The __class__ cell used by zero-argument super() is now initialized from type.__new__ rather than __build_class__, so class methods relying on that will now work correctly when called from metaclass methods during class creation. Patch by Martin Teichmann.
Fix corrupted result from PyLong_FromLong(0) when Python is compiled with NSMALLPOSINTS = 0.
Implement formatting support for PEP 515. Initial patch by Chris Angelico.
In tarfile, expose copyfileobj bufsize to improve throughput. Patch by Jason Fried.
In f-strings, only allow backslashes inside the braces (where the
expressions are). This is a breaking change from the 3.6 alpha releases,
where backslashes are allowed anywhere in an f-string. Also, require that
expressions inside f-strings be enclosed within literal braces, and not
escapes like f'\x7b"hi"\x7d'.
Remove platform-specific directories from sys.path.
Add early-out for differencing from an empty set.
Prevents zipimport from unnecessarily encoding a filename (patch by Eryk Sun)
The __module__ attribute of extension classes and functions now is interned. This leads to more compact pickle data with protocol 4.
Rework CALL_FUNCTION* opcodes to produce shorter and more efficient bytecode. Patch by Demur Rumed, design by Serhiy Storchaka, reviewed by Serhiy Storchaka and Victor Stinner.
Implement tokenizing support for PEP 515. Patch by Georg Brandl.
Make "global after use" a SyntaxError, and ditto for nonlocal. Patch by Ivan Levkivskyi.
Implement PEP 525 -- Asynchronous Generators.
Implement PEP 526 -- Syntax for Variable Annotations. Patch by Ivan Levkivskyi.
Add a new private version to the builtin dict type, incremented at each dictionary creation and at each dictionary change. Implementation of the PEP 509.
A backslash-character pair that is not a valid escape sequence now generates a DeprecationWarning. Patch by Emanuel Barry.
dict implementation is changed like PyPy. It is more compact and preserves
insertion order. (Concept developed by Raymond Hettinger and patch by Inada
Naoki.)
Remove unnecessary error checks in exec_builtin_or_dynamic().
Added BUILD_STRING opcode. Optimized f-strings evaluation.
Python now requires systems with inttypes.h and stdint.h
Require platforms to support long long. Python hasn't compiled without
long long for years, so this is basically a formality.
Removed support for Windows CE. It was never finished, and Windows CE is no longer a relevant platform for Python.
Implement PEP 523.
A left shift of zero by a large integer no longer attempts to allocate large amounts of memory.
In int-to-decimal-string conversion, improve the estimate of the intermediate memory required, and remove an unnecessarily strict overflow check. Patch by Serhiy Storchaka.
In long_invert, be more careful about modifying object returned by long_add, and remove an unnecessary check for small longs. Thanks Oren Milman for analysis and patch.
Support passing the bytes/bytearray.translate() "delete" argument by keyword.
Properly clear out a generator's frame's backreference to the generator to prevent crashes in frame.clear().
Fix a crash when a coroutine that has not been awaited is finalized with warnings-as-errors enabled.
Fix another issue found by PVS-Studio: Null pointer check after use of 'def' in _PyState_AddModule(). Initial patch by Christian Heimes.
The modulo operation applied to bool and other int subclasses now
always returns an int. Previously the return type depended on the input
values. Patch by Xiang Zhang.
int() now always returns an instance of exact int.
Fix a minor bug in integer true division; this bug could potentially have caused off-by-one-ulp results on platforms with unreliable ldexp implementations.
Make class definition namespace ordered by default.
Fix an overflow check in List_New: the original code was checking
against Py_SIZE_MAX instead of the correct upper bound of
Py_SSIZE_T_MAX. Patch by Xiang Zhang.
Multi-phase extension module import now correctly allows the m_methods
field to be used to add module level functions to instances of non-module
types returned from Py_create_mod. Patch by Xiang Zhang.
The round() function accepted a second None argument for some types but not for others. Fixed the inconsistency by accepting None for all numeric types.
Warn if a submodule argument to "python -m" or runpy.run_module() is found in sys.modules after parent packages are imported, but before the submodule is executed.
Make only type() itself accept the one-argument form. Patch by Eryk Sun and Emanuel Barry.
Fix a SystemError in the implementation of "raise" statement. In a brand new thread, raise a RuntimeError since there is no active exception to reraise. Patch written by Xiang Zhang.
Implement PEP 530 -- asynchronous comprehensions.
Fix memory leak in codeobject.c
Fix crash in os.spawnv() with no elements in args
Always raise ValueError for negative compileall.compile_dir(workers=...) parameter, even when multithreading is unavailable.
Use sqlite3_get_autocommit() instead of setting Connection->inTransaction manually.
Attributes tm_gmtoff and tm_zone are now available on all platforms in the return values of time.localtime() and time.gmtime().
Regular expression match object groups are now accessible using __getitem__. "mo[x]" is equivalent to "mo.group(x)".
sqlite3 no longer implicitly commit an open transaction before DDL statements.
Add a module parameter to collections.namedtuple().
Inline flags now should be used only at the start of the regular expression. Deprecation warning is emitted if uses them in the middle of the regular expression.
xmlrpc now supports unmarshalling additional data types used by Apache XML-RPC implementation for numerics and None.
Fixed parsing inline verbose flag in regular expressions.
Add client-side SSL session resumption to the ssl module.
Deprecate ssl-related arguments in favor of SSLContext. The deprecation include manual creation of SSLSocket and certfile/keyfile (or similar) in ftplib, httplib, imaplib, smtplib, poplib and urllib.
SSLContext has improved default settings: OP_NO_SSLv2, OP_NO_SSLv3, OP_NO_COMPRESSION, OP_CIPHER_SERVER_PREFERENCE, OP_SINGLE_DH_USE, OP_SINGLE_ECDH_USE and HIGH ciphers without MD5.
Changed some RuntimeError's in the zipfile module to more appropriate types. Improved some error messages and debugging output.
json.load and json.loads now support binary input encoded as UTF-8,
UTF-16 or UTF-32. Patch by Serhiy Storchaka.
the pure Python fallback implementation of functools.partial now matches
the behaviour of its accelerated C counterpart for subclassing, pickling and
text representation purposes. Patch by Emanuel Barry and Serhiy Storchaka.
Fix possible integer overflows and crashes in the mmap module with unusual usage patterns.
Fix the ability to pass the --link-objects option to the distutils build_ext command.
itertools.count() no longer rounds non-integer step in range between 1.0 and 2.0 to 1.
Pdb now supports the 'readrc' keyword argument to control whether .pdbrc files should be read. Patch by Martin Matusiak and Sam Kimbrel.
Update the lib2to3 grammar to handle the unpacking generalizations added in 3.5.
mailcap now respects the order of the lines in the mailcap files ("first match"), as required by RFC 1542. Patch by Michael Lazar.
Convert re flag constants to IntFlag.
Convert all ssl module constants to IntEnum and IntFlags. SSLContext properties now return flags and enums.
Add Flag, IntFlag, and auto() to enum module.
Added support of modifier spans in regular expressions.
Validates persist parameter when opening MSI database
xml.etree.ElementTree nows preserves whitespaces in attributes (Patch by Duane Griffin. Reviewed and approved by Stefan Behnel.)
Fixed calculation of line length used for the base64 CTE in the new email policies.
Fix call order in OrderedDict.__init__().
email.generator.DecodedGenerator now supports the policy keyword.
Remove undocumented modules from Lib/plat-*: IN, CDROM, DLFCN, TYPES,
CDIO, and STROPTS.
Don't pass str(_charset) to MIMEText.set_payload(). Patch by Claude Paroz.
The new email API is no longer provisional, and the docs have been reorganized and rewritten to emphasize the new API.
urllib now includes an Accept: */* header among the default headers.
This makes the results of REST API requests more consistent and predictable
especially when proxy servers are involved.
lib2to3.pgen3.driver.load_grammar() now creates a stable cache file between runs given the same Grammar.txt input regardless of the hash randomization setting.
Allow ImportErrors in encoding implementation to propagate.
Support path-like objects in importlib.util.
Avoid zero-length memcpy() etc calls with null source pointers in the "ctypes" and "array" modules.
Break email header lines only on the RFC specified CR and LF characters, not on arbitrary unicode line breaks. This also fixes a bug in HTTP header parsing.
The email.mime classes now all accept an optional policy keyword.
Fix email iter_attachments incorrect mutation of payload list.
Add SHA-3 and SHAKE support to hashlib module.
Eliminate a tautological-pointer-compare warning in _scproxy.c.
The :func:`os.urandom` function does now block on Linux 3.17 and newer until the system urandom entropy pool is initialized to increase the security. This change is part of the PEP 524.
Expose the Linux getrandom() syscall as a new :func:`os.getrandom`
function. This change is part of the PEP 524.
Fix ssl module's parsing of GEN_RID subject alternative name fields in X.509 certs.
Add random.choices().
Improved error reporting about truncated pickle data in C implementation of unpickler. UnpicklingError is now raised instead of AttributeError and ValueError in some cases.
Add BLAKE2 (blake2b and blake2s) to hashlib.
Optimized globbing in pathlib by using os.scandir(); it is now about 1.5--4 times faster.
Optimized glob() and iglob() functions in the glob module; they are now about 3--6 times faster.
Add scrypt (password-based key derivation function) to hashlib module (requires OpenSSL 1.1.0).
Remove 3DES from ssl module's default cipher list to counter measure sweet32 attack (:cve:`2016-2183`).
Add ChaCha20 Poly1305 to ssl module's default cipher list. (Required OpenSSL 1.1.0 or LibreSSL).
Check return value of winsound.MessageBeep.
Add SSLContext.get_ciphers() method to get a list of all enabled ciphers.
Add AF_ALG (Linux Kernel crypto) to socket module.
Port ssl and hashlib module to OpenSSL 1.1.0.
Fix support for SND_MEMORY in winsound.PlaySound. Based on a patch by Tim Lesher.
Add support for IEEE 754 half-precision floats to the struct module. Based on a patch by Eli Stevens.
Deprecated extra_path distribution option in distutils packaging.
Add new cmath constants: cmath.inf and cmath.nan to match
math.inf and math.nan, and also cmath.infj and cmath.nanj to
match the format used by complex repr.
The csv.DictReader now returns rows of type OrderedDict. (Contributed by Steve Holden.)
Remove support for passing a file descriptor to os.access. It never worked but previously didn't raise.
Fix error when distutils encounters symlink.
Fixed possible bugs when setting sqlite3.Connection.isolation_level. Based on patch by Xiang Zhang.
Fixed a crash in sqlite3.Connection.cursor() when a factory creates not a cursor. Patch by Xiang Zhang.
Avoid spurious output on OS X with Gnu Readline.
Restore deterministic behavior of random.Random().seed() for string seeds using seeding version 1. Allows sequences of calls to random() to exactly match those obtained in Python 2. Patch by Nofar Schnider.
Fix a regression in Connection.commit(). Statements should not be reset after a commit.
Chunked transfer encoding support added to http.client.HTTPConnection requests. The urllib.request.AbstractHTTPHandler class does not enforce a Content-Length header any more. If a HTTP request has a file or iterable body, but no Content-Length header, the library now falls back to use chunked transfer-encoding.
A new version of typing.py from https://github.com/python/typing: - Collection (only for 3.6) (Issue #27598) - Add FrozenSet to __all__ (upstream #261) - fix crash in _get_type_vars() (upstream #259) - Remove the dict constraint in ForwardRef._eval_type (upstream #252)
Make _normalize parameter to Fraction constructor keyword-only, so
that Fraction(2, 3, 4) now raises TypeError.
Fix unnormalised Fraction.__pow__ result in the case of negative
exponent and negative base.
cursor.description is now available for queries using CTEs.
In distutils sdists, simply produce the "gztar" (gzipped tar format) distributions on all platforms unless "formats" is supplied.
posixpath.ismount now correctly recognizes mount points which the user does not have permission to access.
On Linux, ctypes.util.find_library now looks in LD_LIBRARY_PATH for shared libraries.
exit message for code.interact is now configurable.
Improved behaviour of logging.handlers.QueueListener. Thanks to Paulo Andrade and Petr Viktorin for the analysis and patch.
Distributed reference counting added to multiprocessing to support nesting of shared values / proxy objects.
Improves readability of multiprocessing error message. Thanks to Wojciech Walczak for patch.
asyncio: Add set_protocol / get_protocol to Transports.
asyncio: Set TCP_NODELAY by default.
Add 'interrupt execution' (^C) to Shell menu. Patch by Roger Serwy, updated by Bayard Randel.
Stop IDLE tests from 'flashing' gui widgets on the screen.
Consistently group and sort imports within idlelib modules.
add larger font sizes for classroom projection.
Add version to title of IDLE help window.
In section on IDLE -- console differences, mention that using exec means that __builtins__ is defined for each statement.
Fix 3.6.0a3 regression that prevented custom key sets from being selected when no custom theme was defined.
Excluded underscored names and other private API from limited API.
Add support for path-like objects in PyUnicode_FSConverter() & PyUnicode_FSDecoder().
Additional tests for the math module. Patch by Francisco Couzo.
Skip math and cmath tests that fail on OS X 10.4 due to a poor libm implementation of tan.
Improve test_math and test_cmath coverage and rigour. Patch by Jeff Allen.
Call gc.collect() before checking each test for "dangling threads", since the dangling threads are weak references.
Fix clean target in freeze makefile (patch by Lisa Roach)
Update message in validate_ucrtbase.py
Deprecate building _ctypes with the bundled copy of libffi on non-OSX UNIX platforms.
Cause lack of llvm-profdata tool when using clang as required for PGO
linking to be a configure time error rather than make time when
--with-optimizations is enabled. Also improve our ability to find the
llvm-profdata tool on MacOS and some Linuxes.
Support for DTrace and SystemTap probes.
The profile-opt build now applies PGO to the built-in modules.
Add the --with-optimizations flag to turn on LTO and PGO build support when available.
Set platform triplets for Android builds.
Update references to the $(LIBPL) installation path on AIX. This path was changed in 3.2a4.
Update OS X installer to use SQLite 3.14.1 and XZ 5.2.2.
Fix LTO builds on OS X.
Build OS X installer with a private copy of OpenSSL. Also provide a sample Install Certificates command script to install a set of root certificates from the third-party certifi module.
Get Tools/scripts/fixcid.py working with Python 3 and the current "re" module, avoid invalid Python backslash escapes, and fix a bug parsing escaped C quote signs.
Update xz dependency to 5.2.2 and build it from source.
Ensures TargetDir is set before continuing with custom install.
Windows console doesn't input or print Unicode (PEP 528)
Change file system encoding on Windows to UTF-8 (PEP 529)
Opt-out of MAX_PATH on Windows 10
Adds encoding and errors parameters to subprocess.
Adds oem encoding, alias ansi to mbcs, move aliasmbcs to codec lookup.
The functions of the winsound module now accept keyword arguments.
Build full text search support into SQLite on Windows.
Adds new icons for Python files and processes on Windows. Designs by Cherry Wang.
Update sqlite to 3.14.1.0 on Windows.