dead link in the distutils API Reference.
bpo-37977: Warn more strongly and clearly about pickle insecurity
bpo-37937: Mention
frame.f_trace
insys.settrace()
docs.bpo-36260: Add decompression pitfalls to zipfile module documentation.
bpo-36960: Restructured the
datetime
docs in the interest of making them more user-friendly and improving readability. Patch by Brad Solomon.bpo-23460: The documentation for decimal string formatting using the
:g
specifier has been updated to reflect the correct exponential notation cutoff point. Original patch contributed by Tuomas Suutari.bpo-35803: Document and test that
tempfile
functions may accept a path-like object for thedir
argument. Patch by Anthony Sottile.bpo-33944: Added a note about the intended use of code in .pth files.
bpo-34293: Fix the Doc/Makefile regarding PAPER environment variable and PDF builds
Tests¶
bpo-38239: Fix test_gdb for Link Time Optimization (LTO) builds.
bpo-38275: test_ssl now handles disabled TLS/SSL versions better. OpenSSL’s crypto policy and run-time settings are recognized and tests for disabled versions are skipped. Tests also accept more TLS minimum_versions for platforms that override OpenSSL’s default with strict settings.
bpo-38271: The private keys for test_ssl were encrypted with 3DES in traditional PKCS#5 format. 3DES and the digest algorithm of PKCS#5 are blocked by some strict crypto policies. Use PKCS#8 format with AES256 encryption instead.
bpo-38270: test.support now has a helper function to check for availibility of a hash digest function. Several tests are refactored avoid MD5 and use SHA256 instead. Other tests are marked to use MD5 and skipped when MD5 is disabled.
bpo-37123: Multiprocessing test test_mymanager() now also expects -SIGTERM, not only exitcode 0. BaseManager._finalize_manager() sends SIGTERM to the manager process if it takes longer than 1 second to stop, which happens on slow buildbots.
bpo-38212: Multiprocessing tests: increase test_queue_feeder_donot_stop_onexc() timeout from 1 to 60 seconds.
bpo-38117: Test with OpenSSL 1.1.1d
bpo-37531: Enhance regrtest multiprocess timeout: write a message when killing a worker process, catch popen.kill() and popen.wait() exceptions, put a timeout on the second call to popen.communicate().
bpo-37876: Add tests for ROT-13 codec.
bpo-37252: Fix assertions in
test_close
andtest_events_mask_overflow
devpoll tests.bpo-34001: Make test_ssl pass with LibreSSL. LibreSSL handles minimum and maximum TLS version differently than OpenSSL.
bpo-36919: Make
test_source_encoding.test_issue2301
implementation independent. The test will work now for both CPython and IronPython.bpo-34596: Fallback to a default reason when
unittest.skip()
is uncalled. Patch by Naitree Zhu.
Build¶
bpo-38301: In Solaris family, we must be sure to use
-D_REENTRANT
. Patch by Jesús Cea Avión.bpo-36210: Update optional extension module detection for AIX. ossaudiodev and spwd are not applicable for AIX, and are no longer reported as missing. 3rd-party packaging of ncurses (with ASIS support) conflicts with officially supported AIX curses library, so configure AIX to use libcurses.a. However, skip trying to build _curses_panel.
patch by M Felt
bpo-36002: Locate
llvm-profdata
andllvm-ar
binaries usingAC_PATH_TOOL
rather thanAC_PATH_TARGET_TOOL
.bpo-37936: The
.gitignore
file systematically keeps “rooted”, with a non-trailing slash, all the rules that are meant to apply to files in a specific place in the repo. Previously, when the intended file to ignore happened to be at the root of the repo, we’d most often accidentally also ignore files and directories with the same name anywhere in the tree.bpo-37936: The
.gitignore
file no longer applies to any files that are in fact tracked in the Git repository. Patch by Greg Price.
Windows¶
bpo-38117: Update bundled OpenSSL to 1.1.1d
bpo-38092: Reduce overhead when using multiprocessing in a Windows virtual environment.
bpo-38133: Allow py.exe launcher to locate installations from the Microsoft Store and improve display of active virtual environments.
bpo-38114: The
pip.ini
is no longer included in the Nuget package.bpo-36634:
os.cpu_count()
now returns active processors rather than maximum processors.bpo-36634: venv activate.bat now works when the existing variables contain double quote characters.
bpo-38081: Prevent error calling
os.path.realpath()
on'NUL'
.bpo-38087: Fix case sensitivity in test_pathlib and test_ntpath.
bpo-38088: Fixes distutils not finding vcruntime140.dll with only the v142 toolset installed.
bpo-37283: Ensure command-line and unattend.xml setting override previously detected states in Windows installer.
bpo-38030: Fixes
os.stat()
failing for block devices on Windowsbpo-38020: Fixes potential crash when calling
os.readlink()
(or indirectly throughrealpath()
) on a file that is not a supported link.bpo-37705: Improve the implementation of
winerror_to_errno()
.bpo-37702: Fix memory leak on Windows in creating an SSLContext object or running urllib.request.urlopen(’https://…’).
bpo-37445: Include the
FORMAT_MESSAGE_IGNORE_INSERTS
flag inFormatMessageW()
calls.bpo-37380: Don’t collect unfinished processes with
subprocess._active
on Windows to cleanup later. Patch by Ruslan Kuprieiev.bpo-32587: Make
winreg.REG_MULTI_SZ
support zero-length strings.
macOS¶
IDLE¶
bpo-35379: When exiting IDLE, catch any AttributeError. One happens when EditorWindow.close is called twice. Printing a traceback, when IDLE is run from a terminal, is useless and annoying.
bpo-38183: To avoid problems, test_idle ignores the user config directory. It no longer tries to create or access .idlerc or any files within. Users must run IDLE to discover problems with saving settings.
bpo-38077: IDLE no longer adds ‘argv’ to the user namespace when initializing it. This bug only affected 3.7.4 and 3.8.0b2 to 3.8.0b4.
bpo-38041: Shell restart lines now fill the window width, always start with ‘=’, and avoid wrapping unnecessarily. The line will still wrap if the included file name is long relative to the width.
bpo-35771: To avoid occasional spurious test_idle failures on slower machines, increase the
hover_delay
in test_tooltip.bpo-37902: Add mousewheel scrolling for IDLE module, path, and stack browsers. Patch by George Zhang.
Tools/Demos¶
C API¶
bpo-38234:
Py_SetPath()
now setssys.executable
to the program full path (Py_GetProgramFullPath()
) rather than to the program name (Py_GetProgramName()
).bpo-38234: Python ignored arguments passed to
Py_SetPath()
,Py_SetPythonHome()
andPy_SetProgramName()
: fix Python initialization to use specified arguments.bpo-38205: The
Py_UNREACHABLE()
macro now callsPy_FatalError()
.bpo-37879: Fix subtype_dealloc to suppress the type decref when the base type is a C heap type
Python 3.8.0 beta 4¶
Release date: 2019-08-29
Security¶
bpo-34155: Fix parsing of invalid email addresses with more than one
@
(e.g. a@b@c.com.) to not return the part before 2nd@
as valid email address. Patch by maxking & jpic.
Core and Builtins¶
bpo-37947: Adjust correctly the recursion level in the symtable generation for named expressions. Patch by Pablo Galindo.
bpo-37830: Fixed compilation of
break
andcontinue
in thefinally
block when the correspondingtry
block containsreturn
with a non-constant value.bpo-32912: Reverted bpo-32912: emitting
SyntaxWarning
instead ofDeprecationWarning
for invalid escape sequences in string and bytes literals.bpo-37757: PEP 572: As described in the PEP, assignment expressions now raise
SyntaxError
when their interaction with comprehension scoping results in an ambiguous target scope.The
TargetScopeError
subclass originally proposed by the PEP has been removed in favour of just raising regular syntax errors for the disallowed cases.bpo-36311: Decoding bytes objects larger than 2GiB is faster and no longer fails when a multibyte characters spans a chunk boundary.
bpo-37433: Fix
SyntaxError
indicator printing too many spaces for multi-line strings - by Anthony Sottile.bpo-20523:
pdb.Pdb
supports ~/.pdbrc in Windows 7. Patch by Tim Hopper and Dan Lidral-Porter.
Library¶
bpo-37834: Prevent shutil.rmtree exception when built on non-Windows system without fd system call support, like older versions of macOS.
bpo-37965: Fix C compiler warning caused by distutils.ccompiler.CCompiler.has_function.
bpo-37960:
repr()
of buffered and text streams now silences only expected exceptions when get the value of “name” and “mode” attributes.bpo-37951: Most features of the subprocess module now work again in subinterpreters. Only preexec_fn is restricted in subinterpreters.
bpo-36205: Fix the rusage implementation of time.process_time() to correctly report the sum of the system and user CPU time.
bpo-37950: Fix
ast.dump()
when call with incompletely initialized node.bpo-34679: Restores instantiation of Windows IOCP event loops from the non-main thread.
bpo-36917: Add default implementation of the
ast.NodeVisitor.visit_Constant()
method which emits a deprecation warning and calls corresponding methodyvisit_Num()
,visit_Str()
, etc.bpo-37798: Update test_statistics.py to verify that the statistics module works well for both C and Python implementations. Patch by Dong-hee Na
bpo-26589: Added a new status code to the http module: 451 UNAVAILABLE_FOR_LEGAL_REASONS
bpo-37915: Fix a segmentation fault that appeared when comparing instances of
datetime.timezone
anddatetime.tzinfo
objects. Patch by Pablo Galindo.bpo-37868: Fix dataclasses.is_dataclass when given an instance that never raises AttributeError in __getattr__. That is, an object that returns something for __dataclass_fields__ even if it’s not a dataclass.
bpo-37811: Fix
socket
module’ssocket.connect(address)
function being unable to establish connection in case of interrupted system call. The problem was observed on all OSes whichpoll(2)
system call can take only non-negative integers and -1 as a timeout value.bpo-21131: Fix
faulthandler.register(chain=True)
stack. faulthandler now allocates a dedicated stack ofSIGSTKSZ*2
bytes, instead of justSIGSTKSZ
bytes. Calling the previous signal handler in faulthandler signal handler uses more thanSIGSTKSZ
bytes of stack memory on some platforms.bpo-37798: Add C fastpath for statistics.NormalDist.inv_cdf() Patch by Dong-hee Na
bpo-37819: Add Fraction.as_integer_ratio() to match the corresponding methods in bool, int, float, and decimal.
bpo-37810: Fix
difflib
?
hint in diff output when dealing with tabs. Patch by Anthony Sottile.bpo-37772: In
zipfile.Path
, when adding implicit dirs, ensure that ancestral directories are added and that duplicates are excluded.bpo-28292: Mark calendar.py helper functions as being private. The follows PEP 8 guidance to maintain the style conventions in the module and it addresses a known case of user confusion.
bpo-18049: Add definition of THREAD_STACK_SIZE for AIX in Python/thread_pthread.h The default thread stacksize caused crashes with the default recursion limit Patch by M Felt
bpo-37738: Fix the implementation of curses
addch(str, color_pair)
: pass the color pair tosetcchar()
, instead of always passing 0 as the color pair.bpo-37723: Fix performance regression on regular expression parsing with huge character sets. Patch by Yann Vaginay.
bpo-32178: Fix IndexError in
email
package when trying to parse invalid address fields starting with:
.bpo-37685: Fixed comparisons of
datetime.timedelta
anddatetime.timezone
.bpo-37695: Correct
curses.unget_wch()
error message. Patch by Anthony Sottile.bpo-37354: Make Activate.ps1 Powershell script static to allow for signing it.
bpo-37664: Update wheels bundled with ensurepip (pip 19.2.3 and setuptools 41.2.0)
bpo-37642: Allowed the pure Python implementation of
datetime.timezone
to represent sub-minute offsets close to minimum and maximum boundaries, specifically in the ranges (23:59, 24:00) and (-23:59, 24:00). Patch by Ngalim Siregarbpo-16970: Adding a value error when an invalid value in passed to nargs Patch by Robert Leenders
bpo-37587: Make json.loads faster for long strings. (Patch by Marco Paolini)
bpo-18378: Recognize “UTF-8” as a valid value for LC_CTYPE in locale._parse_localename.
bpo-37531: “python3 -m test -jN –timeout=TIMEOUT” now kills a worker process if it runs longer than TIMEOUT seconds.
bpo-37482: Fix serialization of display name in originator or destination address fields with both encoded words and special chars.
bpo-37372: Fix error unpickling datetime.time objects from Python 2 with seconds>=24. Patch by Justin Blanchard.
bpo-37085: Add the optional Linux SocketCAN Broadcast Manager constants, used as flags to configure the BCM behaviour, in the socket module. Patch by Karl Ding.
bpo-36871: Ensure method signature is used instead of constructor signature of a class while asserting mock object against method calls. Patch by Karthikeyan Singaravelan.
bpo-36582: Fix
UserString.encode()
to correctly returnbytes
rather than aUserString
instance.bpo-34775: Division handling of PurePath now returns NotImplemented instead of raising a TypeError when passed something other than an instance of str or PurePath. Patch by Roger Aiudi.
Documentation¶
bpo-37979: Added a link to dateutil.parser.isoparse in the datetime.fromisoformat documentation. Patch by Paul Ganssle
bpo-37759: Beginning edits to Whatsnew 3.8
bpo-37726: Stop recommending getopt in the tutorial for command line argument parsing and promote argparse.
bpo-37256: Fix wording of arguments for
Request
inurllib.request
bpo-37004: In the documentation for difflib, a note was added explicitly warning that the results of SequenceMatcher’s ratio method may depend on the order of the input strings.
bpo-36487: Make C-API docs clear about what the “main” interpreter is.
Tests¶
bpo-37805: Add tests for json.dump(…, skipkeys=True). Patch by Dong-hee Na.
Build¶
bpo-37707: Mark some individual tests to skip when –pgo is used. The tests marked increase the PGO task time significantly and likely don’t help improve optimization of the final executable.
Windows¶
bpo-37549:
os.dup()
no longer fails for standard streams on Windows 7.bpo-1311: The
nul
file on Windows now returns True fromexists()
and a valid result fromos.stat()
withS_IFCHR
set.bpo-9949: Enable support for following symlinks in
os.realpath()
.bpo-37834: Treat all name surrogate reparse points on Windows in
os.lstat()
and other reparse points as regular files inos.stat()
.bpo-36266: Add the module name in the formatted error message when DLL load fail happens during module import in
_PyImport_FindSharedFuncptrWindows()
. Patch by Srinivas Nyayapati.bpo-25172: Trying to import the
crypt
module on Windows will result in anImportError
with a message explaining that the module isn’t supported on Windows. On other platforms, if the underlying_crypt
module is not available, the ImportError will include a message explaining the problem.bpo-37778: Fixes the icons used for file associations to the Microsoft Store package.
bpo-37734: Fix use of registry values to launch Python from Microsoft Store app.
bpo-28269: Replace use of
strcasecmp()
for the system function_stricmp()
. Patch by Minmin Gong.
macOS¶
bpo-18049: Increase the default stack size of threads from 5MB to 16MB on macOS, to match the stack size of the main thread. This avoids crashes on deep recursion in threads.
IDLE¶
bpo-37824: Properly handle user input warnings in IDLE shell. Cease turning SyntaxWarnings into SyntaxErrors.
bpo-37929: IDLE Settings dialog now closes properly when there is no shell window.
bpo-37849: Fixed completions list appearing too high or low when shown above the current line.
bpo-36419: Refactor IDLE autocomplete and improve testing.
bpo-37748: Reorder the Run menu. Put the most common choice, Run Module, at the top.
Tools/Demos¶
C API¶
Python 3.8.0 beta 3¶
Release date: 2019-07-29
Security¶
bpo-37461: Fix an infinite loop when parsing specially crafted email headers. Patch by Abhilash Raj.
Core and Builtins¶
Library¶
bpo-37697: Syncronize
importlib.metadata
with importlib_metadata 0.19, improving handling of EGG-INFO files and fixing a crash when entry point names contained colons.bpo-37691: Let math.dist() accept coordinates as sequences (or iterables) rather than just tuples.
bpo-37664: Update wheels bundled with ensurepip (pip 19.2.1 and setuptools 41.0.1)
bpo-36324: Make internal attributes for statistics.NormalDist() private.
bpo-37491: Fix
IndexError
when parsing email headers with unexpectedly ending bare-quoted string value. Patch by Abhilash Raj.bpo-37579: Return
NotImplemented
in Python implementation of__eq__
fortimedelta
andtime
when the other object being compared is not of the same type to match C implementation. Patch by Karthikeyan Singaravelan.bpo-21478: Record calls to parent when autospecced object is attached to a mock using
unittest.mock.attach_mock()
. Patch by Karthikeyan Singaravelan.bpo-37502: pickle.loads() no longer raises TypeError when the buffers argument is set to None
bpo-37520: Correct behavior for zipfile.Path.parent when the path object identifies a subdirectory.
bpo-18374: Fix the
.col_offset
attribute of nestedast.BinOp
instances which had a too large value in some situations.bpo-37421: Fix
multiprocessing.util.get_temp_dir()
finalizer: clear also the ‘tempdir’ configuration of the current process, so next call toget_temp_dir()
will create a new temporary directory, rather than reusing the removed temporary directory.bpo-37481: The distutils
bdist_wininst
command is deprecated in Python 3.8, usebdist_wheel
(wheel packages) instead.bpo-26967: An
ArgumentParser
withallow_abbrev=False
no longer disables grouping of short flags, such as-vv
, but only disables abbreviation of long flags as documented. Patch by Zac Hatfield-Dodds.bpo-37347:
sqlite3.Connection.create_aggregate()
,sqlite3.Connection.create_function()
,sqlite3.Connection.set_authorizer()
,sqlite3.Connection.set_progress_handler()
sqlite3.Connection.set_trace_callback()
methods lead to segfaults if some of these methods are called twice with an equal object but not the same. Now callbacks are stored more carefully. Patch by Aleksandr Balezin.bpo-36564: Fix infinite loop in email header folding logic that would be triggered when an email policy’s max_line_length is not long enough to include the required markup and any values in the message. Patch by Paul Ganssle
Documentation¶
bpo-32910: Remove implementation-specific behaviour of how venv’s Deactivate works.
bpo-37284: Add a brief note to indicate that any new
sys.implementation
required attributes must go through the PEP process.bpo-30088: Documented that
mailbox.Maildir
constructor doesn’t attempt to verify the maildir folder layout correctness. Patch by Sviatoslav Sydorenko.bpo-37521: Fix
importlib
examples to insert any newly created modules via importlib.util.module_from_spec() immediately into sys.modules instead of after calling loader.exec_module().Thanks to Benjamin Mintz for finding the bug.
bpo-37456: Slash (‘/’) is now part of syntax.
bpo-37487: Fix PyList_GetItem index description to include 0.
bpo-37149: Replace the dead link to the Tkinter 8.5 reference by John Shipman, New Mexico Tech, with a link to the archive.org copy.
bpo-37478: Added possible exceptions to the description of os.chdir().
Tests¶
bpo-37558: Fix test_shared_memory_cleaned_after_process_termination name handling
bpo-37526: Add
test.support.catch_threading_exception()
: context manager catchingthreading.Thread
exception usingthreading.excepthook()
.bpo-37421: test_concurrent_futures now explicitly stops the ForkServer instance if it’s running.
bpo-37421: multiprocessing tests now stop the ForkServer instance if it’s running: close the “alive” file descriptor to ask the server to stop and then remove its UNIX address.
Build¶
bpo-36044: Reduce the number of unit tests run for the PGO generation task. This speeds up the task by a factor of about 15x. Running the full unit test suite is slow. This change may result in a slightly less optimized build since not as many code branches will be executed. If you are willing to wait for the much slower build, the old behavior can be restored using ‘./configure [..] PROFILE_TASK=”-m test –pgo-extended”’. We make no guarantees as to which PGO task set produces a faster build. Users who care should run their own relevant benchmarks as results can depend on the environment, workload, and compiler tool chain.
Windows¶
bpo-37672: Switch Windows Store package’s pip to use bundled
pip.ini
instead ofPIP_USER
variable.
IDLE¶
bpo-37692: Improve highlight config sample with example shell interaction and better labels for shell elements.
bpo-37628: Settings dialog no longer expands with font size.
bpo-37627: Initialize the Customize Run dialog with the command line arguments most recently entered before. The user can optionally edit before submitting them.
bpo-33610: Fix code context not showing the correct context when first toggled on.
bpo-37530: Optimize code context to reduce unneeded background activity. Font and highlight changes now occur along with text changes instead of after a random delay.
bpo-27452: Cleanup
config.py
by inliningRemoveFile
and simplifying the handling offile
inCreateConfigHandlers
.bpo-17535: Add optional line numbers for IDLE editor windows. Windows open without line numbers unless set otherwise in the General tab of the configuration dialog.
bpo-26806: To compensate for stack frames added by IDLE and avoid possible problems with low recursion limits, add 30 to limits in the user code execution process. Subtract 30 when reporting recursion limits to make this addition mostly transparent.
bpo-36390: Gather Format menu functions into format.py. Combine paragraph.py, rstrip.py, and format methods from editor.py.
Tools/Demos¶
bpo-37675: 2to3 now works when run from a zipped standard library.
Python 3.8.0 beta 2¶
Release date: 2019-07-04
Security¶
bpo-37363: Adds audit events for the range of supported run commands (see Linha de comando e ambiente).
bpo-37463: ssl.match_hostname() no longer accepts IPv4 addresses with additional text after the address and only quad-dotted notation without trailing whitespaces. Some inet_aton() implementations ignore whitespace and all data after whitespace, e.g. ‘127.0.0.1 whatever’.
bpo-37363: Adds audit events for
ensurepip
,ftplib
,glob
,imaplib
,nntplib
,pdb
,poplib
,shutil
,smtplib
,sqlite3
,subprocess
,telnetlib
,tempfile
andwebbrowser
, as well asos.listdir()
,os.scandir()
andbreakpoint()
.bpo-37364:
io.open_code()
is now used when reading.pth
files.bpo-34631: Updated OpenSSL to 1.1.1c in Windows installer
Core and Builtins¶
bpo-37467: Fix
sys.excepthook()
andPyErr_Display()
if a filename is a bytes string. For example, for a SyntaxError exception where the filename attribute is a bytes string.bpo-37417:
bytearray.extend()
now correctly handles errors that arise during iteration. Patch by Brandt Bucher.bpo-24214: Improved support of the surrogatepass error handler in the UTF-8 and UTF-16 incremental decoders.
bpo-35224: Reverse evaluation order of key: value in dict comprehensions as proposed in PEP 572. I.e. in
{k: v for ...}
,k
will be evaluated beforev
.bpo-37316: Fix the
PySys_Audit()
call inmmap.mmap
.bpo-37269: Fix a bug in the peephole optimizer that was not treating correctly constant conditions with binary operators. Patch by Pablo Galindo.
bpo-37213: Handle correctly negative line offsets in the peephole optimizer. Patch by Pablo Galindo.
bpo-37219: Remove errorneous optimization for empty set differences.
bpo-36922: Slot functions optimize any callable with
Py_TPFLAGS_METHOD_DESCRIPTOR
instead of only instances offunction
.bpo-36974: The slot
tp_vectorcall_offset
is inherited unconditionally to supportsuper().__call__()
when the base class uses vectorcall.bpo-37160:
threading.get_native_id()
now also supports NetBSD.bpo-37077: Add
threading.get_native_id()
support for AIX. Patch by M. Felt
Library¶
bpo-37440: http.client now enables TLS 1.3 post-handshake authentication for default context or if a cert_file is passed to HTTPSConnection.
bpo-37437: Update vendorized expat version to 2.2.7.
bpo-37428: SSLContext.post_handshake_auth = True no longer sets SSL_VERIFY_POST_HANDSHAKE verify flag for client connections. Although the option is documented as ignored for clients, OpenSSL implicitly enables cert chain validation when the flag is set.
bpo-37420:
os.sched_setaffinity()
now correctly handles errors that arise during iteration over itsmask
argument. Patch by Brandt Bucher.bpo-37412: The
os.getcwdb()
function now uses the UTF-8 encoding on Windows, rather than the ANSI code page: see PEP 529 for the rationale. The function is no longer deprecated on Windows.bpo-29412: Fix IndexError in parsing a header value ending unexpectedly. Patch by Abhilash Raj.
bpo-36546: The dist argument for statistics.quantiles() is now positional only. The current name doesn’t reflect that the argument can be either a dataset or a distribution. Marking the parameter as positional avoids confusion and makes it possible to change the name later.
bpo-37394: Fix a bug that was causing the
queue
module to fail if the accelerator module was not available. Patch by Pablo Galindo.bpo-33972: Email with single part but content-type set to
multipart/*
doesn’t raise AttributeError anymore.bpo-37280: Use threadpool for reading from file for sendfile fallback mode.
bpo-37279: Fix asyncio sendfile support when sendfile sends extra data in fallback mode.
bpo-19865:
ctypes.create_unicode_buffer()
now also supports non-BMP characters on platforms with 16-bitwchar_t
(for example, Windows and AIX).bpo-37210: Allow pure Python implementation of
pickle
to work even when the C_pickle
module is unavailable.bpo-35922: Fix
RobotFileParser.crawl_delay()
andRobotFileParser.request_rate()
to returnNone
rather than raiseAttributeError
when no relevant rule is defined in the robots.txt file. Patch by Rémi Lapeyre.bpo-35766: Change the format of feature_version to be a (major, minor) tuple.
bpo-36607: Eliminate
RuntimeError
raised byasyncio.all_tasks()
if internal tasks weak set is changed by another thread during iteration.bpo-18748:
_pyio.IOBase
destructor now does nothing if getting theclosed
attribute fails to better mimick_io.IOBase
finalizer.bpo-36402: Fix a race condition at Python shutdown when waiting for threads. Wait until the Python thread state of all non-daemon threads get deleted (join all non-daemon threads), rather than just wait until non-daemon Python threads complete.
bpo-34886: Fix an unintended ValueError from
subprocess.run()
when checking for conflictinginput
andstdin
orcapture_output
andstdout
orstderr
args when they were explicitly provided but withNone
values within a passed in**kwargs
dict rather than as passed directly by name. Patch contributed by Rémi Lapeyre.bpo-37173: The exception message for
inspect.getfile()
now correctly reports the passed class rather than the builtins module.bpo-37178: Give math.perm() a one argument form that means the same as math.factorial().
bpo-37178: For math.perm(n, k), let k default to n, giving the same result as factorial.
bpo-37163: Deprecated passing
obj
argument ofdataclasses.replace()
as keyword argument.bpo-37165: Converted _collections._count_elements to use the Argument Clinic.
bpo-34767: Do not always create a
collections.deque
inasyncio.Lock
.bpo-37158: Speed-up statistics.fmean() by switching from a function to a generator.
bpo-37150:
argparse._ActionsContainer.add_argument
now throws error, if someone accidentally pass FileType class object instead of instance of FileType astype
argumentbpo-35621: Support running asyncio subprocesses when execution event loop in a thread on UNIX.
bpo-36520: Lengthy email headers with UTF-8 characters are now properly encoded when they are folded. Patch by Jeffrey Kintscher.
bpo-30835: Fixed a bug in email parsing where a message with invalid bytes in content-transfer-encoding of a multipart message can cause an AttributeError. Patch by Andrew Donnellan.
bpo-35805: Add parser for Message-ID header and add it to default HeaderRegistry. This should prevent folding of Message-ID using RFC 2048 encoded words.
bpo-35070: posix.getgrouplist() now works correctly when the user belongs to NGROUPS_MAX supplemental groups. Patch by Jeffrey Kintscher.
bpo-32627: Fix compile error when
_uuid
headers conflicting included.bpo-11122: Distutils won’t check for rpmbuild in specified paths only.
bpo-4963: Fixed non-deterministic behavior related to mimetypes extension mapping and module reinitialization.
Documentation¶
bpo-34903: Documented that in
datetime.datetime.strptime()
, the leading zero in some two-digit formats is optional. Patch by Mike Gleen.
Tests¶
bpo-37421: test_distutils.test_build_ext() is now able to remove the temporary directory on Windows: don’t import the newly built C extension (“xx”) in the current process, but test it in a separated process.
bpo-37421: test_concurrent_futures now cleans up multiprocessing to remove immediately temporary directories created by multiprocessing.util.get_temp_dir().
bpo-37421: test_winconsoleio doesn’t leak a temporary file anymore: use tempfile.TemporaryFile() to remove it when the test completes.
bpo-37421: multiprocessing tests now explicitly call
_run_finalizers()
to immediately remove temporary directories created by tests.bpo-37199: Fix test failures when IPv6 is unavailable or disabled.
bpo-37335: Remove no longer necessary code from c locale coercion tests
bpo-37421: Fix test_shutil to no longer leak temporary files.
bpo-37411: Fix test_wsgiref.testEnviron() to no longer depend on the environment variables (don’t fail if “X” variable is set).
bpo-37400: Fix test_os.test_chown(): use os.getgroups() rather than grp.getgrall() to get groups. Rename also the test to test_chown_gid().
bpo-37359: Add –cleanup option to python3 -m test to remove
test_python_*
directories of previous failed jobs. Add “make cleantest” to runpython3 -m test --cleanup
.bpo-37362: test_gdb no longer fails if it gets an “unexpected” message on stderr: it now ignores stderr. The purpose of test_gdb is to test that python-gdb.py commands work as expected, not to test gdb.
bpo-35998: Avoid TimeoutError in test_asyncio: test_start_tls_server_1()
bpo-37278: Fix test_asyncio ProactorLoopCtrlC: join the thread to prevent leaking a running thread and leaking a reference.
bpo-37261: Fix
test.support.catch_unraisable_exception()
: its __exit__() method now ignores unraisable exception raised when clearing itsunraisable
attribute.bpo-37169: Rewrite
_PyObject_IsFreed()
unit tests.bpo-37153:
test_venv.test_mutiprocessing()
now explicitly callspool.terminate()
to wait until the pool completes.bpo-28009: Modify the test_uuid logic to test when a program is available AND can be used to obtain a MACADDR as basis for an UUID. Patch by M. Felt
Build¶
bpo-37189: Many
PyRun_XXX()
functions likePyRun_String()
were no longer exported inlibpython38.dll
by mistake. Export them again to fix the ABI compatibiliy.
Windows¶
bpo-10945: Officially drop support for creating bdist_wininst installers on non-Windows systems.
bpo-37369: Fixes path for
sys.executable
when running from the Microsoft Store.bpo-37351: Removes libpython38.a from standard Windows distribution.
bpo-35360: Update Windows builds to use SQLite 3.28.0.
bpo-37267: On Windows,
os.dup()
no longer creates an inheritable fd when handling a character file.bpo-36779: Ensure
time.tzname
is correct on Windows when the active code page is set to CP_UTF7 or CP_UTF8.
macOS¶
bpo-34602: Avoid test suite failures on macOS by no longer calling resource.setrlimit to increase the process stack size limit at runtime. The runtime change is no longer needed since the interpreter is being built with a larger default stack size.
bpo-35360: Update macOS installer to use SQLite 3.28.0.
bpo-34631: Updated OpenSSL to 1.1.1c in macOS installer.
IDLE¶
bpo-37325: Fix tab focus traversal order for help source and custom run dialogs.
bpo-37321: Both subprocess connection error messages now refer to the ‘Startup failure’ section of the IDLE doc.
bpo-37177: Properly ‘attach’ search dialogs to their main window so that they behave like other dialogs and do not get hidden behind their main window.
bpo-37039: Adjust “Zoom Height” to individual screens by momemtarily maximizing the window on first use with a particular screen. Changing screen settings may invalidate the saved height. While a window is maximized, “Zoom Height” has no effect.
bpo-35763: Make calltip reminder about ‘/’ meaning positional-only less obtrusive by only adding it when there is room on the first line.
bpo-5680: Add ‘Run… Customized’ to the Run menu to run a module with customized settings. Any ‘command line arguments’ entered are added to sys.argv. One can suppress the normal Shell main module restart.
C API¶
bpo-36763: Add
PyConfig_SetWideStringList()
function.bpo-28805: The
METH_FASTCALL
calling convention has been documented.bpo-37221:
tp_print
is put back at the end of thePyTypeObject
structure to restore support for old code (in particular generated by Cython) settingtp_print = 0
. Note thattp_print
will be removed entirely in Python 3.9.bpo-37221: The new function
PyCode_NewWithPosOnlyArgs()
allows to create code objects likePyCode_New()
, but with an extra posonlyargcount parameter for indicating the number of positonal-only arguments.bpo-37191: Python.h does not need compiler support for intermingled declarations (GCC’s
-Wdeclaration-after-statement
), which were added in 3.8.0 Beta 1. Note that in Python 3.9, intermingled declarations will be needed again.bpo-37170: Fix the cast on error in
PyLong_AsUnsignedLongLongMask()
.
Python 3.8.0 beta 1¶
Release date: 2019-06-04
Security¶
bpo-35907: CVE-2019-9948: Avoid file reading by disallowing
local-file://
andlocal_file://
URL schemes inURLopener().open()
andURLopener().retrieve()
ofurllib.request
.bpo-33529: Prevent fold function used in email header encoding from entering infinite loop when there are too many non-ASCII characters in a header.
bpo-33164: Updated blake2 implementation which uses secure memset implementation provided by platform.
Core and Builtins¶
bpo-35814: Allow unpacking in the right hand side of annotated assignments. In particular,
t: Tuple[int, ...] = x, y, *z
is now allowed.bpo-37126: All structseq objects are now tracked by the garbage collector. Patch by Pablo Galindo.
bpo-37122: Make the co_argcount attribute of code objects represent the total number of positional arguments (including positional-only arguments). The value of co_posonlyargcount can be used to distinguish which arguments are positional only, and the difference (co_argcount - co_posonlyargcount) is the number of positional-or-keyword arguments. Patch by Pablo Galindo.
bpo-20092: Constructors of
int
,float
andcomplex
will now use the__index__()
special method, if available and the corresponding method__int__()
,__float__()
or__complex__()
is not available.bpo-37087: Add native thread ID (TID) support to OpenBSD.
bpo-26219: Implemented per opcode cache mechanism and
LOAD_GLOBAL
instruction use it.LOAD_GLOBAL
is now about 40% faster. Contributed by Yury Selivanov, and Inada Naoki.bpo-37072: Fix crash in PyAST_FromNodeObject() when flags is NULL.
bpo-37029: Freeing a great many small objects could take time quadratic in the number of arenas, due to using linear search to keep
obmalloc.c
’s list of usable arenas sorted by order of number of free memory pools. This is accomplished without search now, leaving the worst-case time linear in the number of arenas. For programs where this quite visibly matters (typically with more than 100 thousand small objects alive simultaneously), this can greatly reduce the time needed to release their memory.bpo-26423: Fix possible overflow in
wrap_lenfunc()
whensizeof(long) < sizeof(Py_ssize_t)
(e.g., 64-bit Windows).bpo-37050: Improve the AST for “debug” f-strings, which use ‘=’ to print out the source of the expression being evaluated. Delete expr_text from the FormattedValue node, and instead use a Constant string node (possibly merged with adjacent constant expressions inside the f-string).
bpo-22385: The
bytes.hex
,bytearray.hex
, andmemoryview.hex
methods as well as thebinascii.hexlify
andb2a_hex
functions now have the ability to include an optional separator between hex bytes. This functionality was inspired by MicroPython’s hexlify implementation.bpo-26836: Add
os.memfd_create()
.bpo-37032: Added new
replace()
method to the code type (types.CodeType
).bpo-37007: Implement
socket.if_nameindex()
,socket.if_nametoindex()
, andsocket.if_indextoname()
on Windows.bpo-36829:
PyErr_WriteUnraisable()
now creates a traceback object if there is no current traceback. Moreover, callPyErr_NormalizeException()
andPyException_SetTraceback()
to normalize the exception value. Ignore any error.bpo-36878: Only accept text after
# type: ignore
if the first character is ASCII. This is to disallow things like# type: ignoreé
.bpo-36878: Store text appearing after a
# type: ignore
comment in the AST. For example a type ignore like# type: ignore[E1000]
will have the string"[E1000]"
stored in its AST node.bpo-2180: Treat line continuation at EOF as a
SyntaxError
by Anthony Sottile.bpo-36907: Fix a crash when calling a C function with a keyword dict (
f(**kwargs)
) and changing the dictkwargs
while that function is running.bpo-36946: Fix possible signed integer overflow when handling slices.
bpo-36826: Add NamedExpression kind support to ast_unparse.c
bpo-1875: A
SyntaxError
is now raised if a code blocks that will be optimized away (e.g. if conditions that are always false) contains syntax errors. Patch by Pablo Galindo.bpo-36027: Allow computation of modular inverses via three-argument
pow
: the second argument is now permitted to be negative in the case where the first and third arguments are relatively prime.bpo-36861: Update the Unicode database to version 12.1.0.
bpo-28866: Avoid caching attributes of classes which type defines mro() to avoid a hard cache invalidation problem.
bpo-36851: The
FrameType
stack is now correctly cleaned up if the execution ends with a return and the stack is not empty.bpo-34616: The
compile()
builtin functions now support theast.PyCF_ALLOW_TOP_LEVEL_AWAIT
flag, which allow to compile sources that contains top-levelawait
,async with
orasync for
. This is useful to evaluate async-code from with an already async functions; for example in a custom REPL.bpo-36842: Implement PEP 578, adding sys.audit, io.open_code and related APIs.
bpo-27639: Correct return type for UserList slicing operations. Patch by Michael Blahay, Erick Cervantes, and vaultah
bpo-36737: Move PyRuntimeState.warnings into per-interpreter state (via “module state”).
bpo-36793: Removed
__str__
implementations from builtin typesbool
,int
,float
,complex
and few classes from the standard library. They now inherit__str__()
fromobject
.bpo-36817: Add a
=
feature f-strings for debugging. This can precede!s
,!r
, or!a
. It produces the text of the expression, followed by an equal sign, followed by the repr of the value of the expression. Sof'{3*9+15=}'
would be equal to the string'3*9+15=42'
. If=
is specified, the default conversion is set to!r
, unless a format spec is given, in which case the formatting behavior is unchanged, and __format__ will be used.bpo-24048: Save the live exception during import.c’s
remove_module()
.bpo-27987: pymalloc returns memory blocks aligned by 16 bytes, instead of 8 bytes, on 64-bit platforms to conform x86-64 ABI. Recent compilers assume this alignment more often. Patch by Inada Naoki.
bpo-36601: A long-since-meaningless check for
getpid() == main_pid
was removed from Python’s internal C signal handler.bpo-36594: Fix incorrect use of
%p
in format strings. Patch by Zackery Spytz.bpo-36045: builtins.help() now prefixes
async
for async functionsbpo-36084: Add native thread ID (TID) to threading.Thread objects (supported platforms: Windows, FreeBSD, Linux, macOS)
bpo-36035: Added fix for broken symlinks in combination with pathlib
bpo-35983: Added new trashcan macros to deal with a double deallocation that could occur when the
tp_dealloc
of a subclass calls thetp_dealloc
of a base class and that base class uses the trashcan mechanism. Patch by Jeroen Demeyer.bpo-20602: Do not clear
sys.flags
andsys.float_info
during shutdown. Patch by Zackery Spytz.bpo-26826: Expose
copy_file_range()
as a low level API in theos
module.bpo-32388: Remove cross-version binary compatibility requirement in tp_flags.
bpo-31862: Port binascii to PEP 489 multiphase initialization. Patch by Marcel Plch.
Library¶
bpo-37128: Added
math.perm()
.bpo-37120: Add SSLContext.num_tickets to control the number of TLSv1.3 session tickets.
bpo-12202: Fix the error handling in
msilib.SummaryInformation.GetProperty()
. Patch by Zackery Spytz.bpo-26835: The fcntl module now contains file sealing constants for sealing of memfds.
bpo-29262: Add
get_origin()
andget_args()
introspection helpers totyping
module.bpo-12639:
msilib.Directory.start_component()
no longer fails if keyfile is notNone
.bpo-36999: Add the
asyncio.Task.get_coro()
method to publicly expose the tasks’s coroutine object.bpo-35246: Make
asyncio.create_subprocess_exec()
accept path-like arguments.bpo-35279: Change default max_workers of
ThreadPoolExecutor
fromcpu_count() * 5
tomin(32, cpu_count() + 4))
. Previous value was unreasonably large on many cores machines.bpo-37076:
_thread.start_new_thread()
now logs uncaught exception raised by the function usingsys.unraisablehook()
, rather thansys.excepthook()
, so the hook gets access to the function which raised the exception.bpo-33725: On macOS, the
multiprocessing
module now uses spawn start method by default.bpo-37054: Fix destructor
_pyio.BytesIO
and_pyio.TextIOWrapper
: initialize their_buffer
attribute as soon as possible (in the class body), because it’s used by__del__()
which callsclose()
.bpo-37058: PEP 544: Add
Protocol
and@runtime_checkable
to thetyping
module.bpo-36933: The functions
sys.set_coroutine_wrapper
andsys.get_coroutine_wrapper
that were deprecated and marked for removal in 3.8 have been removed.bpo-37047: Handle late binding and attribute access in
unittest.mock.AsyncMock
setup for autospeccing. Document newly implemented async methods inunittest.mock.MagicMock
.bpo-37049: PEP 589: Add
TypedDict
to thetyping
module.bpo-37046: PEP 586: Add
Literal
to thetyping
module.bpo-37045: PEP 591: Add
Final
qualifier and@final
decorator to thetyping
module.bpo-37035: Don’t log OSError based exceptions if a fatal error has occurred in asyncio transport. Peer can generate almost any OSError, user cannot avoid these exceptions by fixing own code. Errors are still propagated to user code, it’s just logging them is pointless and pollute asyncio logs.
bpo-37001:
symtable.symtable()
now accepts the same input types for source code as the built-incompile()
function. Patch by Dino Viehland.bpo-37028: Implement asyncio REPL
bpo-37027: Return safe to use proxy socket object from transport.get_extra_info(‘socket’)
bpo-32528: Make asyncio.CancelledError a BaseException.
This will address the common mistake many asyncio users make: an “except Exception” clause breaking Tasks cancellation.
In addition to this change, we stop inheriting asyncio.TimeoutError and asyncio.InvalidStateError from their concurrent.futures.* counterparts. There’s no point for these exceptions to share the inheritance chain.
bpo-1230540: Add a new
threading.excepthook()
function which handles uncaughtthreading.Thread.run()
exception. It can be overridden to control how uncaughtthreading.Thread.run()
exceptions are handled.bpo-36996: Handle
unittest.mock.patch()
used as a decorator on async functions.bpo-37008: Add support for calling
next()
with the mock resulting fromunittest.mock.mock_open()
bpo-27737: Allow whitespace only header encoding in
email.header
- by Batuhan Taskayabpo-36969: PDB command
args
now display positional only arguments. Patch contributed by Rémi Lapeyre.bpo-36969: PDB command
args
now display keyword only arguments. Patch contributed by Rémi Lapeyre.bpo-36983: Add missing names to
typing.__all__
:ChainMap
,ForwardRef
,OrderedDict
- by Anthony Sottile.bpo-36972: Add SupportsIndex protocol to the typing module to allow type checking to detect classes that can be passed to
hex()
,oct()
andbin()
.bpo-32972: Implement
unittest.IsolatedAsyncioTestCase
to help testing asyncio-based code.bpo-36952:
fileinput.input()
andfileinput.FileInput
bufsize argument has been removed (was deprecated and ignored since Python 3.6), and as a result the mode and openhook arguments have been made keyword-only.bpo-36952: Starting with Python 3.3, importing ABCs from
collections
is deprecated, and import should be done fromcollections.abc
. Still being able to import fromcollections
was marked for removal in 3.8, but has been delayed to 3.9; documentation andDeprecationWarning
clarified.bpo-36949: Implement __repr__ for WeakSet objects.
bpo-36948: Fix
NameError
inurllib.request.URLopener.retrieve()
. Patch by Karthikeyan Singaravelan.bpo-33524: Fix the folding of email header when the max_line_length is 0 or None and the header contains non-ascii characters. Contributed by Licht Takeuchi (@Licht-T).
bpo-24564:
shutil.copystat()
now ignoreserrno.EINVAL
onos.setxattr()
which may occur when copying files on filesystems without extended attributes support.Original patch by Giampaolo Rodola, updated by Ying Wang.
bpo-36888: Python child processes can now access the status of their parent process using multiprocessing.process.parent_process
bpo-36921: Deprecate
@coroutine
for sake ofasync def
.bpo-25652: Fix bug in
__rmod__
ofUserString
- by Batuhan Taskaya.bpo-36916: Remove a message about an unhandled exception in a task when writer.write() is used without await and writer.drain() fails with an exception.
bpo-36889: Introduce
asyncio.Stream
class that mergesasyncio.StreamReader
andasyncio.StreamWriter
functionality.asyncio.Stream
can work in readonly, writeonly and readwrite modes. Provideasyncio.connect()
,asyncio.connect_unix()
,asyncio.connect_read_pipe()
andasyncio.connect_write_pipe()
factories to openasyncio.Stream
connections. Provideasyncio.StreamServer
andUnixStreamServer
to serve servers with asyncio.Stream API. Modifyasyncio.create_subprocess_shell()
andasyncio.create_subprocess_exec()
to useasyncio.Stream
instead of deprecatedStreamReader
andStreamWriter
. Deprecateasyncio.StreamReader
andasyncio.StreamWriter
. Deprecate usage of private classes, e.g.asyncio.FlowControlMixing
andasyncio.StreamReaderProtocol
outside of asyncio package.bpo-36845: Added validation of integer prefixes to the construction of IP networks and interfaces in the ipaddress module.
bpo-23378: Add an extend action to argparser.
bpo-36867: Fix a bug making a SharedMemoryManager instance and its parent process use two separate resource_tracker processes.
bpo-23896: Adds a grammar to lib2to3.pygram that contains exec as a function not as statement.
bpo-36895: The function
time.clock()
was deprecated in 3.3 in favor oftime.perf_counter()
and marked for removal in 3.8, it has removed.bpo-35545: Fix asyncio discarding IPv6 scopes when ensuring hostname resolutions internally
bpo-36887: Add new function
math.isqrt()
to compute integer square roots.bpo-34632: Introduce the
importlib.metadata
module with (provisional) support for reading metadata from third-party packages.bpo-36878: When using
type_comments=True
inast.parse
, treat# type: ignore
followed by a non-alphanumeric character and then arbitrary text as a type ignore, instead of requiring nothing but whitespace or another comment. This is to permit formations such as# type: ignore[E1000]
.bpo-36778:
cp65001
encoding (Windows code page 65001) becomes an alias toutf_8
encoding.bpo-36867: The multiprocessing.resource_tracker replaces the multiprocessing.semaphore_tracker module. Other than semaphores, resource_tracker also tracks shared_memory segments.
bpo-30262: The
Cache
andStatement
objects of thesqlite3
module are not exposed to the user. Patch by Aviv Palivoda.bpo-24538: In
shutil.copystat()
, first copy extended file attributes and then file permissions, since extended attributes can only be set on the destination while it is still writeable.bpo-36829: Add new
sys.unraisablehook()
function which can be overridden to control how “unraisable exceptions” are handled. It is called when an exception has occurred but there is no way for Python to handle it. For example, when a destructor raises an exception or during garbage collection (gc.collect()
).bpo-36832: Introducing
zipfile.Path
, a pathlib-compatible wrapper for traversing zip files.bpo-36814: Fix an issue where os.posix_spawnp() would incorrectly raise a TypeError when file_actions is None.
bpo-33110: Handle exceptions raised by functions added by concurrent.futures add_done_callback correctly when the Future has already completed.
bpo-26903: Limit
max_workers
inProcessPoolExecutor
to 61 to work around a WaitForMultipleObjects limitation.bpo-36813: Fix
QueueListener
to callqueue.task_done()
upon stopping. Patch by Bar Harel.bpo-36806: Forbid creation of asyncio stream objects like StreamReader, StreamWriter, Process, and their protocols outside of asyncio package.
bpo-36802: Provide both sync and async calls for StreamWriter.write() and StreamWriter.close()
bpo-36801: Properly handle SSL connection closing in asyncio StreamWriter.drain() call.
bpo-36785: Implement PEP 574 (pickle protocol 5 with out-of-band buffers).
bpo-36772: functools.lru_cache() can now be used as a straight decorator in addition to its existing usage as a function that returns a decorator.
bpo-6584: Add a
BadGzipFile
exception to thegzip
module.bpo-36748: Optimized write buffering in C implementation of
TextIOWrapper
. Writing ASCII string toTextIOWrapper
with ascii, latin1, or utf-8 encoding is about 20% faster. Patch by Inada Naoki.bpo-8138: Don’t mark
wsgiref.simple_server.SimpleServer
as multi-threaded sincewsgiref.simple_server.WSGIServer
is single-threaded.bpo-22640:
py_compile.compile()
now supports silent mode. Patch by Joannah Nanjekyebpo-29183: Fix double exceptions in
wsgiref.handlers.BaseHandler
by calling itsclose()
method only when no exception is raised.bpo-36548: Improved the repr of regular expression flags.
bpo-36542: The signature of Python functions can now be overridden by specifying the
__text_signature__
attribute.bpo-36533: Reinitialize logging.Handler locks in forked child processes instead of attempting to acquire them all in the parent before forking only to be released in the child process. The acquire/release pattern was leading to deadlocks in code that has implemented any form of chained logging handlers that depend upon one another as the lock acquisition order cannot be guaranteed.
bpo-35252: Throw a TypeError instead of an AssertionError when using an invalid type annotation with singledispatch.
bpo-35900: Allow reduction methods to return a 6-item tuple where the 6th item specifies a custom state-setting method that’s called instead of the regular
__setstate__
method.bpo-35900: enable custom reduction callback registration for functions and classes in _pickle.c, using the new Pickler’s attribute
reducer_override
bpo-36368: Fix a bug crashing SharedMemoryManager instances in interactive sessions after a ctrl-c (KeyboardInterrupt) was sent
bpo-31904: Fix mmap fail for VxWorks
bpo-27497:
csv.DictWriter.writeheader()
now returns the return value of the underlyingcsv.Writer.writerow()
method. Patch contributed by Ashish Nitin Patil.bpo-36239: Parsing .mo files now ignores comments starting and ending with #-#-#-#-#.
bpo-26707: Enable plistlib to read and write binary plist files that were created as a KeyedArchive file. Specifically, this allows the plistlib to process 0x80 tokens as UID objects.
bpo-31904: Add posix module support for VxWorks.
bpo-35125: Asyncio: Remove inner callback on outer cancellation in shield
bpo-35721: Fix
asyncio.SelectorEventLoop.subprocess_exec()
leaks file descriptors ifPopen
fails and called withstdin=subprocess.PIPE
. Patch by Niklas Fiekas.bpo-31855:
unittest.mock.mock_open()
results now respects the argument of read([size]). Patch contributed by Rémi Lapeyre.bpo-35431: Implement
math.comb()
that returns binomial coefficient, that computes the number of ways to choose k items from n items without repetition and without order. Patch by Yash Aggarwal and Keller Fuchs.bpo-26660: Fixed permission errors in
TemporaryDirectory
clean up. PreviouslyTemporaryDirectory.cleanup()
failed when non-writeable or non-searchable files or directories were created inside a temporary directory.bpo-34271: Add debugging helpers to ssl module. It’s now possible to dump key material and to trace TLS protocol. The default and stdlib contexts also support SSLKEYLOGFILE env var.
bpo-26467: Added AsyncMock to support using unittest to mock asyncio coroutines. Patch by Lisa Roach.
bpo-33569: dataclasses.InitVar: Exposes the type used to create the init var.
bpo-34424: Fix serialization of messages containing encoded strings when the policy.linesep is set to a multi-character string. Patch by Jens Troeger.
bpo-34303: Performance of
functools.reduce()
is slightly improved. Patch by Sergey Fedoseev.bpo-33361: Fix a bug in
codecs.StreamRecoder
where seeking might leave old data in a buffer and break subsequent read calls. Patch by Ammar Askar.bpo-22454: The
shlex
module now exposesshlex.join()
, the inverse ofshlex.split()
. Patch by Bo Bayles.bpo-31922:
asyncio.AbstractEventLoop.create_datagram_endpoint()
: Do not connect UDP socket when broadcast is allowed. This allows to receive replies after a UDP broadcast.bpo-24882: Change ThreadPoolExecutor to use existing idle threads before spinning up new ones.
bpo-31961: Added support for bytes and path-like objects in
subprocess.Popen()
on Windows. The args parameter now accepts a path-like object if shell isFalse
and a sequence containing bytes and path-like objects. The executable parameter now accepts a bytes and path-like object. The cwd parameter now accepts a bytes object. Based on patch by Anders Lorentsen.bpo-33123:
pathlib.Path.unlink
now accepts a missing_ok parameter to avoid aFileNotFoundError
from being raised. Patch by Robert Buchholz.bpo-32941: Allow
mmap.mmap
objects to access the madvise() system call (throughmmap.mmap.madvise()
).bpo-22102: Added support for ZIP files with disks set to 0. Such files are commonly created by builtin tools on Windows when use ZIP64 extension. Patch by Francisco Facioni.
bpo-32515: trace.py can now run modules via python3 -m trace -t –module module_name
bpo-32299: Changed
unittest.mock.patch.dict()
to return the patched dictionary when used as context manager. Patch by Vadim Tsander.bpo-27141: Added a
__copy__()
tocollections.UserList
andcollections.UserDict
in order to correctly implement shallow copying of the objects. Patch by Bar Harel.bpo-31829:
\r
,\0
and\x1a
(end-of-file on Windows) are now escaped in protocol 0 pickles of Unicode strings. This allows to load them without loss from files open in text mode in Python 2.bpo-23395:
_thread.interrupt_main()
now avoids setting the Python error status if theSIGINT
signal is ignored or not handled by Python.
Documentation¶
bpo-36896: Clarify that some types have unstable constructor signature between Python versions.
bpo-36686: Improve documentation of the stdin, stdout, and stderr arguments of the
asyncio.subprocess_exec
function to specify which values are supported. Also mention that decoding as text is not supported.Add a few tests to verify that the various values passed to the std* arguments actually work.
bpo-36984: Improve version added references in
typing
module - by Anthony Sottile.bpo-36868: What’s new now mentions SSLContext.hostname_checks_common_name instead of SSLContext.host_flags.
bpo-35924: Add a note to the
curses.addstr()
documentation to warn that multiline strings can cause segfaults because of an ncurses bug.bpo-36783: Added C API Documentation for Time_FromTimeAndFold and PyDateTime_FromDateAndTimeAndFold as per PEP 495. Patch by Edison Abahurire.
bpo-36797: More of the legacy distutils documentation has been either pruned, or else more clearly marked as being retained solely until the setuptools documentation covers it independently.
bpo-22865: Add detail to the documentation on the
pty.spawn
function.bpo-35397: Remove deprecation and document urllib.parse.unwrap(). Patch contributed by Rémi Lapeyre.
bpo-32995: Added the context variable in glossary.
bpo-33519: Clarify that
copy()
is not part of theMutableSequence
ABC.bpo-33482: Make
codecs.StreamRecoder.writelines
take a list of bytes.bpo-25735: Added documentation for func factorial to indicate that returns integer values
bpo-20285: Expand object.__doc__ (docstring) to make it clearer. Modify pydoc.py so that help(object) lists object methods (for other classes, help omits methods of the object base class.)
Tests¶
bpo-37069: Modify test_coroutines, test_cprofile, test_generators, test_raise, test_ssl and test_yield_from to use
test.support.catch_unraisable_exception()
rather thantest.support.captured_stderr()
.bpo-37098: Fix test_memfd_create on older Linux Kernels.
bpo-37081: Test with OpenSSL 1.1.1c
bpo-36829: Add
test.support.catch_unraisable_exception()
: context manager catching unraisable exception usingsys.unraisablehook()
.bpo-36915: The main regrtest process now always removes all temporary directories of worker processes even if they crash or if they are killed on KeyboardInterrupt (CTRL+c).
bpo-36719: “python3 -m test -jN …” now continues the execution of next tests when a worker process crash (CHILD_ERROR state). Previously, the test suite stopped immediately. Use –failfast to stop at the first error.
bpo-36816: Update Lib/test/selfsigned_pythontestdotnet.pem to match self-signed.pythontest.net’s new TLS certificate.
bpo-35925: Skip httplib and nntplib networking tests when they would otherwise fail due to a modern OS or distro with a default OpenSSL policy of rejecting connections to servers with weak certificates.
bpo-36782: Add tests for several C API functions in the
datetime
module. Patch by Edison Abahurire.bpo-36342: Fix test_multiprocessing in test_venv if platform lacks functioning sem_open.
Build¶
bpo-36721: To embed Python into an application, a new
--embed
option must be passed topython3-config --libs --embed
to get-lpython3.8
(link the application to libpython). To support both 3.8 and older, trypython3-config --libs --embed
first and fallback topython3-config --libs
(without--embed
) if the previous command fails.Add a pkg-config
python-3.8-embed
module to embed Python into an application:pkg-config python-3.8-embed --libs
includes-lpython3.8
. To support both 3.8 and older, trypkg-config python-X.Y-embed --libs
first and fallback topkg-config python-X.Y --libs
(without--embed
) if the previous command fails (replaceX.Y
with the Python version).On the other hand,
pkg-config python3.8 --libs
no longer contains-lpython3.8
. C extensions must not be linked to libpython (except on Android, case handled by the script); this change is backward incompatible on purpose.bpo-36786: “make install” now runs compileall in parallel.
Windows¶
macOS¶
bpo-36231: Support building Python on macOS without /usr/include installed. As of macOS 10.14, system header files are only available within an SDK provided by either the Command Line Tools or the Xcode app.
IDLE¶
bpo-35610: Replace now redundant .context_use_ps1 with .prompt_last_line. This finishes change started in bpo-31858.
bpo-37038: Make idlelib.run runnable; add test clause.
bpo-36958: Print any argument other than None or int passed to SystemExit or sys.exit().
bpo-36807: When saving a file, call os.fsync() so bits are flushed to e.g. USB drive.
bpo-32411: In browser.py, remove extraneous sorting by line number since dictionary was created in line number order.
Tools/Demos¶
bpo-37053: Handle strings like u”bar” correctly in Tools/parser/unparse.py. Patch by Chih-Hsuan Yen.
C API¶
bpo-36763: Implement the PEP 587 “Python Initialization Configuration”.
bpo-36379: Fix crashes when attempting to use the modulo parameter when
__ipow__
is implemented in C.bpo-37107: Update
PyObject_CallMethodObjArgs()
and_PyObject_CallMethodIdObjArgs
to use_PyObject_GetMethod
to avoid creating a bound method object in many cases. Patch by Michael J. Sullivan.bpo-36974: Implement PEP 590: Vectorcall: a fast calling protocol for CPython. This is a new protocol to optimize calls of custom callable objects.
bpo-36763:
Py_Main()
now returns the exitcode rather than callingPy_Exit(exitcode)
when callingPyErr_Print()
if the current exception type isSystemExit
.bpo-36922: Add new type flag
Py_TPFLAGS_METHOD_DESCRIPTOR
for objects behaving like unbound methods. These are objects supporting the optimization given by theLOAD_METHOD
/CALL_METHOD
opcodes. See PEP 590.bpo-36728: The
PyEval_ReInitThreads()
function has been removed from the C API. It should not be called explicitly: usePyOS_AfterFork_Child()
instead.
Python 3.8.0 alpha 4¶
Release date: 2019-05-06
Security¶
bpo-36742: Fixes mishandling of pre-normalization characters in urlsplit().
bpo-30458: Address CVE-2019-9740 by disallowing URL paths with embedded whitespace or control characters through into the underlying http client request. Such potentially malicious header injection URLs now cause an http.client.InvalidURL exception to be raised.
bpo-35755:
shutil.which()
now usesos.confstr("CS_PATH")
if available and if thePATH
environment variable is not set. Remove also the current directory fromposixpath.defpath
. On Unix,shutil.which()
and thesubprocess
module no longer search the executable in the current directory if thePATH
environment variable is not set.
Core and Builtins¶
bpo-36722: In debug build, import now also looks for C extensions compiled in release mode and for C extensions compiled in the stable ABI.
bpo-32849: Fix Python Initialization code on FreeBSD to detect properly when stdin file descriptor (fd 0) is invalid.
bpo-36623: Remove parser headers and related function declarations that lack implementations after the removal of pgen.
bpo-20180:
dict.pop()
is now up to 33% faster thanks to Argument Clinic. Patch by Inada Naoki.bpo-36611: Debug memory allocators: disable serialno field by default from debug hooks on Python memory allocators to reduce the memory footprint by 5%. Enable
tracemalloc
to get the traceback where a memory block has been allocated when a fatal memory error is logged to decide where to put a breakpoint. Compile Python withPYMEM_DEBUG_SERIALNO
defined to get back the field.bpo-36588: On AIX,
sys.platform
doesn’t contain the major version anymore. Always return'aix'
, instead of'aix3'
..'aix7'
. Since older Python versions include the version number, it is recommended to always usesys.platform.startswith('aix')
. Contributed by M. Felt.bpo-36549: Change str.capitalize to use titlecase for the first character instead of uppercase.
bpo-36540: Implement PEP 570 (Python positional-only parameters). Patch by Pablo Galindo.
bpo-36475:
PyEval_AcquireLock()
andPyEval_AcquireThread()
now terminate the current thread if called while the interpreter is finalizing, making them consistent withPyEval_RestoreThread()
,Py_END_ALLOW_THREADS()
, andPyGILState_Ensure()
.bpo-36504: Fix signed integer overflow in _ctypes.c’s
PyCArrayType_new()
.bpo-20844: Fix running script with encoding cookie and LF line ending may fail on Windows.
bpo-24214: Fixed support of the surrogatepass error handler in the UTF-8 incremental decoder.
bpo-36452: Changing
dict
keys during iteration of the dict itself,keys()
,values()
, oritems()
will now be detected in certain corner cases where keys are deleted/added so that the number of keys isn’t changed. ARuntimeError
will be raised afterlen(dict)
iterations. Contributed by Thomas Perl.bpo-36459: Fix a possible double
PyMem_FREE()
due to tokenizer.c’stok_nextc()
.bpo-36433: Fixed TypeError message in classmethoddescr_call.
bpo-36430: Fix a possible reference leak in
itertools.count()
.bpo-36440: Include node names in
ParserError
messages, instead of numeric IDs. Patch by A. Skrobov.bpo-36143: Regenerate
keyword
from the Grammar and Tokens file using pgen. Patch by Pablo Galindo.bpo-18372: Add missing
PyObject_GC_Track()
calls in thepickle
module. Patch by Zackery Spytz.
Library¶
bpo-35952: Fix pythoninfo when the compiler is missing.
bpo-28238: The
.find*()
methods of xml.etree.ElementTree can now search for wildcards like{*}tag
and{ns}*
that match a tag in any namespace or all tags in a namespace. Patch by Stefan Behnel.bpo-26978:
pathlib.path.link_to()
is now implemented. It creates a hard link pointing to a path.bpo-1613500:
fileinput.FileInput
now uses the input file mode to correctly set the output file mode (previously it was hardcoded to'w'
) wheninplace=True
is passed to its constructor.bpo-36734: Fix compilation of
faulthandler.c
on HP-UX. Initializestack_t current_stack
to zero usingmemset()
.bpo-13611: The xml.etree.ElementTree packages gained support for C14N 2.0 serialisation. Patch by Stefan Behnel.
bpo-36669: Add missing matrix multiplication operator support to weakref.proxy.
bpo-36676: The XMLParser() in xml.etree.ElementTree provides namespace prefix context to the parser target if it defines the callback methods “start_ns()” and/or “end_ns()”. Patch by Stefan Behnel.
bpo-36673: The TreeBuilder and XMLPullParser in xml.etree.ElementTree gained support for parsing comments and processing instructions. Patch by Stefan Behnel.
bpo-36650: The C version of functools.lru_cache() was treating calls with an empty
**kwargs
dictionary as being distinct from calls with no keywords at all. This did not result in an incorrect answer, but it did trigger an unexpected cache miss.bpo-28552: Fix
distutils.sysconfig
ifsys.executable
isNone
or an empty string: useos.getcwd()
to initializeproject_base
. Fix also the distutils build command: don’t usesys.executable
if it isNone
or an empty string.bpo-35755:
shutil.which()
anddistutils.spawn.find_executable()
now useos.confstr("CS_PATH")
if available instead ofos.defpath
, if thePATH
environment variable is not set. Moreover, don’t useos.confstr("CS_PATH")
noros.defpath
if thePATH
environment variable is set to an empty string.bpo-25430: improve performance of
IPNetwork.__contains__()
bpo-30485: Path expressions in xml.etree.ElementTree can now avoid explicit namespace prefixes for tags (or the “{namespace}tag” notation) by passing a default namespace with an empty string prefix.
bpo-36613: Fix
asyncio
wait() not removing callback if exceptionbpo-36598: Fix
isinstance
check for Mock objects with spec when the code is executed under tracing. Patch by Karthikeyan Singaravelan.bpo-18748: In development mode (
-X
dev
) and in debug build, theio.IOBase
destructor now logsclose()
exceptions. These exceptions are silent by default in release mode.bpo-36575: The
_lsprof
module now uses internal timer same totime.perf_counter()
by default.gettimeofday(2)
was used on Unix. New timer has better resolution on most Unix platforms and timings are no longer impacted by system clock updates sinceperf_counter()
is monotonic. Patch by Inada Naoki.bpo-33461:
json.loads
now emitsDeprecationWarning
whenencoding
option is specified. Patch by Matthias Bussonnier.bpo-36559: The random module now prefers the lean internal _sha512 module over hashlib for seed(version=2) to optimize import time.
bpo-17561: Set backlog=None as the default for socket.create_server.
bpo-34373: Fix
time.mktime()
error handling on AIX for year before 1970.bpo-36232: Improve error message when trying to open existing DBM database that actually doesn’t exist. Patch by Marco Rougeth.
bpo-36546: Add statistics.quantiles()
bpo-36050: Optimized
http.client.HTTPResponse.read()
for large response. Patch by Inada Naoki.bpo-36522: If debuglevel is set to >0 in
http.client
, print all values for headers with multiple values for the same header name. Patch by Matt Houglum.bpo-36492: Deprecated passing required arguments like func as keyword arguments in functions which should accept arbitrary keyword arguments and pass them to other function. Arbitrary keyword arguments (even with names “self” and “func”) can now be passed to these functions if the required arguments are passed as positional arguments.
bpo-27181: Add statistics.geometric_mean().
bpo-30427:
os.path.normcase()
relies onos.fspath()
to check the type of its argument. Redundant checks have been removed from itsposixpath.normcase()
andntpath.normcase()
implementations. Patch by Wolfgang Maier.bpo-36385: Stop rejecting IPv4 octets for being ambiguously octal. Leading zeros are ignored, and no longer are assumed to specify octal octets. Octets are always decimal numbers. Octets must still be no more than three digits, including leading zeroes.
bpo-36434: Errors during writing to a ZIP file no longer prevent to properly close it.
bpo-36407: Fixed wrong indentation writing for CDATA section in xml.dom.minidom. Patch by Vladimir Surjaninov.
bpo-36326: inspect.getdoc() can now find docstrings for member objects when __slots__ is a dictionary.
bpo-36366: Calling
stop()
on an unstarted or stoppedunittest.mock.patch()
object will now returnNone
instead of raisingRuntimeError
, making the method idempotent. Patch by Karthikeyan Singaravelan.bpo-36348: The
imap.IMAP4.logout()
method no longer ignores silently arbitrary exceptions.bpo-31904: Add time module support and fix test_time faiures for VxWorks.
bpo-36227: Added support for keyword arguments
default_namespace
andxml_declaration
in functions ElementTree.tostring() and ElementTree.tostringlist().bpo-36004: Added new alternate constructors
datetime.date.fromisocalendar()
anddatetime.datetime.fromisocalendar()
, which construct date objects from ISO year, week number and weekday; these are the inverse of each class’sisocalendar
method. Patch by Paul Ganssle.bpo-35936:
modulefinder
no longer depends on the deprecatedimp
module, and the initializer formodulefinder.ModuleFinder
now has immutable default arguments. Patch by Brandt Bucher.bpo-35376:
modulefinder
correctly handles modules that have the same name as a bad package. Patch by Brandt Bucher.bpo-17396:
modulefinder
no longer crashes when encountering syntax errors in followed imports. Patch by Brandt Bucher.bpo-35934: Added
create_server()
andhas_dualstack_ipv6()
convenience functions to automate the necessary tasks usually involved when creating a server socket, including accepting both IPv4 and IPv6 connections on the same socket. (Contributed by Giampaolo Rodola in bpo-17561.)bpo-23078: Add support for
classmethod()
andstaticmethod()
tounittest.mock.create_autospec()
. Initial patch by Felipe Ochoa.bpo-35416: Fix potential resource warnings in distutils. Patch by Mickaël Schoentgen.
bpo-25451: Add transparency methods to
tkinter.PhotoImage
. Patch by Zackery Spytz.bpo-35082: Don’t return deleted attributes when calling dir on a
unittest.mock.Mock
.bpo-34547:
wsgiref.handlers.BaseHandler
now handles abrupt client connection terminations gracefully. Patch by Petter Strandmark.bpo-31658:
xml.sax.parse()
now supports path-like. Patch by Mickaël Schoentgen.bpo-34139: Remove stale unix datagram socket before binding
bpo-33530: Implemented Happy Eyeballs in
asyncio.create_connection()
. Added two new arguments, happy_eyeballs_delay and interleave, to specify Happy Eyeballs behavior.bpo-33291: Do not raise AttributeError when calling the inspect functions isgeneratorfunction, iscoroutinefunction, isasyncgenfunction on a method created from an arbitrary callable. Instead, return False.
bpo-31310: Fix the multiprocessing.semaphore_tracker so it is reused by child processes
bpo-31292: Fix
setup.py check --restructuredtext
for files containinginclude
directives.
Documentation¶
bpo-36625: Remove obsolete comments from docstrings in fractions.Fraction
bpo-30840: Document relative imports
bpo-36523: Add docstring for io.IOBase.writelines().
bpo-36425: New documentation translation: Simplified Chinese.
bpo-36345: Avoid the duplication of code from
Tools/scripts/serve.py
in using theliteralinclude
directive for the basic wsgiref-based web server in the documentation ofwsgiref
. Contributed by Stéphane Wirtel.bpo-36345: Using the code of the
Tools/scripts/serve.py
script as an example in thewsgiref
documentation. Contributed by Stéphane Wirtel.bpo-36157: Added Documention for PyInterpreterState_Main().
bpo-33043: Updates the docs.python.org page with the addition of a ‘Contributing to Docs’ link at the end of the page (between ‘Reporting Bugs’ and ‘About Documentation’). Updates the ‘Found a Bug’ page with additional links and information in the Documentation Bugs section.
bpo-35581: @typing.type_check_only now allows type stubs to mark functions and classes not available during runtime.
bpo-33832: Add glossary entry for ‘magic method’.
bpo-32913: Added re.Match.groupdict example to regex HOWTO.
Tests¶
bpo-36719: regrtest now always detects uncollectable objects. Previously, the check was only enabled by
--findleaks
. The check now also works with-jN/--multiprocess N
.--findleaks
becomes a deprecated alias to--fail-env-changed
.bpo-36725: When using mulitprocessing mode (-jN), regrtest now better reports errors if a worker process fails, and it exits immediately on a worker thread failure or when interrupted.
bpo-36454: Change test_time.test_monotonic() to test only the lower bound of elapsed time after a sleep command rather than the upper bound. This prevents unnecessary test failures on slow buildbots. Patch by Victor Stinner.
bpo-32424: Improve test coverage for xml.etree.ElementTree. Patch by Gordon P. Hemsley.
bpo-32424: Fix typo in test_cyclic_gc() test for xml.etree.ElementTree. Patch by Gordon P. Hemsley.
bpo-36635: Add a new
_testinternalcapi
module to test the internal C API.bpo-36629: Fix
test_imap4_host_default_value()
oftest_imaplib
: catch alsoerrno.ENETUNREACH
error.bpo-36611: Fix
test_sys.test_getallocatedblocks()
whentracemalloc
is enabled.bpo-36560: Fix reference leak hunting in regrtest: compute also deltas (of reference count, allocated memory blocks, file descriptor count) during warmup, to ensure that everything is initialized before starting to hunt reference leaks.
bpo-36565: Fix reference hunting (
python3 -m test -R 3:3
) when Python has no built-in abc module.bpo-31904: Port test_resource to VxWorks: skip tests cases setting RLIMIT_FSIZE and RLIMIT_CPU.
bpo-31904: Fix test_tabnanny on VxWorks: adjust ENOENT error message.
bpo-36436: Fix
_testcapi.pymem_buffer_overflow()
: handle memory allocation failure.bpo-31904: Fix test_utf8_mode on VxWorks: Python always use UTF-8 on VxWorks.
bpo-36341: Fix tests that may fail with PermissionError upon calling bind() on AF_UNIX sockets.
Build¶
bpo-36747: Remove the stale scriptsinstall Makefile target.
bpo-21536: On Unix, C extensions are no longer linked to libpython except on Android and Cygwin.
It is now possible for a statically linked Python to load a C extension built using a shared library Python.
When Python is embedded,
libpython
must not be loaded withRTLD_LOCAL
, butRTLD_GLOBAL
instead. Previously, usingRTLD_LOCAL
, it was already not possible to load C extensions which were not linked tolibpython
, such as C extensions of the standard library built by the*shared*
section ofModules/Setup
.distutils, python-config and python-config.py have been modified.
bpo-36707:
./configure --with-pymalloc
no longer adds them
flag to SOABI (sys.implementation.cache_tag). Enabling or disabling pymalloc has no impact on the ABI.bpo-36635: Change
PyAPI_FUNC(type)
,PyAPI_DATA(type)
andPyMODINIT_FUNC
macros ofpyport.h
whenPy_BUILD_CORE_MODULE
is defined. ThePy_BUILD_CORE_MODULE
define must be now be used to build a C extension as a dynamic library accessing Python internals: export the PyInit_xxx() function in DLL exports on Windows.bpo-31904: Don’t build the
_crypt
extension on VxWorks.bpo-36618: Add
-fmax-type-align=8
to CFLAGS when clang compiler is detected. The pymalloc memory allocator aligns memory on 8 bytes. On x86-64, clang expects alignment on 16 bytes by default and so uses MOVAPS instruction which can lead to segmentation fault. Instruct clang that Python is limited to alignment on 8 bytes to use MOVUPS instruction instead: slower but don’t trigger a SIGSEGV if the memory is not aligned on 16 bytes. Sadly, the flag must be added toCFLAGS
and not justCFLAGS_NODIST
, since third party C extensions can have the same issue.bpo-36605:
make tags
andmake TAGS
now also parseModules/_io/*.c
andModules/_io/*.h
.bpo-36465: Release builds and debug builds are now ABI compatible: defining the
Py_DEBUG
macro no longer implies thePy_TRACE_REFS
macro, which introduces the only ABI incompatibility. ThePy_TRACE_REFS
macro, which adds thesys.getobjects()
function and thePYTHONDUMPREFS
environment variable, can be set using the new./configure --with-trace-refs
build option.bpo-36577: setup.py now correctly reports missing OpenSSL headers and libraries again.
bpo-36544: Fix regression introduced in bpo-36146 refactoring setup.py
bpo-36508:
python-config --ldflags
no longer includes flags of theLINKFORSHARED
variable. TheLINKFORSHARED
variable must only be used to build executables.bpo-36503: Remove references to “aix3” and “aix4”. Patch by M. Felt.
Windows¶
bpo-35920: Added platform.win32_edition() and platform.win32_is_iot(). Added support for cross-compiling packages for Windows ARM32. Skip tests that are not expected to work on Windows IoT Core ARM32.
bpo-36649: Remove trailing spaces for registry keys when installed via the Store.
bpo-34144: Fixed activate.bat to correctly update codepage when chcp.com returns dots in output. Patch by Lorenz Mende.
bpo-36509: Added preset-iot layout for Windows IoT ARM containers. This layout doesn’t contain UI components like tkinter or IDLE. It also doesn’t contain files to support on-target builds since Windows ARM32 builds must be cross-compiled when using MSVC.
bpo-35941: enum_certificates function of the ssl module now returns certificates from all available certificate stores inside windows in a query instead of returning only certificates from the system wide certificate store. This includes certificates from these certificate stores: local machine, local machine enterprise, local machine group policy, current user, current user group policy, services, users. ssl.enum_crls() function is changed in the same way to return all certificate revocation lists inside the windows certificate revocation list stores.
bpo-36441: Fixes creating a venv when debug binaries are installed.
bpo-36085: Enable better DLL resolution on Windows by using safe DLL search paths and adding
os.add_dll_directory()
.bpo-36010: Add the venv standard library module to the nuget distribution for Windows.
bpo-29515: Add the following socket module constants on Windows: IPPROTO_AH IPPROTO_CBT IPPROTO_DSTOPTS IPPROTO_EGP IPPROTO_ESP IPPROTO_FRAGMENT IPPROTO_GGP IPPROTO_HOPOPTS IPPROTO_ICLFXBM IPPROTO_ICMPV6 IPPROTO_IDP IPPROTO_IGMP IPPROTO_IGP IPPROTO_IPV4 IPPROTO_IPV6 IPPROTO_L2TP IPPROTO_MAX IPPROTO_ND IPPROTO_NONE IPPROTO_PGM IPPROTO_PIM IPPROTO_PUP IPPROTO_RDP IPPROTO_ROUTING IPPROTO_SCTP IPPROTO_ST
bpo-35947: Added current version of libffi to cpython-source-deps. Change _ctypes to use current version of libffi on Windows.
bpo-34060: Report system load when running test suite on Windows. Patch by Ammar Askar. Based on prior work by Jeremy Kloth.
bpo-31512: With the Windows 10 Creators Update, non-elevated users can now create symlinks as long as the computer has Developer Mode enabled.
macOS¶
IDLE¶
bpo-36429: Fix starting IDLE with pyshell. Add idlelib.pyshell alias at top; remove pyshell alias at bottom. Remove obsolete __name__==’__main__’ command.
Tools/Demos¶
bpo-14546: Fix the argument handling in Tools/scripts/lll.py.
C API¶
bpo-36763: Fix memory leak in
Py_SetStandardStreamEncoding()
: release memory if the function is called twice.bpo-36641:
PyDoc_VAR(name)
andPyDoc_STRVAR(name,str)
now createstatic const char name[]
instead ofstatic char name[]
. Patch by Inada Naoki.bpo-36389: Change the value of
CLEANBYTE
,DEADDYTE
andFORBIDDENBYTE
internal constants used by debug hooks on Python memory allocators (PyMem_SetupDebugHooks()
function). Byte patterns0xCB
,0xDB
and0xFB
have been replaced with0xCD
,0xDD
and0xFD
to use the same values than Windows CRT debugmalloc()
andfree()
.bpo-36443: Since Python 3.7.0, calling
Py_DecodeLocale()
beforePy_Initialize()
produces mojibake if theLC_CTYPE
locale is coerced and/or if the UTF-8 Mode is enabled by the user configuration. The LC_CTYPE coercion and UTF-8 Mode are now disabled by default to fix the mojibake issue. They must now be enabled explicitly (opt-in) using the new_Py_PreInitialize()
API with_PyPreConfig
.bpo-36025: Fixed an accidental change to the datetime C API where the arguments to the
PyDate_FromTimestamp()
function were incorrectly interpreted as a single timestamp rather than an arguments tuple, which causes existing code to start raisingTypeError
. The backwards-incompatible change was only present in alpha releases of Python 3.8. Patch by Paul Ganssle.bpo-35810: Modify
PyObject_Init
to correctly increase the refcount of heap- allocated Type objects. Also fix the refcounts of the heap-allocated types that were either doing this manually or not decreasing the type’s refcount in tp_dealloc
Python 3.8.0 alpha 3¶
Release date: 2019-03-25
Security¶
bpo-36216: Changes urlsplit() to raise ValueError when the URL contains characters that decompose under IDNA encoding (NFKC-normalization) into characters that affect how the URL is parsed.
bpo-35121: Don’t send cookies of domain A without Domain attribute to domain B when domain A is a suffix match of domain B while using a cookiejar with
http.cookiejar.DefaultCookiePolicy
policy. Patch by Karthikeyan Singaravelan.
Core and Builtins¶
bpo-36421: Fix a possible double decref in _ctypes.c’s
PyCArrayType_new()
.bpo-36412: Fix a possible crash when creating a new dictionary.
bpo-36398: Fix a possible crash in
structseq_repr()
.bpo-36256: Fix bug in parsermodule when parsing a state in a DFA that has two or more arcs with labels of the same type. Patch by Pablo Galindo.
bpo-36365: repr(structseq) is no longer limited to 512 bytes.
bpo-36374: Fix a possible null pointer dereference in
merge_consts_recursive()
. Patch by Zackery Spytz.bpo-36236: At Python initialization, the current directory is no longer prepended to
sys.path
if it has been removed.bpo-36352: Python initialization now fails with an error, rather than silently truncating paths, if a path is too long.
bpo-36301: Python initialization now fails if decoding
pybuilddir.txt
configuration file fails at startup.bpo-36333: Fix leak in _PyRuntimeState_Fini. Contributed by Stéphane Wirtel.
bpo-36332: The builtin
compile()
can now handle AST objects that contain assignment expressions. Patch by Pablo Galindo.bpo-36282: Improved error message for too much positional arguments in some builtin functions.
bpo-30040: New empty dict uses fewer memory for now. It used more memory than empty dict created by
dict.clear()
. And empty dict creation and deletion is about 2x faster. Patch by Inada Naoki.bpo-36262: Fix an unlikely memory leak on conversion from string to float in the function
_Py_dg_strtod()
used byfloat(str)
,complex(str)
,pickle.load()
,marshal.load()
, etc.bpo-36252: Update Unicode databases to version 12.0.0.
bpo-36218: Fix a segfault occurring when sorting a list of heterogeneous values. Patch contributed by Rémi Lapeyre and Elliot Gorokhovsky.
bpo-36188: Cleaned up left-over vestiges of Python 2 unbound method handling in method objects and documentation. Patch by Martijn Pieters
bpo-36124: Add a new interpreter-specific dict and expose it in the C-API via PyInterpreterState_GetDict(). This parallels PyThreadState_GetDict(). However, extension modules should continue using PyModule_GetState() for their own internal per-interpreter state.
bpo-35975: Add a
feature_version
flag toast.parse()
(documented) andcompile()
(hidden) that allows tweaking the parser to support older versions of the grammar. In particular, iffeature_version
is 5 or 6, the hacks for theasync
andawait
keyword from PEP 492 are reinstated. (For 7 or higher, these are unconditionally treated as keywords, but they are still special tokens rather thanNAME
tokens that the parser driver recognizes.)bpo-31904: Use UTF-8 as the system encoding on VxWorks.
bpo-36048: The
__index__()
special method will be used instead of__int__()
for implicit conversion of Python numbers to C integers. Using the__int__()
method in implicit conversions has been deprecated.bpo-35808: Retire pgen and use a modified version of pgen2 to generate the parser. Patch by Pablo Galindo.
Library¶
bpo-36401: The class documentation created by pydoc now has a separate section for readonly properties.
bpo-36320: The typing.NamedTuple() class has deprecated the _field_types attribute in favor of the __annotations__ attribute which carried the same information. Also, both attributes were converted from OrderedDict to a regular dict.
bpo-34745: Fix
asyncio
ssl memory issues caused by circular referencesbpo-36324: Add method to statistics.NormalDist for computing the inverse cumulative normal distribution.
bpo-36321: collections.namedtuple() misspelled the name of an attribute. To be consistent with typing.NamedTuple, the attribute name should have been “_field_defaults” instead of “_fields_defaults”. For backwards compatibility, both spellings are now created. The misspelled version may be removed in the future.
bpo-36297: “unicode_internal” codec is removed. It was deprecated since Python 3.3. Patch by Inada Naoki.
bpo-36298: Raise ModuleNotFoundError in pyclbr when a module can’t be found. Thanks to ‘mental’ for the bug report.
bpo-36268: Switch the default format used for writing tars with mod:
tarfile
to the modern POSIX.1-2001 pax standard, from the vendor-specific GNU. Contributed by C.A.M. Gerlach.bpo-36285: Fix integer overflows in the array module. Patch by Stephan Hohe.
bpo-31904: Add _signal module support for VxWorks.
bpo-36272:
logging
does not silently ignore RecursionError anymore. Patch contributed by Rémi Lapeyre.bpo-36280: Add a kind field to ast.Constant. It is ‘u’ if the literal has a ‘u’ prefix (i.e. a Python 2 style unicode literal), else None.
bpo-35931: The
pdb
debug
command now gracefully handles all exceptions.bpo-36251: Fix format strings used for stderrprinter and re.Match reprs. Patch by Stephan Hohe.
bpo-36235: Fix
CFLAGS
incustomize_compiler()
ofdistutils.sysconfig
: when theCFLAGS
environment variable is defined, don’t overrideCFLAGS
variable with theOPT
variable anymore. Initial patch written by David Malcolm.bpo-35807: Update ensurepip to install pip 19.0.3 and setuptools 40.8.0.
bpo-36179: Fix two unlikely reference leaks in _hashopenssl. The leaks only occur in out-of-memory cases.
bpo-36169: Add overlap() method to statistics.NormalDist. Computes the overlapping coefficient for two normal distributions.
bpo-36103: Default buffer size used by
shutil.copyfileobj()
is changed from 16 KiB to 64 KiB on non-Windows platform to reduce system call overhead. Contributed by Inada Naoki.bpo-36130: Fix
pdb
withskip=...
when stepping into a frame without a__name__
global. Patch by Anthony Sottile.bpo-35652: shutil.copytree(copy_function=…) erroneously pass DirEntry instead of a path string.
bpo-35178: Ensure custom
warnings.formatwarning()
function can receiveline
as positional argument. Based on patch by Tashrif Billah.bpo-36106: Resolve potential name clash with libm’s sinpi(). Patch by Dmitrii Pasechnik.
bpo-36091: Clean up reference to async generator in Lib/types. Patch by Henry Chen.
bpo-36043:
FileCookieJar
supports path-like object. Contributed by Stéphane Wirtelbpo-35899: Enum has been fixed to correctly handle empty strings and strings with non-Latin characters (ie. ‘α’, ‘א’) without crashing. Original patch contributed by Maxwell. Assisted by Stéphane Wirtel.
bpo-21269: Add
args
andkwargs
properties to mock call objects. Contributed by Kumar Akshay.bpo-30670:
pprint.pp
has been added to pretty-print objects with dictionary keys being sorted with their insertion order by default. Parameter sort_dicts has been added topprint.pprint
,pprint.pformat
andpprint.PrettyPrinter
. Contributed by Rémi Lapeyre.bpo-35843: Implement
__getitem__
for_NamespacePath
. Patch by Anthony Sottile.bpo-35802: Clean up code which checked presence of
os.stat
/os.lstat
/os.chmod
which are always present. Patch by Anthony Sottile.bpo-35715: Librates the return value of a ProcessPoolExecutor _process_worker after it’s no longer needed to free memory
bpo-35493: Use
multiprocessing.connection.wait()
instead of polling each 0.2 seconds for worker updates inmultiprocessing.Pool
. Patch by Pablo Galindo.bpo-35661: Store the venv prompt in pyvenv.cfg.
bpo-35121: Don’t set cookie for a request when the request path is a prefix match of the cookie’s path attribute but doesn’t end with “/”. Patch by Karthikeyan Singaravelan.
bpo-21478: Calls to a child function created with
unittest.mock.create_autospec()
should propagate to the parent. Patch by Karthikeyan Singaravelan.bpo-35198: Fix C++ extension compilation on AIX
Documentation¶
bpo-36329: Declare the path of the Python binary for the usage of
Tools/scripts/serve.py
when executingmake -C Doc/ serve
. Contributed by Stéphane Wirtelbpo-36138: Improve documentation about converting datetime.timedelta to scalars.
bpo-21314: A new entry was added to the Core Language Section of the Programming FAQ, which explaines the usage of slash(/) in the signature of a function. Patch by Lysandros Nikolaou
Tests¶
bpo-36234: test_posix.PosixUidGidTests: add tests for invalid uid/gid type (str). Initial patch written by David Malcolm.
bpo-29571: Fix
test_re.test_locale_flag()
: uselocale.getpreferredencoding()
rather thanlocale.getlocale()
to get the locale encoding. With some locales,locale.getlocale()
returns the wrong encoding.bpo-36123: Fix race condition in test_socket.
Build¶
bpo-36356: Fix leaks that led to build failure when configured with address sanitizer.
bpo-36146: Add
TEST_EXTENSIONS
constant tosetup.py
to allow to not build test extensions like_testcapi
.bpo-36146: Fix setup.py on macOS: only add
/usr/include/ffi
to include directories of _ctypes, not for all extensions.bpo-31904: Enable build system to cross-build for VxWorks RTOS.
Windows¶
bpo-36312: Fixed decoders for the following code pages: 50220, 50221, 50222, 50225, 50227, 50229, 57002 through 57011, 65000 and 42.
bpo-36264: Don’t honor POSIX
HOME
inos.path.expanduser
on windows. Patch by Anthony Sottile.bpo-24643: Fix name collisions due to
#define timezone _timezone
in PC/pyconfig.h.
IDLE¶
bpo-36405: Use dict unpacking in idlelib.
bpo-36396: Remove fgBg param of idlelib.config.GetHighlight(). This param was only used twice and changed the return type.
bpo-36176: Fix IDLE autocomplete & calltip popup colors. Prevent conflicts with Linux dark themes (and slightly darken calltip background).
bpo-23205: For the grep module, add tests for findfiles, refactor findfiles to be a module-level function, and refactor findfiles to use os.walk.
bpo-23216: Add docstrings to IDLE search modules.
bpo-36152: Remove colorizer.ColorDelegator.close_when_done and the corresponding argument of .close(). In IDLE, both have always been None or False since 2007.
bpo-32129: Avoid blurry IDLE application icon on macOS with Tk 8.6. Patch by Kevin Walzer.
bpo-36096: Refactor class variables to instance variables in colorizer.
bpo-30348: Increase test coverage of idlelib.autocomplete by 30%. Patch by Louie Lu
Tools/Demos¶
C API¶
Python 3.8.0 alpha 2¶
Release date: 2019-02-25
Core and Builtins¶
bpo-36052: Raise a
SyntaxError
when assigning a value to__debug__
with the Assignment Operator. Contributed by Stéphane Wirtel and Pablo Galindo.bpo-36012: Doubled the speed of class variable writes. When a non-dunder attribute was updated, there was an unnecessary call to update slots.
bpo-35942: The error message emitted when returning invalid types from
__fspath__
in interfaces that allow passingPathLike
objects has been improved and now it does explain the origin of the error.bpo-36016:
gc.get_objects
can now receive an optional parameter indicating a generation to get objects from. Patch by Pablo Galindo.bpo-1054041: When the main interpreter exits due to an uncaught KeyboardInterrupt, the process now exits in the appropriate manner for its parent process to detect that a SIGINT or ^C terminated the process. This allows shells and batch scripts to understand that the user has asked them to stop.
bpo-35992: Fix
__class_getitem__()
not being called on a class with a custom non-subscriptable metaclass.bpo-35993: Fix a crash on fork when using subinterpreters. Contributed by Stéphane Wirtel
bpo-35991: Fix a potential double free in Modules/_randommodule.c.
bpo-35961: Fix a crash in slice_richcompare(): use strong references rather than stolen references for the two temporary internal tuples.
bpo-35911: Enable the creation of cell objects by adding a
cell.__new__
method, and expose the typecell
inLib/types.py
under the name CellType. Patch by Pierre Glaser.bpo-12822: Use monotonic clock for
pthread_cond_timedwait
whenpthread_condattr_setclock
andCLOCK_MONOTONIC
are available.bpo-15248: The compiler emits now syntax warnings in the case when a comma is likely missed before tuple or list.
bpo-35886: The implementation of PyInterpreterState has been moved into the internal header files (guarded by Py_BUILD_CORE).
bpo-31506: Clarify the errors reported when
object.__new__
andobject.__init__
receive more than one argument. Contributed by Sanyam Khurana.bpo-35724: Signal-handling is now guaranteed to happen relative to the main interpreter.
bpo-33608: We added a new internal _Py_AddPendingCall() that operates relative to the provided interpreter. This allows us to use the existing implementation to ask another interpreter to do work that cannot be done in the current interpreter, like decref an object the other interpreter owns. The existing Py_AddPendingCall() only operates relative to the main interpreter.
bpo-33989: Fix a possible crash in
list.sort()
when sorting objects withob_type->tp_richcompare == NULL
. Patch by Zackery Spytz.
Library¶
bpo-35512:
unittest.mock.patch.dict()
used as a decorator with string target resolves the target during function call instead of during decorator construction. Patch by Karthikeyan Singaravelan.bpo-36018: Add statistics.NormalDist, a tool for creating and manipulating normal distributions of random variable. Features a composite class that treats the mean and standard deviation of measurement data as single entity.
bpo-35904: Added statistics.fmean() as a faster, floating point variant of the existing mean() function.
bpo-35918: Removed broken
has_key
method from multiprocessing.managers.SyncManager.dict. Contributed by Rémi Lapeyre.bpo-18283: Add support for bytes to
shutil.which()
.bpo-35960: Fix
dataclasses.field()
throwing away empty mapping objects passed as metadata.bpo-35500: Write expected and actual call parameters on separate lines in
unittest.mock.Mock.assert_called_with()
assertion errors. Contributed by Susan Su.bpo-35931: The
pdb
debug
command now gracefully handles syntax errors.bpo-24209: In http.server script, rely on getaddrinfo to bind to preferred address based on the bind parameter. Now default bind or binding to a name may bind to IPv6 or dual-stack, depending on the environment.
bpo-35321: Set
__spec__.origin
of_frozen_importlib
to frozen so that it matches the behavior of_frozen_importlib_external
. Patch by Nina Zakharenko.bpo-35378: Fix a reference issue inside
multiprocessing.Pool
that caused the pool to remain alive if it was deleted without being closed or terminated explicitly. A new strong reference is added to the pool iterators to link the lifetime of the pool to the lifetime of its iterators so the pool does not get destroyed if a pool iterator is still alive.bpo-34294: re module, fix wrong capturing groups in rare cases.
re.search()
,re.findall()
,re.sub()
and other functions that scan through string looking for a match, should reset capturing groups between two match attempts. Patch by Ma Lin.bpo-35615:
weakref
: Fix a RuntimeError when copying a WeakKeyDictionary or a WeakValueDictionary, due to some keys or values disappearing while iterating.bpo-35606: Implement
math.prod()
as analogous function tosum()
that returns the product of a ‘start’ value (default: 1) times an iterable of numbers. Patch by Pablo Galindo.bpo-32417: Performing arithmetic between
datetime.datetime
subclasses anddatetime.timedelta
now returns an object of the same type as thedatetime.datetime
subclass. As a result,datetime.datetime.astimezone()
and alternate constructors likedatetime.datetime.now()
anddatetime.fromtimestamp()
called with atz
argument now also retain their subclass.bpo-35153: Add headers optional keyword-only parameter to
xmlrpc.client.ServerProxy
,xmlrpc.client.Transport
andxmlrpc.client.SafeTransport
. Patch by Cédric Krier.bpo-34572: Fix C implementation of pickle.loads to use importlib’s locking mechanisms, and thereby avoid using partially-loaded modules. Patch by Tim Burgess.
Documentation¶
Tests¶
bpo-27313: Avoid test_ttk_guionly ComboboxTest failure with macOS Cocoa Tk.
bpo-36019: Add test.support.TEST_HTTP_URL and replace references of http://www.example.com by this new constant. Contributed by Stéphane Wirtel.
bpo-36037: Fix test_ssl for strict OpenSSL configuration like RHEL8 strict crypto policy. Use older TLS version for minimum TLS version of the server SSL context if needed, to test TLS version older than default minimum TLS version.
bpo-35505: Make test_imap4_host_default_value independent on whether the local IMAP server is running.
bpo-35917: multiprocessing: provide unit tests for SyncManager and SharedMemoryManager classes + all the shareable types which are supposed to be supported by them. (patch by Giampaolo Rodola)
bpo-35704: Skip
test_shutil.test_unpack_archive_xztar
to prevent a MemoryError on 32-bit AIX when MAXDATA setting is less than 0x20000000.Patch by Michael Felt (aixtools)
bpo-34720: Assert m_state != NULL to mimic GC traversal functions that do not correctly handle module creation when the module state has not been created.
Windows¶
bpo-35976: Added ARM build support to Windows build files in PCBuild.
bpo-35692:
pathlib
no longer raises when checking file and directory existence on drives that are not readybpo-35872: Uses the base Python executable when invoking venv in a virtual environment
bpo-35873: Prevents venv paths being inherited by child processes
bpo-35299: Fix sysconfig detection of the source directory and distutils handling of pyconfig.h during PGO profiling
IDLE¶
Python 3.8.0 alpha 1¶
Release date: 2019-02-03
Security¶
bpo-35746: [CVE-2019-5010] Fix a NULL pointer deref in ssl module. The cert parser did not handle CRL distribution points with empty DP or URI correctly. A malicious or buggy certificate can result into segfault. Vulnerability (TALOS-2018-0758) reported by Colin Read and Nicolas Edet of Cisco.
bpo-34812: The
-I
command line option (run Python in isolated mode) is now also copied by themultiprocessing
anddistutils
modules when spawning child processes. Previously, only-E
and-s
options (enabled by-I
) were copied.bpo-34791: The xml.sax and xml.dom.domreg no longer use environment variables to override parser implementations when sys.flags.ignore_environment is set by -E or -I arguments.
bpo-17239: The xml.sax and xml.dom.minidom parsers no longer processes external entities by default. External DTD and ENTITY declarations no longer load files or create network connections.
bpo-34623: CVE-2018-14647: The C accelerated _elementtree module now initializes hash randomization salt from _Py_HashSecret instead of libexpat’s default CSPRNG.
bpo-34405: Updated to OpenSSL 1.1.0i for Windows builds.
bpo-33871: Fixed sending the part of the file in
os.sendfile()
on macOS. Using the trailers argument could cause sending more bytes from the input file than was specified.bpo-32533: Fixed thread-safety of error handling in _ssl.
bpo-33136: Harden ssl module against LibreSSL CVE-2018-8970. X509_VERIFY_PARAM_set1_host() is called with an explicit namelen. A new test ensures that NULL bytes are not allowed.
bpo-33001: Minimal fix to prevent buffer overrun in os.symlink on Windows
bpo-32981: Regexes in difflib and poplib were vulnerable to catastrophic backtracking. These regexes formed potential DOS vectors (REDOS). They have been refactored. This resolves CVE-2018-1060 and CVE-2018-1061. Patch by Jamie Davis.
bpo-28414: The ssl module now allows users to perform their own IDN en/decoding when using SNI.
Core and Builtins¶
bpo-35877: Make parenthesis optional for named expressions in while statement. Patch by Karthikeyan Singaravelan.
bpo-35814: Allow same right hand side expressions in annotated assignments as in normal ones. In particular,
x: Tuple[int, int] = 1, 2
(without parentheses on the right) is now allowed.bpo-35766: Add the option to parse PEP 484 type comments in the ast module. (Off by default.) This is merging the key functionality of the third party fork thereof, [typed_ast](https://github.com/python/typed_ast).
bpo-35713: Reorganize Python initialization to get working exceptions and sys.stderr earlier.
bpo-33416: Add end line and end column position information to the Python AST nodes. This is a C-level backwards incompatible change.
bpo-35720: Fixed a minor memory leak in pymain_parse_cmdline_impl function in Modules/main.c
bpo-35634:
func(**kwargs)
will now raise an error whenkwargs
is a mapping containing multiple entries with the same key. An error was already raised when other keyword arguments are passed before**kwargs
since Python 3.6.bpo-35623: Fix a crash when sorting very long lists. Patch by Stephan Hohe.
bpo-35214: clang Memory Sanitizer build instrumentation was added to work around false positives from posix, socket, time, test_io, and test_faulthandler.
bpo-35560: Fix an assertion error in
format()
in debug build for floating point formatting with “n” format, zero padding and small width. Release build is not impacted. Patch by Karthikeyan Singaravelan.bpo-35552: Format characters
%s
and%V
inPyUnicode_FromFormat()
and%s
inPyBytes_FromFormat()
no longer read memory past the limit if precision is specified.bpo-35504: Fix segfaults and
SystemError
s when deleting certain attributes. Patch by Zackery Spytz.bpo-35504: Fixed a SystemError when delete the characters_written attribute of an OSError.
bpo-35494: Improved syntax error messages for unbalanced parentheses in f-string.
bpo-35444: Fixed error handling in pickling methods when fail to look up builtin “getattr”. Sped up pickling iterators.
bpo-35436: Fix various issues with memory allocation error handling. Patch by Zackery Spytz.
bpo-35423: Separate the signal handling trigger in the eval loop from the “pending calls” machinery. There is no semantic change and the difference in performance is insignificant.
bpo-35357: Internal attributes’ names of unittest.mock._Call and unittest.mock.MagicProxy (name, parent & from_kall) are now prefixed with _mock_ in order to prevent clashes with widely used object attributes. Fixed minor typo in test function name.
bpo-35372: Fixed the code page decoder for input longer than 2 GiB containing undecodable bytes.
bpo-35336: Fix PYTHONCOERCECLOCALE=1 environment variable: only coerce the C locale if the LC_CTYPE locale is “C”.
bpo-31241: The lineno and col_offset attributes of AST nodes for list comprehensions, generator expressions and tuples are now point to the opening parenthesis or square brace. For tuples without parenthesis they point to the position of the first item.
bpo-33954: For
str.format()
,float.__format__()
andcomplex.__format__()
methods for non-ASCII decimal point when using the “n” formatter.bpo-35269: Fix a possible segfault involving a newly-created coroutine. Patch by Zackery Spytz.
bpo-35224: Implement PEP 572 (assignment expressions). Patch by Emily Morehouse.
bpo-32492: Speed up
namedtuple
attribute access by 1.6x using a C fast-path for the name descriptors. Patch by Pablo Galindo.bpo-35214: Fixed an out of bounds memory access when parsing a truncated unicode escape sequence at the end of a string such as
'\N'
. It would read one byte beyond the end of the memory allocation.bpo-35214: The interpreter and extension modules have had annotations added so that they work properly under clang’s Memory Sanitizer. A new configure flag –with-memory-sanitizer has been added to make test builds of this nature easier to perform.
bpo-35193: Fix an off by one error in the bytecode peephole optimizer where it could read bytes beyond the end of bounds of an array when removing unreachable code. This bug was present in every release of Python 3.6 and 3.7 until now.
bpo-35169: Improved error messages for forbidden assignments.
bpo-34022: Fix handling of hash-based bytecode files in
zipimport
. Patch by Elvis Pranskevichus.bpo-28401: Debug builds will no longer to attempt to import extension modules built for the ABI as they were never compatible to begin with. Patch by Stefano Rivera.
bpo-29341: Clarify in the docstrings of
os
methods that path-like objects are also accepted as input parameters.bpo-35050:
socket
: Fix off-by-one bug in length check forAF_ALG
name and type.bpo-29743: Raise
ValueError
instead ofOverflowError
in case of a negative_length_
in actypes.Array
subclass. Also raiseTypeError
instead ofAttributeError
for non-integer_length_
. Original patch by Oren Milman.bpo-16806: Fix
lineno
andcol_offset
for multi-line string tokens.bpo-35029:
SyntaxWarning
raised as an exception at code generation time will be now replaced with aSyntaxError
for better error reporting.bpo-34983: Expose
symtable.Symbol.is_nonlocal()
in the symtable module. Patch by Pablo Galindo.bpo-34974:
bytes
andbytearray
constructors no longer convert unexpected exceptions (e.g.MemoryError
andKeyboardInterrupt
) toTypeError
.bpo-34939: Allow annotated names in module namespace that are declared global before the annotation happens. Patch by Pablo Galindo.
bpo-34973: Fixed crash in
bytes()
when thelist
argument is mutated while it is iterated.bpo-34876: The lineno and col_offset attributes of the AST for decorated function and class refer now to the position of the corresponding
def
,async def
andclass
instead of the position of the first decorator. This leads to more correct line reporting in tracing. This is the only case when the position of child AST nodes can precede the position of the parent AST node.bpo-34879: Fix a possible null pointer dereference in bytesobject.c. Patch by Zackery Spytz.
bpo-34784: Fix the implementation of PyStructSequence_NewType in order to create heap allocated StructSequences.
bpo-32912: A
SyntaxWarning
is now emitted instead of aDeprecationWarning
for invalid escape sequences in string and bytes literals.bpo-34854: Fixed a crash in compiling string annotations containing a lambda with a keyword-only argument that doesn’t have a default value.
bpo-34850: The compiler now produces a
SyntaxWarning
when identity checks (is
andis not
) are used with certain types of literals (e.g. strings, ints). These can often work by accident in CPython, but are not guaranteed by the language spec. The warning advises users to use equality tests (==
and!=
) instead.bpo-34824: Fix a possible null pointer dereference in Modules/_ssl.c. Patch by Zackery Spytz.
bpo-30156: The C function
property_descr_get()
uses a “cached” tuple to optimize function calls. But this tuple can be discovered in debug mode withsys.getobjects()
. Remove the optimization, it’s not really worth it and it causes 3 different crashes last years.bpo-34762: Fix contextvars C API to use PyObject* pointer types.
bpo-34751: The hash function for tuples is now based on xxHash which gives better collision results on (formerly) pathological cases. Additionally, on 64-bit systems it improves tuple hashes in general. Patch by Jeroen Demeyer with substantial contributions by Tim Peters.
bpo-34735: Fix a memory leak in Modules/timemodule.c. Patch by Zackery Spytz.
bpo-34683: Fixed a bug where some SyntaxError error pointed to locations that were off-by-one.
bpo-34651: Only allow the main interpreter to fork. The avoids the possibility of affecting the main interpreter, which is critical to operation of the runtime.
bpo-34653: Remove unused function PyParser_SimpleParseStringFilename.
bpo-32236: Warn that line buffering is not supported if
open()
is called with binary mode andbuffering=1
.bpo-34641: Further restrict the syntax of the left-hand side of keyword arguments in function calls. In particular,
f((keyword)=arg)
is now disallowed.bpo-34637: Make the start argument to sum() visible as a keyword argument.
bpo-1621: Do not assume signed integer overflow behavior (C undefined behavior) when performing set hash table resizing.
bpo-34588: Fix an off-by-one in the recursive call pruning feature of traceback formatting.
bpo-34485: On Windows, the LC_CTYPE is now set to the user preferred locale at startup. Previously, the LC_CTYPE locale was “C” at startup, but changed when calling setlocale(LC_CTYPE, “”) or setlocale(LC_ALL, “”).
bpo-34485: Standard streams like sys.stdout now use the “surrogateescape” error handler, instead of “strict”, on the POSIX locale (when the C locale is not coerced and the UTF-8 Mode is disabled).
bpo-34485: Fix the error handler of standard streams like sys.stdout: PYTHONIOENCODING=”:” is now ignored instead of setting the error handler to “strict”.
bpo-34485: Python now gets the locale encoding with C code to initialize the encoding of standard streams like sys.stdout. Moreover, the encoding is now initialized to the Python codec name to get a normalized encoding name and to ensure that the codec is loaded. The change avoids importing _bootlocale and _locale modules at startup by default.
bpo-34527: On FreeBSD, Py_DecodeLocale() and Py_EncodeLocale() now also forces the ASCII encoding if the LC_CTYPE locale is “POSIX”, not only if the LC_CTYPE locale is “C”.
bpo-34527: The UTF-8 Mode is now also enabled by the “POSIX” locale, not only by the “C” locale.
bpo-34403: On HP-UX with C or POSIX locale, sys.getfilesystemencoding() now returns “ascii” instead of “roman8” (when the UTF-8 Mode is disabled and the C locale is not coerced).
bpo-34523: The Python filesystem encoding is now read earlier during the Python initialization.
bpo-12458: Tracebacks show now correct line number for subexpressions in multiline expressions. Tracebacks show now the line number of the first line for multiline expressions instead of the line number of the last subexpression.
bpo-34408: Prevent a null pointer dereference and resource leakage in
PyInterpreterState_New()
.bpo-34400: Fix undefined behavior in parsetok.c. Patch by Zackery Spytz.
bpo-33073: Added as_integer_ratio to ints to make them more interoperable with floats.
bpo-34377: Update valgrind suppression list to use
_PyObject_Free
/_PyObject_Realloc
instead ofPyObject_Free
/PyObject_Realloc
.bpo-34353: Added the “socket” option in the
stat.filemode()
Python implementation to match the C implementation.bpo-34320: Fix
dict(od)
didn’t copy iteration order of OrderedDict.bpo-34113: Fixed crash on debug builds when opcode stack was adjusted with negative numbers. Patch by Constantin Petrisor.
bpo-34100: Compiler now merges constants in tuples and frozensets recursively. Code attributes like
co_names
are merged too.bpo-34151: Performance of list concatenation, repetition and slicing operations is slightly improved. Patch by Sergey Fedoseev.
bpo-34170: -X dev: it is now possible to override the memory allocator using PYTHONMALLOC even if the developer mode is enabled.
bpo-33237: Improved
AttributeError
message for partially initialized module.bpo-34149: Fix min and max functions to get default behavior when key is None.
bpo-34125: Profiling of unbound built-in methods now works when
**kwargs
is given.bpo-34141: Optimized pickling atomic types (None, bool, int, float, bytes, str).
bpo-34126: Fix crashes when profiling certain invalid calls of unbound methods. Patch by Jeroen Demeyer.
bpo-24618: Fixed reading invalid memory when create the code object with too small varnames tuple or too large argument counts.
bpo-34068: In
io.IOBase.close()
, ensure that theclosed
attribute is not set with a live exception. Patch by Zackery Spytz and Serhiy Storchaka.bpo-34087: Fix buffer overflow while converting unicode to numeric values.
bpo-34080: Fixed a memory leak in the compiler when it raised some uncommon errors during tokenizing.
bpo-34066: Disabled interruption by Ctrl-C between calling
open()
and entering a with block inwith open()
.bpo-34042: Fix dict.copy() to maintain correct total refcount (as reported by sys.gettotalrefcount()).
bpo-33418: Fix potential memory leak in function object when it creates reference cycle.
bpo-33985: Implement contextvars.ContextVar.name attribute.
bpo-33956: Update vendored Expat library copy to version 2.2.5.
bpo-24596: Decref the module object in
PyRun_SimpleFileExFlags()
before callingPyErr_Print()
. Patch by Zackery Spytz.bpo-33451: Close directly executed pyc files before calling
PyEval_EvalCode()
.bpo-1617161: The hash of
BuiltinMethodType
instances (methods of built-in classes) now depends on the hash of the identity of __self__ instead of its value. The hash and equality ofModuleType
andMethodWrapperType
instances (methods of user-defined classes and some methods of built-in classes likestr.__add__
) now depend on the hash and equality of the identity of __self__ instead of its value.MethodWrapperType
instances no longer support ordering.bpo-33824: Fix “LC_ALL=C python3.7 -V”: reset properly the command line parser when the encoding changes after reading the Python configuration.
bpo-33803: Fix a crash in hamt.c caused by enabling GC tracking for an object that hadn’t all of its fields set to NULL.
bpo-33738: Seven macro incompatibilities with the Limited API were fixed, and the macros
PyIter_Check()
,PyIndex_Check()
andPyExceptionClass_Name()
were added as functions. A script for automatic macro checks was added.bpo-33786: Fix asynchronous generators to handle GeneratorExit in athrow() correctly
bpo-30167:
PyRun_SimpleFileExFlags
removes__cached__
from module in addition to__file__
.bpo-33706: Fix a crash in Python initialization when parsing the command line options. Thanks Christoph Gohlke for the bug report and the fix!
bpo-33597: Reduce
PyGC_Head
size from 3 words to 2 words.bpo-30654: Fixed reset of the SIGINT handler to SIG_DFL on interpreter shutdown even when there was a custom handler set previously. Patch by Philipp Kerling.
bpo-33622: Fixed a leak when the garbage collector fails to add an object with the
__del__
method or referenced by it into thegc.garbage
list.PyGC_Collect()
can now be called when an exception is set and preserves it.bpo-33462: Make dict and dict views reversible. Patch by Rémi Lapeyre.
bpo-23722: A
RuntimeError
is now raised when the custom metaclass doesn’t provide the__classcell__
entry in the namespace passed totype.__new__
. ADeprecationWarning
was emitted in Python 3.6–3.7.bpo-33499: Add
PYTHONPYCACHEPREFIX
environment variable and-X
pycache_prefix
command-line option to set an alternate root directory for writing module bytecode cache files.bpo-25711: The
zipimport
module has been rewritten in pure Python.bpo-33509: Fix module_globals parameter of warnings.warn_explicit(): don’t crash if module_globals is not a dict.
bpo-31849: Fix signed/unsigned comparison warning in pyhash.c.
bpo-33475: Fixed miscellaneous bugs in converting annotations to strings and optimized parentheses in the string representation.
bpo-20104: Added support for the
setpgroup
,resetids
,setsigmask
,setsigdef
andscheduler
parameters ofposix_spawn
. Patch by Pablo Galindo.bpo-33391: Fix a leak in set_symmetric_difference().
bpo-33363: Raise a SyntaxError for
async with
andasync for
statements outside of async functions.bpo-28055: Fix unaligned accesses in siphash24(). Patch by Rolf Eike Beer.
bpo-33128: Fix a bug that causes PathFinder to appear twice on sys.meta_path. Patch by Pablo Galindo Salgado.
bpo-33331: Modules imported last are now cleared first at interpreter shutdown.
bpo-33312: Fixed clang ubsan (undefined behavior sanitizer) warnings in dictobject.c by adjusting how the internal struct _dictkeysobject shared keys structure is declared.
bpo-33305: Improved syntax error messages for invalid numerical literals.
bpo-33306: Improved syntax error messages for unbalanced parentheses.
bpo-33234: The list constructor will pre-size and not over-allocate when the input length is known.
bpo-33270: Intern the names for all anonymous code objects. Patch by Zackery Spytz.
bpo-30455: The C and Python code and the documentation related to tokens are now generated from a single source file
Grammar/Tokens
.bpo-33176: Add a
toreadonly()
method to memoryviews.bpo-33231: Fix potential memory leak in
normalizestring()
.bpo-33205: Change dict growth function from
round_up_to_power_2(used*2+hashtable_size/2)
toround_up_to_power_2(used*3)
. Previously, dict is shrinked only whenused == 0
. Now dict has more chance to be shrinked.bpo-29922: Improved error messages in ‘async with’ when
__aenter__()
or__aexit__()
return non-awaitable object.bpo-33199: Fix
ma_version_tag
in dict implementation is uninitialized when copying from key-sharing dict.bpo-33053: When using the -m switch, sys.path[0] is now explicitly expanded as the starting working directory, rather than being left as the empty path (which allows imports from the current working directory at the time of the import)
bpo-33138: Changed standard error message for non-pickleable and non-copyable types. It now says “cannot pickle” instead of “can’t pickle” or “cannot serialize”.
bpo-33018: Improve consistency of errors raised by
issubclass()
when called with a non-class and an abstract base class as the first and second arguments, respectively. Patch by Josh Bronson.bpo-33083:
math.factorial
no longer accepts arguments that are not int-like. Patch by Pablo Galindo.bpo-33041: Added new opcode
END_ASYNC_FOR
and fixes the following issues:Setting global
StopAsyncIteration
no longer breaksasync for
loops.Jumping into an
async for
loop is now disabled.Jumping out of an
async for
loop no longer corrupts the stack.
bpo-25750: Fix rare Python crash due to bad refcounting in
type_getattro()
if a descriptor deletes itself from the class. Patch by Jeroen Demeyer.bpo-33041: Fixed bytecode generation for “async for” with a complex target. A StopAsyncIteration raised on assigning or unpacking will be now propagated instead of stopping the iteration.
bpo-33026: Fixed jumping out of “with” block by setting f_lineno.
bpo-33005: Fix a crash on fork when using a custom memory allocator (ex: using PYTHONMALLOC env var). _PyGILState_Reinit() and _PyInterpreterState_Enable() now use the default RAW memory allocator to allocate a new interpreters mutex on fork.
bpo-32911: Due to unexpected compatibility issues discovered during downstream beta testing, reverted bpo-29463.
docstring
field is removed from Module, ClassDef, FunctionDef, and AsyncFunctionDef ast nodes which was added in 3.7a1. Docstring expression is restored as a first statement in their body. Based on patch by Inada Naoki.bpo-17288: Prevent jumps from ‘return’ and ‘exception’ trace events.
bpo-32946: Importing names from already imported module with “from … import …” is now 30% faster if the module is not a package.
bpo-32932: Make error message more revealing when there are non-str objects in
__all__
.bpo-32925: Optimized iterating and containing test for literal lists consisting of non-constants:
x in [a, b]
andfor x in [a, b]
. The case of all constant elements already was optimized.bpo-32889: Update Valgrind suppression list to account for the rename of
Py_ADDRESS_IN_RANG
toaddress_in_range
.bpo-32836: Don’t use temporary variables in cases of list/dict/set comprehensions
bpo-31356: Remove the new API added in bpo-31356 (gc.ensure_disabled() context manager).
bpo-32305: For namespace packages, ensure that both
__file__
and__spec__.origin
are set to None.bpo-32303: Make sure
__spec__.loader
matches__loader__
for namespace packages.bpo-32711: Fix the warning messages for Python/ast_unparse.c. Patch by Stéphane Wirtel
bpo-32583: Fix possible crashing in builtin Unicode decoders caused by write out-of-bound errors when using customized decode error handlers.
bpo-32489: A
continue
statement is now allowed in thefinally
clause.bpo-17611: Simplified the interpreter loop by moving the logic of unrolling the stack of blocks into the compiler. The compiler emits now explicit instructions for adjusting the stack of values and calling the cleaning up code for
break
,continue
andreturn
.Removed opcodes
BREAK_LOOP
,CONTINUE_LOOP
,SETUP_LOOP
andSETUP_EXCEPT
. Added new opcodesROT_FOUR
,BEGIN_FINALLY
andCALL_FINALLY
andPOP_FINALLY
. Changed the behavior ofEND_FINALLY
andWITH_CLEANUP_START
.bpo-32285: New function unicodedata.is_normalized, which can check whether a string is in a specific normal form.
bpo-10544: Yield expressions are now disallowed in comprehensions and generator expressions except the expression for the outermost iterable.
bpo-32117: Iterable unpacking is now allowed without parentheses in yield and return statements, e.g.
yield 1, 2, 3, *rest
. Thanks to David Cuthbert for the change and Jordan Chapman for added tests.bpo-31902: Fix the
col_offset
attribute for ast nodesast.AsyncFor
,ast.AsyncFunctionDef
, andast.AsyncWith
. Previously,col_offset
pointed to the keyword afterasync
.bpo-25862: Fix assertion failures in the
tell()
method ofio.TextIOWrapper
. Patch by Zackery Spytz.bpo-21983: Fix a crash in
ctypes.cast()
in case the type argument is a ctypes structured data type. Patch by Eryk Sun and Oren Milman.bpo-31577: Fix a crash in
os.utime()
in case of a bad ns argument. Patch by Oren Milman.bpo-29832: Remove references to ‘getsockaddrarg’ from various socket error messages. Patch by Oren Milman.
Library¶
bpo-35845: Add ‘order’ parameter to memoryview.tobytes().
bpo-35864: The _asdict() method for collections.namedtuple now returns a regular dict instead of an OrderedDict.
bpo-35537: An ExitStack is now used internally within subprocess.POpen to clean up pipe file handles. No behavior change in normal operation. But if closing one handle were ever to cause an exception, the others will now be closed instead of leaked. (patch by Giampaolo Rodola)
bpo-35847: RISC-V needed the CTYPES_PASS_BY_REF_HACK. Fixes ctypes Structure test_pass_by_value.
bpo-35813: Shared memory submodule added to multiprocessing to avoid need for serialization between processes
bpo-35780: Fix lru_cache() errors arising in recursive, reentrant, or multi-threaded code. These errors could result in orphan links and in the cache being trapped in a state with fewer than the specified maximum number of links. Fix handling of negative maxsize which should have been treated as zero. Fix errors in toggling the “full” status flag. Fix misordering of links when errors are encountered. Sync-up the C code and pure Python code for the space saving path in functions with a single positional argument. In this common case, the space overhead of an lru cache entry is reduced by almost half. Fix counting of cache misses. In error cases, the miss count was out of sync with the actual number of times the underlying user function was called.
bpo-35537:
os.posix_spawn()
andos.posix_spawnp()
now have a setsid parameter.bpo-23846:
asyncio.ProactorEventLoop
now catches and logs send errors when the self-pipe is full.bpo-34323:
asyncio
: EnhanceIocpProactor.close()
log: wait 1 second before the first log, then log every second. Log also the number of seconds sinceclose()
was called.bpo-35674: Add a new
os.posix_spawnp()
function. Patch by Joannah Nanjekye.bpo-35733:
ast.Constant(boolean)
no longer an instance ofast.Num
. Patch by Anthony Sottile.bpo-35726: QueueHandler.prepare() now makes a copy of the record before modifying and enqueueing it, to avoid affecting other handlers in the chain.
bpo-35719: Sped up multi-argument
math
functions atan2(), copysign(), remainder() and hypot() by 1.3–2.5 times.bpo-35717: Fix KeyError exception raised when using enums and compile. Patch contributed by Rémi Lapeyre.
bpo-35699: Fixed detection of Visual Studio Build Tools 2017 in distutils
bpo-32710: Fix memory leaks in asyncio ProactorEventLoop on overlapped operation failure.
bpo-35702: The
time.CLOCK_UPTIME_RAW
constant is now available for macOS 10.12.bpo-32710: Fix a memory leak in asyncio in the ProactorEventLoop when
ReadFile()
orWSASend()
overlapped operation fail immediately: release the internal buffer.bpo-35682: Fix
asyncio.ProactorEventLoop.sendfile()
: don’t attempt to set the result of an internal future if it’s already done.bpo-35283: Add a deprecated warning for the
threading.Thread.isAlive()
method. Patch by Dong-hee Na.bpo-35664: Improve operator.itemgetter() performance by 33% with optimized argument handling and with adding a fast path for the common case of a single non-negative integer index into a tuple (which is the typical use case in the standard library).
bpo-35643: Fixed a SyntaxWarning: invalid escape sequence in Modules/_sha3/cleanup.py. Patch by Mickaël Schoentgen.
bpo-35619: Improved support of custom data descriptors in
help()
andpydoc
.bpo-28503: The
crypt
module now internally uses thecrypt_r()
library function instead ofcrypt()
when available.bpo-35614: Fixed help() on metaclasses. Patch by Sanyam Khurana.
bpo-35568: Expose
raise(signum)
asraise_signal
bpo-35588: The floor division and modulo operations and the
divmod()
function onfractions.Fraction
types are 2–4x faster. Patch by Stefan Behnel.bpo-35585: Speed-up building enums by value, e.g. http.HTTPStatus(200).
bpo-30561: random.gammavariate(1.0, beta) now computes the same result as random.expovariate(1.0 / beta). This synchonizes the two algorithms and eliminates some idiosyncrasies in the old implementation. It does however produce a difference stream of random variables than it used to.
bpo-35537: The
subprocess
module can now use theos.posix_spawn()
function in some cases for better performance.bpo-35526: Delaying the ‘joke’ of barry_as_FLUFL.mandatory to Python version 4.0
bpo-35523: Remove
ctypes
callback workaround: no longer create a callback at startup. Avoid SELinux alert onimport ctypes
andimport uuid
.bpo-31784:
uuid.uuid1()
now callstime.time_ns()
rather thanint(time.time() * 1e9)
.bpo-35513:
TextTestRunner
ofunittest.runner
now usestime.perf_counter()
rather thantime.time()
to measure the execution time of a test:time.time()
can go backwards, whereastime.perf_counter()
is monotonic.bpo-35502: Fixed reference leaks in
xml.etree.ElementTree.TreeBuilder
in case of unfinished building of the tree (in particular when an error was raised during parsing XML).bpo-35348: Make
platform.architecture()
parsing offile
command output more reliable: add the-b
option to thefile
command to omit the filename, force the usage of the C locale, and search also the “shared object” pattern.bpo-35491:
multiprocessing
: AddPool.__repr__()
and enhanceBaseProcess.__repr__()
(add pid and parent pid) to ease debugging. Pool state constant values are now strings instead of integers, for exampleRUN
value becomes'RUN'
instead of0
.bpo-35477:
multiprocessing.Pool.__enter__()
now fails if the pool is not running:with pool:
fails if used more than once.bpo-31446: Copy command line that was passed to CreateProcessW since this function can change the content of the input buffer.
bpo-35471: Python 2.4 dropped MacOS 9 support. The macpath module was deprecated in Python 3.7. The module is now removed.
bpo-23057: Unblock Proactor event loop when keyboard interrupt is received on Windows
bpo-35052: Fix xml.dom.minidom cloneNode() on a document with an entity: pass the correct arguments to the user data handler of an entity.
bpo-20239: Allow repeated assignment deletion of
unittest.mock.Mock
attributes. Patch by Pablo Galindo.bpo-17185: Set
__signature__
on mock forinspect
to get signature. Patch by Karthikeyan Singaravelan.bpo-35445: Memory errors during creating posix.environ no longer ignored.
bpo-35415: Validate fileno= argument to socket.socket().
bpo-35424:
multiprocessing.Pool
destructor now emitsResourceWarning
if the pool is still running.bpo-35330: When a
Mock
instance was used to wrap an object, ifside_effect
is used in one of the mocks of it methods, don’t call the original implementation and return the result of using the side effect the same way that it is done with return_value.bpo-35346: Drop Mac OS 9 and Rhapsody support from the
platform
module. Rhapsody last release was in 2000. Mac OS 9 last release was in 2001.bpo-10496:
check_environ()
ofdistutils.utils
now catchesKeyError
on callingpwd.getpwuid()
: don’t create theHOME
environment variable in this case.bpo-10496:
posixpath.expanduser()
now returns the input path unchanged if theHOME
environment variable is not set and the current user has no home directory (if the current user identifier doesn’t exist in the password database). This change fix thesite
module if the current user doesn’t exist in the password database (if the user has no home directory).bpo-35389:
platform.libc_ver()
now usesos.confstr('CS_GNU_LIBC_VERSION')
if available and the executable parameter is not set.bpo-35394: Add empty slots to asyncio abstract protocols.
bpo-35310: Fix a bug in
select.select()
where, in some cases, the file descriptor sequences were returned unmodified after a signal interruption, even though the file descriptors might not be ready yet.select.select()
will now always return empty lists if a timeout has occurred. Patch by Oran Avraham.bpo-35380: Enable TCP_NODELAY on Windows for proactor asyncio event loop.
bpo-35341: Add generic version of
collections.OrderedDict
to thetyping
module. Patch by Ismo Toijala.bpo-35371: Fixed possible crash in
os.utime()
on Windows when pass incorrect arguments.bpo-35346:
platform.uname()
now redirectsstderr
toos.devnull
when running external programs likecmd /c ver
.bpo-35066: Previously, calling the strftime() method on a datetime object with a trailing ‘%’ in the format string would result in an exception. However, this only occurred when the datetime C module was being used; the python implementation did not match this behavior. Datetime is now PEP-399 compliant, and will not throw an exception on a trailing ‘%’.
bpo-35345: The function
platform.popen
has been removed, it was deprecated since Python 3.3: useos.popen()
instead.bpo-35344: On macOS,
platform.platform()
now usesplatform.mac_ver()
, if it returns a non-empty release string, to get the macOS version rather than the darwin version.bpo-35312: Make
lib2to3.pgen2.parse.ParseError
round-trip pickle-able. Patch by Anthony Sottile.bpo-35308: Fix regression in
webbrowser
where default browsers may be preferred over browsers in theBROWSER
environment variable.bpo-24746: Avoid stripping trailing whitespace in doctest fancy diff. Original patch by R. David Murray & Jairo Trad. Enhanced by Sanyam Khurana.
bpo-28604:
locale.localeconv()
now sets temporarily theLC_CTYPE
locale to theLC_MONETARY
locale if the two locales are different and monetary strings are non-ASCII. This temporary change affects other threads.bpo-35277: Update ensurepip to install pip 18.1 and setuptools 40.6.2.
bpo-24209: Adds IPv6 support when invoking http.server directly.
bpo-35226: Recursively check arguments when testing for equality of
unittest.mock.call
objects and add note that tracking of parameters used to create ancestors of mocks inmock_calls
is not possible.bpo-29564: The warnings module now suggests to enable tracemalloc if the source is specified, the tracemalloc module is available, but tracemalloc is not tracing memory allocations.
bpo-35189: Modify the following fnctl function to retry if interrupted by a signal (EINTR): flock, lockf, fnctl
bpo-30064: Use add_done_callback() in sock_* asyncio API to unsubscribe reader/writer early on calcellation.
bpo-35186: Removed the “built with” comment added when
setup.py upload
is used with eitherbdist_rpm
orbdist_dumb
.bpo-35152: Allow sending more than 2 GB at once on a multiprocessing connection on non-Windows systems.
bpo-35062: Fix incorrect parsing of
_io.IncrementalNewlineDecoder
’s translate argument.bpo-35065: Remove
StreamReaderProtocol._untrack_reader
. The call to_untrack_reader
is currently performed too soon, causing the protocol to forget about the reader beforeconnection_lost
can run and feed the EOF to the reader.bpo-34160: ElementTree and minidom now preserve the attribute order specified by the user.
bpo-35079: Improve difflib.SequenceManager.get_matching_blocks doc by adding ‘non-overlapping’ and changing ‘!=’ to ‘<’.
bpo-33710: Deprecated
l*gettext()
functions and methods in thegettext
module. They return encoded bytes instead of Unicode strings and are artifacts from Python 2 times. Also deprecated functions and methods related to setting the charset forl*gettext()
functions and methods.bpo-35017:
socketserver.BaseServer.serve_forever()
now exits immediately if it’sshutdown()
method is called while it is polling for new events.bpo-35024:
importlib
no longer logswrote
redundantly after(created|could not create)
is already logged. Patch by Quentin Agren.bpo-35047:
unittest.mock
now includes mock calls in exception messages ifassert_not_called
,assert_called_once
, orassert_called_once_with
fails. Patch by Petter Strandmark.bpo-31047: Fix
ntpath.abspath
regression where it didn’t remove a trailing separator on Windows. Patch by Tim Graham.bpo-35053: tracemalloc now tries to update the traceback when an object is reused from a “free list” (optimization for faster object creation, used by the builtin list type for example).
bpo-31553: Add the –json-lines option to json.tool. Patch by hongweipeng.
bpo-34794: Fixed a leak in Tkinter when pass the Python wrapper around Tcl_Obj back to Tcl/Tk.
bpo-34909: Enum: fix grandchildren subclassing when parent mixed with concrete data types.
bpo-35022:
unittest.mock.MagicMock
now supports the__fspath__
method (fromos.PathLike
).bpo-35008: Fixed references leaks when call the
__setstate__()
method ofxml.etree.ElementTree.Element
in the C implementation for already initialized element.bpo-23420: Verify the value for the parameter ‘-s’ of the cProfile CLI. Patch by Robert Kuska
bpo-33947: dataclasses now handle recursive reprs without raising RecursionError.
bpo-34890: Make
inspect.iscoroutinefunction()
,inspect.isgeneratorfunction()
andinspect.isasyncgenfunction()
work withfunctools.partial()
. Patch by Pablo Galindo.bpo-34521: Use
socket.CMSG_SPACE()
to calculate ancillary data size instead ofsocket.CMSG_LEN()
inmultiprocessing.reduction.recvfds()
as RFC 3542 requires the use of the former for portable applications.bpo-31522: The
mailbox.mbox.get_string
function from_ parameter can now successfully be set to a non-default value.bpo-34970: Protect tasks weak set manipulation in
asyncio.all_tasks()
bpo-34969: gzip: Add –fast, –best on the gzip CLI, these parameters will be used for the fast compression method (quick) or the best method compress (slower, but smaller file). Also, change the default compression level to 6 (tradeoff).
bpo-16965: The 2to3
execfile
fixer now opens the file with mode'rb'
. Patch by Zackery Spytz.bpo-34966:
pydoc
now supports aliases not only to methods defined in the end class, but also to inherited methods. The docstring is not duplicated for aliases.bpo-34926:
mimetypes.MimeTypes.guess_type()
now accepts path-like object in addition to url strings. Patch by Mayank Asthana.bpo-23831: Add
moveto()
method to thetkinter.Canvas
widget. Patch by Juliette Monsel.bpo-34941: Methods
find()
,findtext()
andfindall()
of theElement
class in thexml.etree.ElementTree
module are now able to find children which are instances ofElement
subclasses.bpo-32680:
smtplib.SMTP
objects now always have asock
attribute presentbpo-34769: Fix for async generators not finalizing when event loop is in debug mode and garbage collector runs in another thread.
bpo-34936: Fix
TclError
intkinter.Spinbox.selection_element()
. Patch by Juliette Monsel.bpo-34829: Add methods
selection_from
,selection_range
,selection_present
andselection_to
to thetkinter.Spinbox
for consistency with thetkinter.Entry
widget. Patch by Juliette Monsel.bpo-34911: Added secure_protocols argument to http.cookiejar.DefaultCookiePolicy to allow for tweaking of protocols and also to add support by default for wss, the secure websocket protocol.
bpo-34922: Fixed integer overflow in the
digest()
andhexdigest()
methods for the SHAKE algorithm in thehashlib
module.bpo-34925: 25% speedup in argument parsing for the functions in the bisect module.
bpo-34900: Fixed
unittest.TestCase.debug()
when used to call test methods with subtests. Patch by Bruno Oliveira.bpo-34844: logging.Formatter enhancement - Ensure styles and fmt matches in logging.Formatter - Added validate method in each format style class: StrFormatStyle, PercentStyle, StringTemplateStyle. - This method is called in the constructor of logging.Formatter class - Also re-raise the KeyError in the format method of each style class, so it would a bit clear that it’s an error with the invalid format fields.
bpo-34897: Adjust test.support.missing_compiler_executable check so that a nominal command name of “” is ignored. Patch by Michael Felt.
bpo-34871: Fix inspect module polluted
sys.modules
when parsing__text_signature__
of callable.bpo-34898: Add
mtime
argument togzip.compress
for reproducible output. Patch by Guo Ci Teo.bpo-28441: On Cygwin and MinGW, ensure that
sys.executable
always includes the full filename in the path, including the.exe
suffix (unless it is a symbolic link).bpo-34866: Adding
max_num_fields
tocgi.FieldStorage
to make DOS attacks harder by limiting the number ofMiniFieldStorage
objects created byFieldStorage
.bpo-34711: http.server ensures it reports HTTPStatus.NOT_FOUND when the local path ends with “/” and is not a directory, even if the underlying OS (e.g. AIX) accepts such paths as a valid file reference. Patch by Michael Felt.
bpo-34872: Fix self-cancellation in C implementation of asyncio.Task
bpo-34849: Don’t log waiting for
selector.select
in asyncio loop iteration. The waiting is pretty normal for any asyncio program, logging its time just adds a noise to logs without any useful information provided.bpo-34022: The
SOURCE_DATE_EPOCH
environment variable no longer overrides the value of the invalidation_mode argument topy_compile.compile()
, and determines its default value instead.bpo-34819: Use a monotonic clock to compute timeouts in
Executor.map()
andas_completed()
, in order to prevent timeouts from deviating when the system clock is adjusted.bpo-34758: Add .wasm -> application/wasm to list of recognized file types and content type headers
bpo-34789:
xml.sax.make_parser()
now accepts any iterable as its parser_list argument. Patch by Andrés Delfino.bpo-34334: In
QueueHandler
, clearexc_text
fromLogRecord
to prevent traceback from being written twice.bpo-34687: On Windows, asyncio now uses ProactorEventLoop, instead of SelectorEventLoop, by default.
bpo-5950: Support reading zip files with archive comments in
zipimport
.bpo-32892: The parser now represents all constants as
ast.Constant
instead of using specific constant AST types (Num
,Str
,Bytes
,NameConstant
andEllipsis
). These classes are considered deprecated and will be removed in future Python versions.bpo-34728: Add deprecation warning when
loop
is used in methods:asyncio.sleep
,asyncio.wait
andasyncio.wait_for
.bpo-34738: ZIP files created by
distutils
will now include entries for directories.bpo-34659: Add an optional initial argument to itertools.accumulate().
bpo-29577: Support multiple mixin classes when creating Enums.
bpo-34670: Add SSLContext.post_handshake_auth and SSLSocket.verify_client_post_handshake for TLS 1.3’s post handshake authentication feature.
bpo-32718: The Activate.ps1 script from venv works with PowerShell Core 6.1 and is now available under all operating systems.
bpo-31177: Fix bug that prevented using
reset_mock
on mock instances with deleted attributesbpo-34672: Add a workaround, so the
'Z'
time.strftime()
specifier on the musl C library can work in some cases.bpo-34666: Implement
asyncio.StreamWriter.awrite
andasyncio.StreamWriter.aclose()
coroutines. Methods are needed for providing a consistent stream API with control flow switched on by default.bpo-6721: Acquire the logging module’s commonly used internal locks while fork()ing to avoid deadlocks in the child process.
bpo-34658: Fix a rare interpreter unhandled exception state SystemError only seen when using subprocess with a preexec_fn while an after_parent handler has been registered with os.register_at_fork and the fork system call fails.
bpo-34652: Ensure
os.lchmod()
is never defined on Linux.bpo-34638: Store a weak reference to stream reader to break strong references loop between reader and protocol. It allows to detect and close the socket if the stream is deleted (garbage collected) without
close()
call.bpo-34536:
Enum._missing_
: raiseValueError
if None returned andTypeError
if non-member is returned.bpo-34636: Speed up re scanning of many non-matching characters for s w and d within bytes objects. (microoptimization)
bpo-24412: Add
addModuleCleanup()
andaddClassCleanup()
to unittest to support cleanups forsetUpModule()
andsetUpClass()
. Patch by Lisa Roach.bpo-34630: Don’t log SSL certificate errors in asyncio code (connection error logging is skipped already).
bpo-32490: Prevent filename duplication in
subprocess
exception messages. Patch by Zackery Spytz.bpo-34363: dataclasses.asdict() and .astuple() now handle namedtuples correctly.
bpo-34625: Update vendorized expat library version to 2.2.6.
bpo-32270: The subprocess module no longer mistakenly closes redirected fds even when they were in pass_fds when outside of the default {0, 1, 2} set.
bpo-34622: Create a dedicated
asyncio.CancelledError
,asyncio.InvalidStateError
andasyncio.TimeoutError
exception classes. Inherit them from corresponding exceptions fromconcurrent.futures
package. Extractasyncio
exceptions into a separate file.bpo-34610: Fixed iterator of
multiprocessing.managers.DictProxy
.bpo-34421: Fix distutils logging for non-ASCII strings. This caused installation issues on Windows.
bpo-34604: Fix possible mojibake in the error message of
pwd.getpwnam
andgrp.getgrnam
using string representation because of invisible characters or trailing whitespaces. Patch by William Grzybowski.bpo-30977: Make uuid.UUID use
__slots__
to reduce its memory footprint. Based on original patch by Wouter Bolsterlee.bpo-34574: OrderedDict iterators are not exhausted during pickling anymore. Patch by Sergey Fedoseev.
bpo-8110: Refactored
subprocess
to check for Windows-specific modules rather thansys.platform == 'win32'
.bpo-34530:
distutils.spawn.find_executable()
now falls back onos.defpath
if thePATH
environment variable is not set.bpo-34563: On Windows, fix multiprocessing.Connection for very large read: fix _winapi.PeekNamedPipe() and _winapi.ReadFile() for read larger than INT_MAX (usually 2^31-1).
bpo-34558: Correct typo in Lib/ctypes/_aix.py
bpo-34282: Move
Enum._convert
toEnumMeta._convert_
and fix enum members getting shadowed by parent attributes.bpo-22872: When the queue is closed,
ValueError
is now raised bymultiprocessing.Queue.put()
andmultiprocessing.Queue.get()
instead ofAssertionError
andOSError
, respectively. Patch by Zackery Spytz.bpo-34515: Fix parsing non-ASCII identifiers in
lib2to3.pgen2.tokenize
(PEP 3131).bpo-13312: Avoids a possible integer underflow (undefined behavior) in the time module’s year handling code when passed a very low negative year value.
bpo-34472: Improved compatibility for streamed files in
zipfile
. Previously an optional signature was not being written and certain ZIP applications were not supported. Patch by Silas Sewell.bpo-34454: Fix the .fromisoformat() methods of datetime types crashing when given unicode with non-UTF-8-encodable code points. Specifically, datetime.fromisoformat() now accepts surrogate unicode code points used as the separator. Report and tests by Alexey Izbyshev, patch by Paul Ganssle.
bpo-6700: Fix inspect.getsourcelines for module level frames/tracebacks. Patch by Vladimir Matveev.
bpo-34171: Running the
trace
module no longer creates thetrace.cover
file.bpo-34441: Fix crash when an
ABC
-derived class with invalid__subclasses__
is passed as the second argument toissubclass()
. Patch by Alexey Izbyshev.bpo-34427: Fix infinite loop in
a.extend(a)
forMutableSequence
subclasses.bpo-34412: Make
signal.strsignal()
work on HP-UX. Patch by Michael Osipov.bpo-20849: shutil.copytree now accepts a new
dirs_exist_ok
keyword argument. Patch by Josh Bronson.bpo-31715: Associate
.mjs
file extension withapplication/javascript
MIME Type.bpo-34384:
os.readlink()
now accepts path-like andbytes
objects on Windows.bpo-22602: The UTF-7 decoder now raises
UnicodeDecodeError
for ill-formed sequences starting with “+” (as specified in RFC 2152). Patch by Zackery Spytz.bpo-2122: The
mmap.flush()
method now returnsNone
on success, raises an exception on error under all platforms.bpo-34341: Appending to the ZIP archive with the ZIP64 extension no longer grows the size of extra fields of existing entries.
bpo-34333: Fix %-formatting in
pathlib.PurePath.with_suffix()
when formatting an error message.bpo-18540: The
imaplib.IMAP4
andimaplib.IMAP4_SSL
classes now resolve to the local host IP correctly when the default value of host parameter (''
) is used.bpo-26502: Implement
traceback.FrameSummary.__len__()
method to preserve compatibility with the old tuple API.bpo-34318:
assertRaises()
,assertRaisesRegex()
,assertWarns()
andassertWarnsRegex()
no longer success if the passed callable is None. They no longer ignore unknown keyword arguments in the context manager mode. A DeprecationWarning was raised in these cases since Python 3.5.bpo-9372: Deprecate
__getitem__()
methods ofxml.dom.pulldom.DOMEventStream
,wsgiref.util.FileWrapper
andfileinput.FileInput
.bpo-33613: Fix a race condition in
multiprocessing.semaphore_tracker
when the tracker receives SIGINT before it can register signal handlers for ignoring it.bpo-34248: Report filename in the exception raised when the database file cannot be opened by
dbm.gnu.open()
anddbm.ndbm.open()
due to OS-related error. Patch by Zsolt Cserna.bpo-33089: Add math.dist() to compute the Euclidean distance between two points.
bpo-34246:
smtplib.SMTP.send_message()
no longer modifies the content of the mail_options argument. Patch by Pablo S. Blum de Aguiar.bpo-31047: Fix
ntpath.abspath
for invalid paths on windows. Patch by Franz Woellert.bpo-32321: Add pure Python fallback for functools.reduce. Patch by Robert Wright.
bpo-34270: The default asyncio task class now always has a name which can be get or set using two new methods (
get_name()
andset_name()
) and is visible in therepr()
output. An initial name can also be set using the newname
keyword argument toasyncio.create_task()
or thecreate_task()
method of the event loop. If no initial name is set, the default Task implementation generates a name likeTask-1
using a monotonic counter.bpo-34263: asyncio’s event loop will not pass timeouts longer than one day to epoll/select etc.
bpo-34035: Fix several AttributeError in zipfile seek() methods. Patch by Mickaël Schoentgen.
bpo-32215: Fix performance regression in
sqlite3
when a DML statement appeared in a different line than the rest of the SQL query.bpo-34075: Deprecate passing non-ThreadPoolExecutor instances to
AbstractEventLoop.set_default_executor()
.bpo-34251: Restore
msilib.Win64
to preserve backwards compatibility since it’s already used bydistutils
’bdist_msi
command.bpo-19891: Ignore errors caused by missing / non-writable homedir while writing history during exit of an interactive session. Patch by Anthony Sottile.
bpo-33089: Enhanced math.hypot() to support more than two dimensions.
bpo-34228: tracemalloc: PYTHONTRACEMALLOC=0 environment variable and -X tracemalloc=0 command line option are now allowed to disable explicitly tracemalloc at startup.
bpo-13041: Use
shutil.get_terminal_size()
to calculate the terminal width correctly in theargparse.HelpFormatter
class. Initial patch by Zbyszek Jędrzejewski-Szmek.bpo-34213: Allow frozen dataclasses to have a field named “object”. Previously this conflicted with an internal use of “object”.
bpo-34052:
sqlite3.Connection.create_aggregate()
,sqlite3.Connection.create_function()
,sqlite3.Connection.set_authorizer()
,sqlite3.Connection.set_progress_handler()
methods raises TypeError when unhashable objects are passed as callable. These methods now don’t pass such objects to SQLite API. Previous behavior could lead to segfaults. Patch by Sergey Fedoseev.bpo-34197: Attributes skipinitialspace, doublequote and strict of the dialect attribute of the
csv
reader are nowbool
instances instead of integers 0 or 1.bpo-32788: Errors other than
TypeError
raised in methods__adapt__()
and__conform__()
in thesqlite3
module are now propagated to the user.bpo-21446: The
reload
fixer now usesimportlib.reload()
instead of deprecatedimp.reload()
.bpo-940286: pydoc’s
Helper.showtopic()
method now prints the cross references of a topic correctly.bpo-34164:
base64.b32decode()
could raise UnboundLocalError or OverflowError for incorrect padding. Now it always raisesbase64.Error
in these cases.bpo-34097: ZipFile can zip files older than 1980-01-01 and newer than 2107-12-31 using a new
strict_timestamps
parameter at the cost of setting the timestamp to the limit.bpo-34108: Remove extraneous CR in 2to3 refactor.
bpo-34070: Make sure to only check if the handle is a tty, when opening a file with
buffering=-1
.bpo-27494: Reverted bpo-27494. 2to3 rejects now a trailing comma in generator expressions.
bpo-33967: functools.singledispatch now raises TypeError instead of IndexError when no positional arguments are passed.
bpo-34041: Add the parameter deterministic to the
sqlite3.Connection.create_function()
method. Patch by Sergey Fedoseev.bpo-34056: Ensure the loader shim created by
imp.load_module
always returns bytes from itsget_data()
function. This fixes usingimp.load_module
with PEP 552 hash-based pycs.bpo-34054: The multiprocessing module now uses the monotonic clock
time.monotonic()
instead of the system clocktime.time()
to implement timeout.bpo-34043: Optimize tarfile uncompress performance about 15% when gzip is used.
bpo-34044:
subprocess.Popen
now copies the startupinfo argument to leave it unchanged: it will modify the copy, so that the sameSTARTUPINFO
object can be used multiple times.bpo-34010: Fixed a performance regression for reading streams with tarfile. The buffered read should use a list, instead of appending to a bytes object.
bpo-34019: webbrowser: Correct the arguments passed to Opera Browser when opening a new URL using the
webbrowser
module. Patch by Bumsik Kim.bpo-34003: csv.DictReader now creates dicts instead of OrderedDicts. Patch by Michael Selik.
bpo-33978: Closed existing logging handlers before reconfiguration via fileConfig and dictConfig. Patch by Karthikeyan Singaravelan.
bpo-14117: Make minor tweaks to turtledemo. The ‘wikipedia’ example is now ‘rosette’, describing what it draws. The ‘penrose’ print output is reduced. The’1024’ output of ‘tree’ is eliminated.
bpo-33974: Fixed passing lists and tuples of strings containing special characters
"
,\
,{
,}
and\n
as options tottk
widgets.bpo-27500: Fix getaddrinfo to resolve IPv6 addresses correctly.
bpo-24567: Improve random.choices() to handle subnormal input weights that could occasionally trigger an IndexError.
bpo-33871: Fixed integer overflow in
os.readv()
,os.writev()
,os.preadv()
andos.pwritev()
and inos.sendfile()
with headers or trailers arguments (on BSD-based OSes and macOS).bpo-25007: Add
copy.copy()
andcopy.deepcopy()
support to zlib compressors and decompressors. Patch by Zackery Spytz.bpo-33929: multiprocessing: Fix a race condition in Popen of multiprocessing.popen_spawn_win32. The child process now duplicates the read end of pipe instead of “stealing” it. Previously, the read end of pipe was “stolen” by the child process, but it leaked a handle if the child process had been terminated before it could steal the handle from the parent process.
bpo-33899: Tokenize module now implicitly emits a NEWLINE when provided with input that does not have a trailing new line. This behavior now matches what the C tokenizer does internally. Contributed by Ammar Askar.
bpo-33897: Added a ‘force’ keyword argument to logging.basicConfig().
bpo-33695:
shutil.copytree()
usesos.scandir()
function and all copy functions depending from it use cachedos.stat()
values. The speedup for copying a directory with 8000 files is around +9% on Linux, +20% on Windows and + 30% on a Windows SMB share. Also the number ofos.stat()
syscalls is reduced by 38% makingshutil.copytree()
especially faster on network filesystems. (Contributed by Giampaolo Rodola’ in bpo-33695.)bpo-33916: bz2 and lzma: When Decompressor.__init__() is called twice, free the old lock to not leak memory.
bpo-32568: Make select.epoll() and its documentation consistent regarding sizehint and flags.
bpo-33833: Fixed bug in asyncio where ProactorSocketTransport logs AssertionError if force closed during write.
bpo-33663: Convert content length to string before putting to header.
bpo-33721:
os.path
functions that return a boolean result likeexists()
,lexists()
,isdir()
,isfile()
,islink()
, andismount()
, andpathlib.Path
methods that return a boolean result likeexists()
,is_dir()
,is_file()
,is_mount()
,is_symlink()
,is_block_device()
,is_char_device()
,is_fifo()
,is_socket()
now returnFalse
instead of raisingValueError
or its subclassesUnicodeEncodeError
andUnicodeDecodeError
for paths that contain characters or bytes unrepresentable at the OS level.bpo-26544: Fixed implementation of
platform.libc_ver()
. It almost always returned version ‘2.9’ for glibc.bpo-33843: Remove deprecated
cgi.escape
,cgi.parse_qs
andcgi.parse_qsl
.bpo-33842: Remove
tarfile.filemode
which is deprecated since Python 3.3.bpo-30167: Prevent site.main() exception if PYTHONSTARTUP is set. Patch by Steve Weber.
bpo-33805: Improve error message of dataclasses.replace() when an InitVar is not specified
bpo-33687: Fix the call to
os.chmod()
foruu.decode()
if a mode is given or decoded. Patch by Timo Furrer.bpo-33812: Datetime instance d with non-None tzinfo, but with d.tzinfo.utcoffset(d) returning None is now treated as naive by the astimezone() method.
bpo-32108: In configparser, don’t clear section when it is assigned to itself.
bpo-27397: Make email module properly handle invalid-length base64 strings.
bpo-33578: Implement multibyte encoder/decoder state methods
bpo-30805: Avoid race condition with debug logging
bpo-33476: Fix _header_value_parser.py when address group is missing final ‘;’. Contributed by Enrique Perez-Terron
bpo-33694: asyncio: Fix a race condition causing data loss on pause_reading()/resume_reading() when using the ProactorEventLoop.
bpo-32493: Correct test for
uuid_enc_be
availability inconfigure.ac
. Patch by Michael Felt.bpo-33792: Add asyncio.WindowsSelectorEventLoopPolicy and asyncio.WindowsProactorEventLoopPolicy.
bpo-33274: W3C DOM Level 1 specifies return value of Element.removeAttributeNode() as “The Attr node that was removed.” xml.dom.minidom now complies with this requirement.
bpo-33778: Update
unicodedata
’s database to Unicode version 11.0.0.bpo-33165: Added a stacklevel parameter to logging calls to allow use of wrapper/helper functions for logging APIs.
bpo-33770: improve base64 exception message for encoded inputs of invalid length
bpo-33769: asyncio/start_tls: Fix error message; cancel callbacks in case of an unhandled error; mark SSLTransport as closed if it is aborted.
bpo-33767: The concatenation (
+
) and repetition (*
) sequence operations now raiseTypeError
instead ofSystemError
when performed onmmap.mmap
objects. Patch by Zackery Spytz.bpo-33734: asyncio/ssl: Fix AttributeError, increase default handshake timeout
bpo-31014: Fixed creating a controller for
webbrowser
when a user specifies a path to an entry in the BROWSER environment variable. Based on patch by John Still.bpo-2504: Add gettext.pgettext() and variants.
bpo-33197: Add description property for _ParameterKind
bpo-32751: When cancelling the task due to a timeout,
asyncio.wait_for()
will now wait until the cancellation is complete.bpo-32684: Fix gather to propagate cancellation of itself even with return_exceptions.
bpo-33654: Support protocol type switching in SSLTransport.set_protocol().
bpo-33674: Pause the transport as early as possible to further reduce the risk of data_received() being called before connection_made().
bpo-33671:
shutil.copyfile()
,shutil.copy()
,shutil.copy2()
,shutil.copytree()
andshutil.move()
use platform-specific fast-copy syscalls on Linux and macOS in order to copy the file more efficiently. On Windowsshutil.copyfile()
uses a bigger default buffer size (1 MiB instead of 16 KiB) and amemoryview()
-based variant ofshutil.copyfileobj()
is used. The speedup for copying a 512MiB file is about +26% on Linux, +50% on macOS and +40% on Windows. Also, much less CPU cycles are consumed. (Contributed by Giampaolo Rodola’ in bpo-25427.)bpo-33674: Fix a race condition in SSLProtocol.connection_made() of asyncio.sslproto: start immediately the handshake instead of using call_soon(). Previously, data_received() could be called before the handshake started, causing the handshake to hang or fail.
bpo-31647: Fixed bug where calling write_eof() on a _SelectorSocketTransport after it’s already closed raises AttributeError.
bpo-32610: Make asyncio.all_tasks() return only pending tasks.
bpo-32410: Avoid blocking on file IO in sendfile fallback code
bpo-33469: Fix RuntimeError after closing loop that used run_in_executor
bpo-33672: Fix Task.__repr__ crash with Cython’s bogus coroutines
bpo-33654: Fix transport.set_protocol() to support switching between asyncio.Protocol and asyncio.BufferedProtocol. Fix loop.start_tls() to work with asyncio.BufferedProtocols.
bpo-33652: Pickles of type variables and subscripted generics are now future-proof and compatible with older Python versions.
bpo-32493: Fixed
uuid.uuid1()
on FreeBSD.bpo-33238: Add
InvalidStateError
toconcurrent.futures
.Future.set_result
andFuture.set_exception
now raiseInvalidStateError
if the futures are not pending or running. Patch by Jason Haydaman.bpo-33618: Finalize and document preliminary and experimental TLS 1.3 support with OpenSSL 1.1.1
bpo-33625: Release GIL on
grp.getgrnam
,grp.getgrgid
,pwd.getpwnam
andpwd.getpwuid
if reentrant variants of these functions are available. Patch by William Grzybowski.bpo-33623: Fix possible SIGSGV when asyncio.Future is created in __del__
bpo-11874: Use a better regex when breaking usage into wrappable parts. Avoids bogus assertion errors from custom metavar strings.
bpo-30877: Fixed a bug in the Python implementation of the JSON decoder that prevented the cache of parsed strings from clearing after finishing the decoding. Based on patch by c-fos.
bpo-33604: Remove HMAC default to md5 marked for removal in 3.8 (removal originally planned in 3.6, bump to 3.8 in PR 7062).
bpo-33582: Emit a deprecation warning for inspect.formatargspec
bpo-21145: Add
functools.cached_property
decorator, for computed properties cached for the life of the instance.bpo-33570: Change TLS 1.3 cipher suite settings for compatibility with OpenSSL 1.1.1-pre6 and newer. OpenSSL 1.1.1 will have TLS 1.3 ciphers enabled by default.
bpo-28556: Do not simplify arguments to
typing.Union
. NowUnion[Manager, Employee]
is not simplified toEmployee
at runtime. Such simplification previously caused several bugs and limited possibilities for introspection.bpo-12486:
tokenize.generate_tokens()
is now documented as a public API to tokenize unicode strings. It was previously present but undocumented.bpo-33540: Add a new
block_on_close
class attribute toForkingMixIn
andThreadingMixIn
classes ofsocketserver
.bpo-33548: tempfile._candidate_tempdir_list should consider common TEMP locations
bpo-33109: argparse subparsers are once again not required by default, reverting the change in behavior introduced by bpo-26510 in 3.7.0a2.
bpo-33541: Remove unused private method
_strptime.LocaleTime.__pad
(a.k.a._LocaleTime__pad
).bpo-33536: dataclasses.make_dataclass now checks for invalid field names and duplicate fields. Also, added a check for invalid field specifications.
bpo-33542: Prevent
uuid.get_node
from using a DUID instead of a MAC on Windows. Patch by Zvi Effronbpo-26819: Fix race condition with
ReadTransport.resume_reading
in Windows proactor event loop.Fix failure in
typing.get_type_hints()
when ClassVar was provided as a string forward reference.bpo-33516:
unittest.mock.MagicMock
now supports the__round__
magic method.bpo-28612: Added support for Site Maps to urllib’s
RobotFileParser
asRobotFileParser.site_maps()
. Patch by Lady Red, based on patch by Peter Wirtz.bpo-28167: Remove platform.linux_distribution, which was deprecated since 3.5.
bpo-33504: Switch the default dictionary implementation for
configparser
fromcollections.OrderedDict
to the standarddict
type.bpo-33505: Optimize asyncio.ensure_future() by reordering if checks: 1.17x faster.
bpo-33497: Add errors param to cgi.parse_multipart and make an encoding in FieldStorage use the given errors (needed for Twisted). Patch by Amber Brown.
bpo-29235: The
cProfile.Profile
class can now be used as a context manager. Patch by Scott Sanderson.bpo-33495: Change dataclasses.Fields repr to use the repr of each of its members, instead of str. This makes it more clear what each field actually represents. This is especially true for the ‘type’ member.
bpo-26103: Correct
inspect.isdatadescriptor
to look for__set__
or__delete__
. Patch by Aaron Hall.bpo-29209: Removed the
doctype()
method and the html parameter of the constructor ofXMLParser
. Thedoctype()
method defined in a subclass will no longer be called. Deprecated methodsgetchildren()
andgetiterator()
in theElementTree
module emit now aDeprecationWarning
instead ofPendingDeprecationWarning
.bpo-33453: Fix dataclasses to work if using literal string type annotations or if using PEP 563 “Postponed Evaluation of Annotations”. Only specific string prefixes are detected for both ClassVar (“ClassVar” and “typing.ClassVar”) and InitVar (“InitVar” and “dataclasses.InitVar”).
bpo-28556: Minor fixes in typing module: add annotations to
NamedTuple.__new__
, pass*args
and**kwds
inGeneric.__new__
. Original PRs by Paulius Šarka and Chad Dombrova.bpo-33365: Print the header values besides the header keys instead just the header keys if debuglevel is set to >0 in
http.client
. Patch by Marco Strigl.bpo-20087: Updated alias mapping with glibc 2.27 supported locales.
bpo-33422: Fix trailing quotation marks getting deleted when looking up byte/string literals on pydoc. Patch by Andrés Delfino.
bpo-28167: The function
platform.linux_distribution
andplatform.dist
now trigger aDeprecationWarning
and have been marked for removal in Python 3.8bpo-33281: Fix ctypes.util.find_library regression on macOS.
bpo-33311: Text and html output generated by cgitb does not display parentheses if the current call is done directly in the module. Patch by Stéphane Blondon.
bpo-27300: The file classes in tempfile now accept an errors parameter that complements the already existing encoding. Patch by Stephan Hohe.
bpo-32933:
unittest.mock.mock_open()
now supports iteration over the file contents. Patch by Tony Flury.bpo-33217: Raise
TypeError
when looking up non-Enum objects in Enum classes and Enum members.bpo-33197: Update error message when constructing invalid inspect.Parameters Patch by Dong-hee Na.
bpo-33383: Fixed crash in the get() method of the
dbm.ndbm
database object when it is called with a single argument.bpo-33375: The warnings module now finds the Python file associated with a warning from the code object, rather than the frame’s global namespace. This is consistent with how tracebacks and pdb find filenames, and should work better for dynamically executed code.
bpo-33336:
imaplib
now allowsMOVE
command inIMAP4.uid()
(RFC 6851: IMAP MOVE Extension) and potentially as a name of supported method ofIMAP4
object.bpo-32455: Added jump parameter to
dis.stack_effect()
.bpo-27485: Rename and deprecate undocumented functions in
urllib.parse()
.bpo-33332: Add
signal.valid_signals()
to expose the POSIX sigfillset() functionality.bpo-33251:
ConfigParser.items()
was fixed so that key-value pairs passed in viavars
are not included in the resulting output.bpo-33329: Fix multiprocessing regression on newer glibcs
bpo-33334:
dis.stack_effect()
now supports all defined opcodes including NOP and EXTENDED_ARG.bpo-991266: Fix quoting of the
Comment
attribute ofhttp.cookies.SimpleCookie
.bpo-33131: Upgrade bundled version of pip to 10.0.1.
bpo-33308: Fixed a crash in the
parser
module when converting an ST object to a tree of tuples or lists withline_info=False
andcol_info=True
.bpo-23403: lib2to3 now uses pickle protocol 4 for pre-computed grammars.
bpo-33266: lib2to3 now recognizes
rf'...'
strings.bpo-11594: Ensure line-endings are respected when using lib2to3.
bpo-33254: Have
importlib.resources.contents()
andimportlib.abc.ResourceReader.contents()
return an iterable instead of an iterator.bpo-33265:
contextlib.ExitStack
andcontextlib.AsyncExitStack
now use a method instead of a wrapper function for exit callbacks.bpo-33263: Fix FD leak in
_SelectorSocketTransport
Patch by Vlad Starostin.bpo-33256: Fix display of
<module>
call in the html produced bycgitb.html()
. Patch by Stéphane Blondon.bpo-33144:
random.Random()
and its subclassing mechanism got optimized to check only once at class/subclass instantiation time whether itsgetrandbits()
method can be relied on by other methods, includingrandrange()
, for the generation of arbitrarily large random integers. Patch by Wolfgang Maier.bpo-33185: Fixed regression when running pydoc with the
-m
switch. (The regression was introduced in 3.7.0b3 by the resolution of bpo-33053)This fix also changed pydoc to add
os.getcwd()
tosys.path
when necessary, rather than adding"."
.bpo-29613: Added support for the
SameSite
cookie flag to thehttp.cookies
module.bpo-33169: Delete entries of
None
insys.path_importer_cache
whenimportlib.machinery.invalidate_caches()
is called.bpo-33203:
random.Random.choice()
now raisesIndexError
for empty sequences consistently even when called from subclasses without agetrandbits()
implementation.bpo-33224: Update difflib.mdiff() for PEP 479. Convert an uncaught StopIteration in a generator into a return-statement.
bpo-33209: End framing at the end of C implementation of
pickle.Pickler.dump()
.bpo-32861: The urllib.robotparser’s
__str__
representation now includes wildcard entries and the “Crawl-delay” and “Request-rate” fields. Also removes extra newlines that were being appended to the end of the string. Patch by Michael Lazar.bpo-23403:
DEFAULT_PROTOCOL
inpickle
was bumped to 4. Protocol 4 is described in PEP 3154 and available since Python 3.4. It offers better performance and smaller size compared to protocol 3 introduced in Python 3.0.bpo-20104: Improved error handling and fixed a reference leak in
os.posix_spawn()
.bpo-33106: Deleting a key from a read-only dbm database raises module specific error instead of KeyError.
bpo-33175: In dataclasses, Field.__set_name__ now looks up the __set_name__ special method on the class, not the instance, of the default value.
bpo-32380: Create functools.singledispatchmethod to support generic single dispatch on descriptors and methods.
bpo-33141: Have Field objects pass through __set_name__ to their default values, if they have their own __set_name__.
bpo-33096: Allow ttk.Treeview.insert to insert iid that has a false boolean value. Note iid=0 and iid=False would be same. Patch by Garvit Khatri.
bpo-32873: Treat type variables and special typing forms as immutable by copy and pickle. This fixes several minor issues and inconsistencies, and improves backwards compatibility with Python 3.6.
bpo-33134: When computing dataclass’s __hash__, use the lookup table to contain the function which returns the __hash__ value. This is an improvement over looking up a string, and then testing that string to see what to do.
bpo-33127: The ssl module now compiles with LibreSSL 2.7.1.
bpo-32505: Raise TypeError if a member variable of a dataclass is of type Field, but doesn’t have a type annotation.
bpo-33078: Fix the failure on OSX caused by the tests relying on sem_getvalue
bpo-33116: Add ‘Field’ to dataclasses.__all__.
bpo-32896: Fix an error where subclassing a dataclass with a field that uses a default_factory would generate an incorrect class.
bpo-33100: Dataclasses: If a field has a default value that’s a MemberDescriptorType, then it’s from that field being in __slots__, not an actual default value.
bpo-32953: If a non-dataclass inherits from a frozen dataclass, allow attributes to be added to the derived class. Only attributes from the frozen dataclass cannot be assigned to. Require all dataclasses in a hierarchy to be either all frozen or all non-frozen.
bpo-33097: Raise RuntimeError when
executor.submit
is called during interpreter shutdown.bpo-32968: Modulo and floor division involving Fraction and float should return float.
bpo-33061: Add missing
NoReturn
to__all__
in typing.pybpo-33078: Fix the size handling in multiprocessing.Queue when a pickling error occurs.
bpo-33064: lib2to3 now properly supports trailing commas after
*args
and**kwargs
in function signatures.bpo-33056: FIX properly close leaking fds in concurrent.futures.ProcessPoolExecutor.
bpo-33021: Release the GIL during fstat() calls, avoiding hang of all threads when calling mmap.mmap(), os.urandom(), and random.seed(). Patch by Nir Soffer.
bpo-31804: Avoid failing in multiprocessing.Process if the standard streams are closed or None at exit.
bpo-33034: Providing an explicit error message when casting the port property to anything that is not an integer value using
urlparse()
andurlsplit()
. Patch by Matt Eaton.bpo-30249: Improve struct.unpack_from() exception messages for problems with the buffer size and offset.
bpo-33037: Skip sending/receiving data after SSL transport closing.
bpo-27683: Fix a regression in
ipaddress
that result ofhosts()
is empty when the network is constructed by a tuple containing an integer mask and only 1 bit left for addresses.bpo-22674: Add the strsignal() function in the signal module that returns the system description of the given signal, as returned by strsignal(3).
bpo-32999: Fix C implementation of
ABC.__subclasscheck__(cls, subclass)
crashed whensubclass
is not a type object.bpo-33009: Fix inspect.signature() for single-parameter partialmethods.
bpo-32969: Expose several missing constants in zlib and fix corresponding documentation.
bpo-32056: Improved exceptions raised for invalid number of channels and sample width when read an audio file in modules
aifc
,wave
andsunau
.bpo-32970: Improved disassembly of the MAKE_FUNCTION instruction.
bpo-32844: Fix wrong redirection of a low descriptor (0 or 1) to stderr in subprocess if another low descriptor is closed.
bpo-32960: For dataclasses, disallow inheriting frozen from non-frozen classes, and also disallow inheriting non-frozen from frozen classes. This restriction will be relaxed at a future date.
bpo-32713: Fixed tarfile.itn handling of out-of-bounds float values. Patch by Joffrey Fuhrer.
bpo-32257: The ssl module now contains OP_NO_RENEGOTIATION constant, available with OpenSSL 1.1.0h or 1.1.1.
bpo-32951: Direct instantiation of SSLSocket and SSLObject objects is now prohibited. The constructors were never documented, tested, or designed as public constructors. Users were suppose to use ssl.wrap_socket() or SSLContext.
bpo-32929: Remove the tri-state parameter “hash”, and add the boolean “unsafe_hash”. If unsafe_hash is True, add a __hash__ function, but if a __hash__ exists, raise TypeError. If unsafe_hash is False, add a __hash__ based on the values of eq= and frozen=. The unsafe_hash=False behavior is the same as the old hash=None behavior. unsafe_hash=False is the default, just as hash=None used to be.
bpo-32947: Add OP_ENABLE_MIDDLEBOX_COMPAT and test workaround for TLSv1.3 for future compatibility with OpenSSL 1.1.1.
bpo-32146: Document the interaction between frozen executables and the spawn and forkserver start methods in multiprocessing.
bpo-30622: The ssl module now detects missing NPN support in LibreSSL.
bpo-32922: dbm.open() now encodes filename with the filesystem encoding rather than default encoding.
bpo-32759: Free unused arenas in multiprocessing.heap.
bpo-32859: In
os.dup2
, don’t check every call whether thedup3
syscall exists or not.bpo-32556: nt._getfinalpathname, nt._getvolumepathname and nt._getdiskusage now correctly convert from bytes.
bpo-21060: Rewrite confusing message from setup.py upload from “No dist file created in earlier command” to the more helpful “Must create and upload files in one command”.
bpo-32857: In
tkinter
,after_cancel(None)
now raises aValueError
instead of canceling the first scheduled function. Patch by Cheryl Sabella.bpo-32852: Make sure sys.argv remains as a list when running trace.
bpo-31333:
_abc
module is added. It is a speedup module with C implementations for various functions and methods inabc
. Creating an ABC subclass and callingisinstance
orissubclass
with an ABC subclass are up to 1.5x faster. In addition, this makes Python start-up up to 10% faster.Note that the new implementation hides internal registry and caches, previously accessible via private attributes
_abc_registry
,_abc_cache
, and_abc_negative_cache
. There are three debugging helper methods that can be used instead_dump_registry
,_abc_registry_clear
, and_abc_caches_clear
.bpo-32841: Fixed
asyncio.Condition
issue which silently ignored cancellation after notifying and cancelling a conditional lock. Patch by Bar Harel.bpo-32819: ssl.match_hostname() has been simplified and no longer depends on re and ipaddress module for wildcard and IP addresses. Error reporting for invalid wildcards has been improved.
bpo-19675:
multiprocessing.Pool
no longer leaks processes if its initialization fails.bpo-32394: socket: Remove TCP_FASTOPEN,TCP_KEEPCNT,TCP_KEEPIDLE,TCP_KEEPINTVL flags on older version Windows during run-time.
bpo-31787: Fixed refleaks of
__init__()
methods in various modules. (Contributed by Oren Milman)bpo-30157: Fixed guessing quote and delimiter in csv.Sniffer.sniff() when only the last field is quoted. Patch by Jake Davis.
bpo-30688: Added support of
\N{name}
escapes in regular expressions. Based on patch by Jonathan Eunice.bpo-32792: collections.ChainMap() preserves the order of the underlying mappings.
bpo-32775:
fnmatch.translate()
no longer produces patterns which contain set operations. Sets starting with ‘[’ or containing ‘–’, ‘&&’, ‘~~’ or ‘||’ will be interpreted differently in regular expressions in future versions. Currently they emit warnings. fnmatch.translate() now avoids producing patterns containing such sets by accident.bpo-32622: Implement native fast sendfile for Windows proactor event loop.
bpo-32777: Fix a rare but potential pre-exec child process deadlock in subprocess on POSIX systems when marking file descriptors inheritable on exec in the child process. This bug appears to have been introduced in 3.4.
bpo-32647: The ctypes module used to depend on indirect linking for dlopen. The shared extension is now explicitly linked against libdl on platforms with dl.
bpo-32749: A
dbm.dumb
database opened with flags ‘r’ is now read-only.dbm.dumb.open()
with flags ‘r’ and ‘w’ no longer creates a database if it does not exist.bpo-32741: Implement
asyncio.TimerHandle.when()
method.bpo-32691: Use mod_spec.parent when running modules with pdb
bpo-32734: Fixed
asyncio.Lock()
safety issue which allowed acquiring and locking the same lock multiple times, without it being free. Patch by Bar Harel.bpo-32727: Do not include name field in SMTP envelope from address. Patch by Stéphane Wirtel
bpo-31453: Add TLSVersion constants and SSLContext.maximum_version / minimum_version attributes. The new API wraps OpenSSL 1.1 https://www.openssl.org/docs/man1.1.0/ssl/SSL_CTX_set_min_proto_version.html feature.
bpo-24334: Internal implementation details of ssl module were cleaned up. The SSLSocket has one less layer of indirection. Owner and session information are now handled by the SSLSocket and SSLObject constructor. Channel binding implementation has been simplified.
bpo-31848: Fix the error handling in Aifc_read.initfp() when the SSND chunk is not found. Patch by Zackery Spytz.
bpo-32585: Add Ttk spinbox widget to
tkinter.ttk
. Patch by Alan D Moore.bpo-32512:
profile
CLI accepts-m module_name
as an alternative to script path.bpo-8525: help() on a type now displays builtin subclasses. This is intended primarily to help with notification of more specific exception subclasses.
Patch by Sanyam Khurana.
bpo-31639: http.server now exposes a ThreadingHTTPServer class and uses it when the module is run with
-m
to cope with web browsers pre-opening sockets.bpo-29877: compileall: import ProcessPoolExecutor only when needed, preventing hangs on low resource platforms
bpo-32221: Various functions returning tuple containing IPv6 addresses now omit
%scope
part since the same information is already encoded in scopeid tuple item. Especially this speeds upsocket.recvfrom()
when it receives multicast packet since useless resolving of network interface name is omitted.bpo-32147:
binascii.unhexlify()
is now up to 2 times faster. Patch by Sergey Fedoseev.bpo-30693: The TarFile class now recurses directories in a reproducible way.
bpo-30693: The ZipFile class now recurses directories in a reproducible way.
bpo-31680: Added
curses.ncurses_version
.bpo-31908: Fix output of cover files for
trace
module command-line tool. Previously emitted cover files only when--missing
option was used. Patch by Michael Selik.bpo-31608: Raise a
TypeError
instead of crashing if acollections.deque
subclass returns a non-deque from__new__
. Patch by Oren Milman.bpo-31425: Add support for sockets of the AF_QIPCRTR address family, supported by the Linux kernel. This is used to communicate with services, such as GPS or radio, running on Qualcomm devices. Patch by Bjorn Andersson.
bpo-22005: Implemented unpickling instances of
datetime
,date
andtime
pickled by Python 2.encoding='latin1'
should be used for successful decoding.bpo-27645:
sqlite3.Connection
now exposes abackup
method, if the underlying SQLite library is at version 3.6.11 or higher. Patch by Lele Gaifax.bpo-16865: Support arrays >=2GiB in
ctypes
. Patch by Segev Finer.bpo-31508: Removed support of arguments in
tkinter.ttk.Treeview.selection
. It was deprecated in 3.6. Use specialized methods likeselection_set
for changing the selection.bpo-29456: Fix bugs in hangul normalization: u1176, u11a7 and u11c3
Documentation¶
bpo-21257: Document
http.client.parse_headers()
.bpo-34764: Improve example of iter() with 2nd sentinel argument.
bpo-35564: Explicitly set master_doc variable in conf.py for compliance with Sphinx 2.0
bpo-35511: Specified that profile.Profile class doesn’t not support enable or disable methods. Also, elaborated that Profile object as a context manager is only supported in cProfile module.
bpo-10536: Enhance the gettext docs. Patch by Éric Araujo
bpo-35089: Remove mention of
typing.io
andtyping.re
. Their types should be imported fromtyping
directly.bpo-35038: Fix the documentation about an unexisting
f_restricted
attribute in the frame object. Patch by Stéphane Wirtelbpo-35042: Replace PEP XYZ by the pep role and allow to use the direct links to the PEPs.
bpo-35044: Fix the documentation with the role
exc
for the appropriated exception. Patch by Stéphane Wirtelbpo-35035: Rename documentation for
email.utils
toemail.utils.rst
.bpo-34967: Use app.add_object_type() instead of the deprecated Sphinx function app.description_unit()
bpo-34913: Add documentation about the new command line interface of the gzip module.
bpo-32174: chm document displays non-ASCII charaters properly on some MBCS Windows systems.
bpo-11233: Create availability directive for documentation. Original patch by Georg Brandl.
bpo-34790: Document how passing coroutines to asyncio.wait() can be confusing.
bpo-34552: Make clear that
==
operator sometimes is equivalent tois
. The<
,<=
,>
and>=
operators are only defined where they make sense.bpo-28617: Fixed info in the stdtypes docs concerning the types that support membership tests.
bpo-20177: Migrate datetime.date.fromtimestamp to Argument Clinic. Patch by Tim Hoffmann.
bpo-34065: Fix wrongly written basicConfig documentation markup syntax
bpo-33460: replaced ellipsis with correct error codes in tutorial chapter 3.
bpo-33847: Add ‘@’ operator entry to index.
bpo-33409: Clarified the relationship between PEP 538’s PYTHONCOERCECLOCALE and PEP 540’s PYTHONUTF8 mode.
bpo-33197: Add versionadded tag to the documentation of ParameterKind.description
bpo-17045: Improve the C-API doc for PyTypeObject. This includes adding several quick-reference tables and a lot of missing slot/typedef entries. The existing entries were also cleaned up with a slightly more consistent format.
bpo-33736: Improve the documentation of
asyncio.open_connection()
,asyncio.start_server()
and their UNIX socket counterparts.bpo-23859: Document that
asyncio.wait()
does not cancel its futures on timeout.bpo-33604: Update HMAC md5 default to a DeprecationWarning, bump removal to 3.8.
bpo-33594: Document
getargspec
,from_function
andfrom_builtin
as deprecated in their respective docstring, and include version since deprecation in DeprecationWarning message.bpo-33503: Fix broken pypi link
bpo-33421: Add missing documentation for
typing.AsyncContextManager
.bpo-33487: BZ2file now emit a DeprecationWarning when buffering=None is passed, the deprecation message and documentation also now explicitly state it is deprecated since 3.0.
bpo-33378: Add Korean language switcher for https://docs.python.org/3/
bpo-33276: Clarify that the
__path__
attribute on modules cannot be just any value.bpo-33201: Modernize documentation for writing C extension types.
bpo-33195: Deprecate
Py_UNICODE
usage inc-api/arg
document.Py_UNICODE
related APIs are deprecated since Python 3.3, but it is missed in the document.bpo-33126: Document PyBuffer_ToContiguous().
bpo-27212: Modify documentation for the
islice()
recipe to consume initial values up to the start index.bpo-28247: Update
zipapp
documentation to describe how to make standalone applications.bpo-18802: Documentation changes for ipaddress. Patch by Jon Foster and Berker Peksag.
bpo-27428: Update documentation to clarify that
WindowsRegistryFinder
implementsMetaPathFinder
. (Patch by Himanshu Lakhara)bpo-28124: The ssl module function ssl.wrap_socket() has been de-emphasized and deprecated in favor of the more secure and efficient SSLContext.wrap_socket() method.
bpo-17232: Clarify docs for -O and -OO. Patch by Terry Reedy.
bpo-32436: Add documentation for the contextvars module (PEP 567).
bpo-32800: Update link to w3c doc for xml default namespaces.
bpo-11015: Update
test.support
documentation.bpo-32613: Update the faq/windows.html to use the py command from PEP 397 instead of python.
bpo-8722: Document
__getattr__()
behavior when propertyget()
method raisesAttributeError
.bpo-32614: Modify RE examples in documentation to use raw strings to prevent
DeprecationWarning
and add text to REGEX HOWTO to highlight the deprecation.bpo-20709: Remove the paragraph where we explain that os.utime() does not support a directory as path under Windows. Patch by Jan-Philip Gehrcke
bpo-32722: Remove the bad example in the tutorial of the Generator Expression. Patch by Stéphane Wirtel
bpo-31972: Improve docstrings for
pathlib.PurePath
subclasses.bpo-30607: Use the externalized
python-docs-theme
package when building the documentation.bpo-8243: Add a note about curses.addch and curses.addstr exception behavior when writing outside a window, or pad.
bpo-32337: Update documentation related with
dict
order.bpo-31432: Clarify meaning of CERT_NONE, CERT_OPTIONAL, and CERT_REQUIRED flags for ssl.SSLContext.verify_mode.
Tests¶
bpo-35772: Fix sparse file tests of test_tarfile on ppc64 with the tmpfs filesystem. Fix the function testing if the filesystem supports sparse files: create a file which contains data and “holes”, instead of creating a file which contains no data. tmpfs effective block size is a page size (tmpfs lives in the page cache). RHEL uses 64 KiB pages on aarch64, ppc64, ppc64le, only s390x and x86_64 use 4 KiB pages, whereas the test punch holes of 4 KiB.
bpo-35045: Make ssl tests less strict and also accept TLSv1 as system default. The changes unbreaks test_min_max_version on Fedora 29.
bpo-32710:
test_asyncio/test_sendfile.py
now resets the event loop policy usingtearDownModule()
as done in other tests, to prevent a warning when running tests on Windows.bpo-33717: test.pythoninfo now logs information of all clocks, not only time.time() and time.perf_counter().
bpo-35488: Add a test to pathlib’s Path.match() to verify it does not support glob-style ** recursive pattern matching.
bpo-31731: Fix a race condition in
check_interrupted_write()
of test_io: create directly the thread with SIGALRM signal blocked, rather than blocking the signal later from the thread. Previously, it was possible that the thread gets the signal before the signal is blocked.bpo-35424: Fix test_multiprocessing_main_handling: use
multiprocessing.Pool
with a context manager and then explicitly join the pool.bpo-35519: Rename
test.bisect
module totest.bisect_cmd
to avoid conflict withbisect
module when running directly a test like./python Lib/test/test_xmlrpc.py
.bpo-35513: Replace
time.time()
withtime.monotonic()
in tests to measure time delta.bpo-34279:
test.support.run_unittest()
no longer raiseTestDidNotRun
if the test result contains skipped tests. The exception is now only raised if no test have been run and no test have been skipped.bpo-35412: Add testcase to
test_future4
: check unicode literal.bpo-26704: Added test demonstrating double-patching of an instance method. Patch by Anthony Sottile.
bpo-33725: test_multiprocessing_fork may crash on recent versions of macOS. Until the issue is resolved, skip the test on macOS.
bpo-35352: Modify test_asyncio to use the certificate set from the test directory.
bpo-35317: Fix
mktime()
overflow error intest_email
: runtest_localtime_daylight_true_dst_true()
andtest_localtime_daylight_false_dst_true()
with a specific timezone.bpo-21263: After several reports that test_gdb does not work properly on macOS and since gdb is not shipped by default anymore, test_gdb is now skipped on macOS when LLVM Clang has been used to compile Python. Patch by Lysandros Nikolaou
bpo-34279: regrtest issue a warning when no tests have been executed in a particular test file. Also, a new final result state is issued if no test have been executed across all test files. Patch by Pablo Galindo.
bpo-34962: make docstest in Doc now passes., and is enforced in CI
bpo-23596: Use argparse for the command line of the gzip module. Patch by Antony Lee
bpo-34537: Fix
test_gdb.test_strings()
whenLC_ALL=C
and GDB was compiled with Python 3.6 or earlier.bpo-34587: test_socket: Remove RDSTest.testCongestion(). The test tries to fill the receiver’s socket buffer and expects an error. But the RDS protocol doesn’t require that. Moreover, the Linux implementation of RDS expects that the producer of the messages reduces its rate, it’s not the role of the receiver to trigger an error. The test fails on Fedora 28 by design, so just remove it.
bpo-34661: Fix test_shutil if unzip doesn’t support -t.
bpo-34200: Fixed non-deterministic flakiness of test_pkg by not using the scary test.support.module_cleanup() logic to save and restore sys.modules contents between test cases.
bpo-34569: The experimental PEP 554 data channels now correctly pass negative PyLong objects between subinterpreters on 32-bit systems. Patch by Michael Felt.
bpo-34594: Fix usage of hardcoded
errno
values in the tests.bpo-34579: Fix test_embed for AIX Patch by Michael Felt
bpo-34542: Use 3072 RSA keys and SHA-256 signature for test certs and keys.
bpo-11193: Remove special condition for AIX in
test_subprocess.test_undecodable_env
bpo-34347: Fix
test_utf8_mode.test_cmd_line
for AIXbpo-34490: On AIX with AF_UNIX family sockets getsockname() does not provide ‘sockname’, so skip calls to transport.get_extra_info(‘sockname’)
bpo-34391: Fix ftplib test for TLS 1.3 by reading from data socket.
bpo-11192: Fix
test_socket
on AIX 6.1 and later IPv6 zone id supports only supported by inet_pton6_zone() Switch to runtime-based platform.system() to establish current platform rather than build-time based sys.platform()bpo-34399: Update all RSA keys and DH params to use at least 2048 bits.
bpo-34373: Fix
test_mktime
andtest_pthread_getcpuclickid
tests for AIX Add range checking for_PyTime_localtime
for AIX Patch by Michael Feltbpo-11191: Skip the distutils test ‘test_search_cpp’ when using XLC as compiler patch by aixtools (Michael Felt)
Improved an error message when mock assert_has_calls fails.
bpo-33746: Fix test_unittest when run in verbose mode.
bpo-33901: Fix test_dbm_gnu on macOS with gdbm 1.15: add a larger value to make sure that the file size changes.
bpo-33873: Fix a bug in
regrtest
that caused an extra test to run if –huntrleaks/-R was used. Exit with error in case that invalid parameters are specified to –huntrleaks/-R (at least one warmup run and one repetition must be used).bpo-33562: Check that a global asyncio event loop policy is not left behind by any tests.
bpo-33655: Ignore test_posix_fallocate failures on BSD platforms that might be due to running on ZFS.
bpo-32962: Fixed test_gdb when Python is compiled with flags -mcet -fcf-protection -O0.
bpo-33358: Fix
test_embed.test_pre_initialization_sys_options()
when the interpreter is built with--enable-shared
.bpo-32872: Avoid regrtest compatibility issue with namespace packages.
bpo-32517: Fix failing
test_asyncio
on macOS 10.12.2+ due to transport ofKqueueSelector
loop was not being closed.bpo-32663: Making sure the
SMTPUTF8SimTests
class of tests gets run in test_smtplib.py.bpo-27643: Test_C test case needs “signed short” bitfields, but the IBM XLC compiler (on AIX) does not support this Skip the code and test when AIX and XLC are used
Applicable to Python2-2.7 and later
bpo-19417: Add test_bdb.py.
bpo-31809: Add tests to verify connection with secp ECDH curves.
Build¶
bpo-34691: The _contextvars module is now built into the core Python library on Windows.
bpo-35683: Improved Azure Pipelines build steps and now verifying layouts correctly
bpo-35642: Remove asynciomodule.c from pythoncore.vcxproj
bpo-35550: Fix incorrect Solaris #ifdef checks to look for __sun && __SVR4 instead of sun when compiling.
bpo-35499:
make profile-opt
no longer replacesCFLAGS_NODIST
withCFLAGS
. It now adds profile-guided optimization (PGO) flags toCFLAGS_NODIST
: existingCFLAGS_NODIST
flags are kept.bpo-35257: Avoid leaking the linker flags from Link Time Optimizations (LTO) into distutils when compiling C extensions.
bpo-35351: When building Python with clang and LTO, LTO flags are no longer passed into CFLAGS to build third-party C extensions through distutils.
bpo-35139: Fix a compiler error when statically linking
pyexpat
inModules/Setup
.bpo-35059: PCbuild: Set InlineFunctionExpansion to OnlyExplicitInline (“/Ob1” option) in pyproject.props in Debug mode to expand functions marked as inline. This change should make Python compiled in Debug mode a little bit faster on Windows.
bpo-35011: Restores the use of pyexpatns.h to isolate our embedded copy of the expat C library so that its symbols do not conflict at link or dynamic loading time with an embedding application or other extension modules with their own version of libexpat.
bpo-28015: Have –with-lto works correctly with clang.
bpo-34765: Update the outdated install-sh file to the latest revision from automake v1.16.1
bpo-34585: Check for floating-point byte order in configure.ac using compilation tests instead of executing code, so that these checks work in cross-compiled builds.
bpo-34710: Fixed SSL module build with OpenSSL & pedantic CFLAGS.
bpo-34582: Add JUnit XML output for regression tests and update Azure DevOps builds.
bpo-34081: Make Sphinx warnings as errors in the Docs Makefile.
bpo-34555: Fix for case where it was not possible to have both
HAVE_LINUX_VM_SOCKETS_H
andHAVE_SOCKADDR_ALG
be undefined.bpo-33015: Fix an undefined behaviour in the pthread implementation of
PyThread_start_new_thread()
: add a function wrapper to always returnNULL
.bpo-34245: The Python shared library is now installed with write permission (mode 0755), which is the standard way of installing such libraries.
bpo-34121: Fix detection of C11 atomic support on clang.
bpo-32430: Rename Modules/Setup.dist to Modules/Setup, and remove the necessity to copy the former manually to the latter when updating the local source tree.
bpo-30345: Add -g to LDFLAGS when compiling with LTO to get debug symbols.
bpo-5755: Move
-Wstrict-prototypes
option toCFLAGS_NODIST
fromOPT
. This option emitted annoying warnings when building extension modules written in C++.bpo-33614: Ensures module definition files for the stable ABI on Windows are correctly regenerated.
bpo-33648: The –with-c-locale-warning configuration flag has been removed. It has had no effect for about a year.
bpo-33522: Enable CI builds on Visual Studio Team Services at https://python.visualstudio.com/cpython
bpo-33512: configure’s check for “long double” has been simplified
bpo-33483: C compiler is now correctly detected from the standard environment variables. –without-gcc and –with-icc options have been removed.
bpo-33394: Enable the verbose build for extension modules, when GNU make is passed macros on the command line.
bpo-33393: Update config.guess and config.sub files.
bpo-33377: Add new triplets for mips r6 and riscv variants (used in extension suffixes).
bpo-32232: By default, modules configured in
Modules/Setup
are no longer built with-DPy_BUILD_CORE
. Instead, modules that specifically need that preprocessor definition include it in their individual entries.bpo-33182: The embedding tests can once again be built with clang 6.0
bpo-33163: Upgrade pip to 9.0.3 and setuptools to v39.0.1.
bpo-33012: gcc 8 has added a new warning heuristic to detect invalid function casts and a stock python build seems to hit that warning quite often. The most common is the cast of a METH_NOARGS function (that uses just one argument) to a PyCFunction. Fix this by adding a dummy argument to all functions that implement METH_NOARGS.
bpo-32898: Fix the python debug build when using COUNT_ALLOCS.
bpo-29442: Replace optparse with argparse in setup.py
Windows¶
bpo-35890: Fix API calling consistency of GetVersionEx and wcstok.
bpo-32560: The
py
launcher now forwards itsSTARTUPINFO
structure to child processes.bpo-35854: Fix EnvBuilder and –symlinks in venv on Windows
bpo-35811: Avoid propagating venv settings when launching via py.exe
bpo-35797: Fix default executable used by the multiprocessing module
bpo-35758: Allow building on ARM with MSVC.
bpo-29734: Fix handle leaks in os.stat on Windows.
bpo-35596: Use unchecked PYCs for the embeddable distro to avoid zipimport restrictions.
bpo-35596: Fix vcruntime140.dll being added to embeddable distro multiple times.
bpo-35402: Update Windows build to use Tcl and Tk 8.6.9
bpo-35401: Updates Windows build to OpenSSL 1.1.0j
bpo-34977: venv on Windows will now use a python.exe redirector rather than copying the actual binaries from the base environment.
bpo-34977: Adds support for building a Windows App Store package
bpo-35067: Remove _distutils_findvs module and use vswhere.exe instead.
bpo-32557: Allow shutil.disk_usage to take a file path on Windows
bpo-34770: Fix a possible null pointer dereference in pyshellext.cpp.
bpo-34603: Fix returning structs from functions produced by MSVC
bpo-34581: Guard MSVC-specific code in socketmodule.c with
#ifdef _MSC_VER
.bpo-34532: Fixes exit code of list version arguments for py.exe.
bpo-34062: Fixed the ‘–list’ and ‘–list-paths’ arguments for the py.exe launcher
bpo-34225: Ensure INCLUDE and LIB directories do not end with a backslash.
bpo-34011: A suite of code has been changed which copied across DLLs and init.tcl from the running Python location into a venv being created. These copies are needed only when running from a Python source build, and the copying code is now only run when that is the case, rather than whenever a venv is created.
bpo-34006: Revert line length limit for Windows help docs. The line-length limit is not needed because the pages appear in a separate app rather than on a browser tab. It can also interact badly with the DPI setting.
bpo-31546: Restore running PyOS_InputHook while waiting for user input at the prompt. The restores integration of interactive GUI windows (such as Matplotlib figures) with the prompt on Windows.
bpo-30237: Output error when ReadConsole is canceled by CancelSynchronousIo instead of crashing.
bpo-33895: GIL is released while calling functions that acquire Windows loader lock.
bpo-33720: Reduces maximum marshal recursion depth on release builds.
bpo-29097: Fix bug where
datetime.fromtimestamp()
erroneously throws anOSError
on Windows for values between 0 and 86400. Patch by Ammar Askar.bpo-33316: PyThread_release_lock always fails
bpo-33184: Update Windows installer to use OpenSSL 1.1.0h.
bpo-32890: Fix usage of GetLastError() instead of errno in os.execve() and os.truncate().
bpo-33016: Fix potential use of uninitialized memory in nt._getfinalpathname
bpo-32903: Fix a memory leak in os.chdir() on Windows if the current directory is set to a UNC path.
bpo-32901: Update Tcl and Tk versions to 8.6.8
bpo-31966: Fixed WindowsConsoleIO.write() for writing empty data.
bpo-32409: Ensures activate.bat can handle Unicode contents.
bpo-32457: Improves handling of denormalized executable path when launching Python.
bpo-32370: Use the correct encoding for ipconfig output in the uuid module. Patch by Segev Finer.
bpo-29248: Fix
os.readlink()
on Windows, which was mistakenly treating thePrintNameOffset
field of the reparse data buffer as a number of characters instead of bytes. Patch by Craig Holmquist and SSE4.bpo-1104: Correctly handle string length in
msilib.SummaryInfo.GetProperty()
to prevent it from truncating the last character.
macOS¶
bpo-35401: Update macOS installer to use OpenSSL 1.1.0j.
bpo-35025: Properly guard the use of the
CLOCK_GETTIME
et al. macros intimemodule
on macOS.bpo-24658: On macOS, fix reading from and writing into a file with a size larger than 2 GiB.
bpo-34405: Update to OpenSSL 1.1.0i for macOS installer builds.
bpo-33635: In macOS stat on some file descriptors (/dev/fd/3 f.e) will result in bad file descriptor OSError. Guard against this exception was added in is_dir, is_file and similar methods. DirEntry.is_dir can also throw this exception so _RecursiveWildcardSelector._iterate_directories was also extended with the same error ignoring pattern.
bpo-13631: The .editrc file in user’s home directory is now processed correctly during the readline initialization through editline emulation on macOS.
bpo-33184: Update macOS installer build to use OpenSSL 1.1.0h.
bpo-32726: Build and link with private copy of Tcl/Tk 8.6 for the macOS 10.6+ installer. The 10.9+ installer variant already does this. This means that the Python 3.7 provided by the python.org macOS installers no longer need or use any external versions of Tcl/Tk, either system-provided or user-installed, such as ActiveTcl.
bpo-32901: Update macOS 10.9+ installer to Tcl/Tk 8.6.8.
bpo-31903: In
_scproxy
, drop the GIL when calling intoSystemConfiguration
to avoid deadlocks.
IDLE¶
bpo-35770: IDLE macosx deletes Options => Configure IDLE. It previously deleted Window => Zoom Height by mistake. (Zoom Height is now on the Options menu). On Mac, the settings dialog is accessed via Preferences on the IDLE menu.
bpo-35769: Change IDLE’s new file name from ‘Untitled’ to ‘untitled’
bpo-35660: Fix imports in idlelib.window.
bpo-35641: Proper format
calltip
when the function has no docstring.bpo-33987: Use ttk Frame for ttk widgets.
bpo-34055: Fix erroneous ‘smart’ indents and newlines in IDLE Shell.
bpo-35591: Find Selection now works when selection not found.
bpo-35196: Speed up squeezer line counting.
bpo-35598: Update config_key: use PEP 8 names and ttk widgets, make some objects global, and add tests.
bpo-28097: Add Previous/Next History entries to Shell menu.
bpo-35208: Squeezer now properly counts wrapped lines before newlines.
bpo-35555: Gray out Code Context menu entry when it’s not applicable.
bpo-35521: Document the IDLE editor code context feature. Add some internal references within the IDLE doc.
bpo-22703: The Code Context menu label now toggles between Show/Hide Code Context. The Zoom Height menu now toggles between Zoom/Restore Height. Zoom Height has moved from the Window menu to the Options menu.
bpo-35213: Where appropriate, use ‘macOS’ in idlelib.
bpo-34864: On macOS, warn if the system preference “Prefer tabs when opening documents” is set to “Always”.
bpo-34864: Document two IDLE on MacOS issues. The System Preferences Dock “prefer tabs always” setting disables some IDLE features. Menus are a bit different than as described for Windows and Linux.
bpo-35202: Remove unused imports from lib/idlelib
bpo-33000: Document that IDLE’s shell has no line limit. A program that runs indefinitely can overfill memory.
bpo-23220: Explain how IDLE’s Shell displays output.
bpo-35099: Improve the doc about IDLE running user code. The section is renamed from “IDLE – console differences” is renamed “Running user code”. It mostly covers the implications of using custom sys.stdxxx objects.
bpo-35097: Add IDLE doc subsection explaining editor windows. Topics include opening, title and status bar, .py* extension, and running.
bpo-35093: Document the IDLE document viewer in the IDLE doc. Add a paragraph in “Help and preferences”, “Help sources” subsection.
bpo-35088: Update idlelib.help.copy_string docstring. We now use git and backporting instead of hg and forward merging.
bpo-35087: Update idlelib help files for the current doc build. The main change is the elimination of chapter-section numbers.
bpo-34548: Use configured color theme for read-only text views.
bpo-1529353: Enable “squeezing” of long outputs in the shell, to avoid performance degradation and to clean up the history without losing it. Squeezed outputs may be copied, viewed in a separate window, and “unsqueezed”.
bpo-34047: Fixed mousewheel scrolling direction on macOS.
bpo-34275: Make IDLE calltips always visible on Mac. Some MacOS-tk combinations need .update_idletasks(). Patch by Kevin Walzer.
bpo-34120: Fix unresponsiveness after closing certain windows and dialogs.
bpo-33975: Avoid small type when running htests. Since part of the purpose of human-viewed tests is to determine that widgets look right, it is important that they look the same for testing as when running IDLE.
bpo-33905: Add test for idlelib.stackview.StackBrowser.
bpo-33924: Change mainmenu.menudefs key ‘windows’ to ‘window’. Every other menudef key is lowercase version of main menu entry.
bpo-33906: Rename idlelib.windows as window Match Window on the main menu and remove last plural module name.
bpo-33917: Fix and document idlelib/idle_test/template.py. The revised file compiles, runs, and tests OK. idle_test/README.txt explains how to use it to create new IDLE test files.
bpo-33904: IDLE: In rstrip, rename class RstripExtension as Rstrip
bpo-33907: For consistency and clarity, rename an IDLE module and classes. Module calltips and its class CallTips are now calltip and Calltip. In module calltip_w, class CallTip is now CalltipWindow.
bpo-33856: Add “help” in the welcome message of IDLE
bpo-33839: IDLE: refactor ToolTip and CallTip and add documentation and tests
bpo-33855: Minimally test all IDLE modules. Add missing files, import module, instantiate classes, and check coverage. Check existing files.
bpo-33656: On Windows, add API call saying that tk scales for DPI. On Windows 8.1+ or 10, with DPI compatibility properties of the Python binary unchanged, and a monitor resolution greater than 96 DPI, this should make text and lines sharper. It should otherwise have no effect.
bpo-33768: Clicking on a context line moves that line to the top of the editor window.
bpo-33763: IDLE: Use read-only text widget for code context instead of label widget.
bpo-33664: Scroll IDLE editor text by lines. Previously, the mouse wheel and scrollbar slider moved text by a fixed number of pixels, resulting in partial lines at the top of the editor box. The change also applies to the shell and grep output windows, but not to read-only text views.
bpo-33679: Enable theme-specific color configuration for Code Context. Use the Highlights tab to see the setting for built-in themes or add settings to custom themes.
bpo-33642: Display up to maxlines non-blank lines for Code Context. If there is no current context, show a single blank line.
bpo-33628: IDLE: Cleanup codecontext.py and its test.
bpo-33564: IDLE’s code context now recognizes async as a block opener.
bpo-21474: Update word/identifier definition from ascii to unicode. In text and entry boxes, this affects selection by double-click, movement left/right by control-left/right, and deletion left/right by control-BACKSPACE/DEL.
bpo-33204: IDLE: consistently color invalid string prefixes. A ‘u’ string prefix cannot be paired with either ‘r’ or ‘f’. Consistently color as much of the prefix, starting at the right, as is valid. Revise and extend colorizer test.
bpo-32984: Set
__file__
while running a startup file. Like Python, IDLE optionally runs one startup file in the Shell window before presenting the first interactive input prompt. For IDLE,-s
runs a file named in environmental variableIDLESTARTUP
orPYTHONSTARTUP
;-r file
runsfile
. Python sets__file__
to the startup file name before running the file and unsets it before the first prompt. IDLE now does the same when run normally, without the-n
option.bpo-32940: Simplify and rename StringTranslatePseudoMapping in pyparse.
bpo-32916: Change
str
tocode
in pyparse.bpo-32905: Remove unused code in pyparse module.
bpo-32874: Add tests for pyparse.
bpo-32837: Using the system and place-dependent default encoding for open() is a bad idea for IDLE’s system and location-independent files.
bpo-32826: Add “encoding=utf-8” to open() in IDLE’s test_help_about. GUI test test_file_buttons() only looks at initial ascii-only lines, but failed on systems where open() defaults to ‘ascii’ because readline() internally reads and decodes far enough ahead to encounter a non-ascii character in CREDITS.txt.
bpo-32831: Add docstrings and tests for codecontext.
bpo-32765: Update configdialog General tab docstring to add new widgets to the widget list.
Tools/Demos¶
bpo-35884: Add a benchmark script for timing various ways to access variables:
Tools/scripts/var_access_benchmark.py
.bpo-34989: python-gdb.py now handles errors on computing the line number of a Python frame.
bpo-20260: Argument Clinic now has non-bitwise unsigned int converters.
bpo-32962: python-gdb now catches
UnicodeDecodeError
exceptions when callingstring()
.bpo-32962: python-gdb now catches ValueError on read_var(): when Python has no debug symbols for example.
bpo-33189: pygettext.py now recognizes only literal strings as docstrings and translatable strings, and rejects bytes literals and f-string expressions.
bpo-31920: Fixed handling directories as arguments in th