Python Changelog

New in version 3.5.0 RC 2

August 25th, 2015
  • Core and Builtins:
  • Issue #21167: NAN operations are now handled correctly when python is compiled with ICC even if -fp-model strict is not specified.
  • Library:
  • Issue #24764: cgi.FieldStorage.read_multi() now ignores the Content-Length header in part headers. Patch written by Peter Landry and reviewed by Pierre Quentel.
  • Issue #24774: Fix docstring in http.server.test. Patch from Chiu-Hsiang Hsu.
  • Issue #21159: Improve message in configparser.InterpolationMissingOptionError. Patch from Łukasz Langa.
  • Issue #24847: Fixes tcltk installer layout of VC runtime DLL
  • Issue #24839: platform._syscmd_ver raises DeprecationWarning
  • Issue #24867: Fix Task.get_stack() for ‘async def’ coroutines
  • Documentation:
  • Issue #23725: Overhaul tempfile docs. Note deprecated status of mktemp. Patch from Zbigniew Jędrzejewski-Szmek.

New in version 3.5.0 RC 1 (August 11th, 2015)

  • Core and Builtins:
  • Issue #24667: Resize odict in all cases that the underlying dict resizes.
  • Library:
  • Issue #24824: Signatures of codecs.encode() and codecs.decode() now are compatible with pydoc.
  • Issue #24634: Importing uuid should not try to load libc on Windows
  • Issue #24798: _msvccompiler.py doesn’t properly support manifests
  • Issue #4395: Better testing and documentation of binary operators. Patch by Martin Panter.
  • Issue #23973: Update typing.py from GitHub repo.
  • Issue #23004: mock_open() now reads binary data correctly when the type of read_data is bytes. Initial patch by Aaron Hill.
  • Issue #23888: Handle fractional time in cookie expiry. Patch by ssh.
  • Issue #23652: Make it possible to compile the select module against the libc headers from the Linux Standard Base, which do not include some EPOLL macros. Patch by Matt Frank.
  • Issue #22932: Fix timezones in email.utils.formatdate. Patch from Dmitry Shachnev.
  • Issue #23779: imaplib raises TypeError if authenticator tries to abort. Patch from Craig Holmquist.
  • Issue #23319: Fix ctypes.BigEndianStructure, swap correctly bytes. Patch written by Matthieu Gautier.
  • Issue #23254: Document how to close the TCPServer listening socket. Patch from Martin Panter.
  • Issue #19450: Update Windows and OS X installer builds to use SQLite 3.8.11.
  • Issue #17527: Add PATCH to wsgiref.validator. Patch from Luca Sbardella.
  • Issue #23812: Fix asyncio.Queue.get() to avoid loosing items on cancellation. Patch by Gustavo J. A. M. Carneiro.
  • Issue #24791: Fix grammar regression for call syntax: ‘g(*a or b)’.
  • Documentation:
  • Issue #24129: Clarify the reference documentation for name resolution. This includes removing the assumption that readers will be familiar with the name resolution scheme Python used prior to the introduction of lexical scoping for function namespaces. Patch by Ivan Levkivskyi.
  • Issue #20769: Improve reload() docs. Patch by Dorian Pula.
  • Issue #23589: Remove duplicate sentence from the FAQ. Patch by Yongzhi Pan.
  • Issue #24729: Correct IO tutorial to match implementation regarding encoding parameter to open function.
  • Tests:
  • Issue #24751: When running regrtest with the -w command line option, a test run is no longer marked as a failure if all tests succeed when re-run.

New in version 3.5.0 Beta 3 (July 6th, 2015)

  • Highlights:
  • PEP 448, additional unpacking generalizations
  • PEP 461, adding support for "%-formatting" for bytes and bytearray objects
  • PEP 465, a new operator (@) for matrix multiplication
  • PEP 471, os.scandir(), a faster alternative to os.walk()
  • PEP 475, adding support for automatic retries of interrupted system calls
  • PEP 479, change StopIteration handling inside generators
  • PEP 484, the typing module, a new standard for type annotations
  • PEP 486, making the Windows Python launcher aware of virtual environments
  • PEP 488, eliminating .pyo files
  • PEP 489, multi-phase extension module initialization
  • PEP 492, coroutines with async and await syntax

New in version 3.5.0 Beta 2 (June 1st, 2015)

  • Core and Built-ins:
  • Issue #24284: The startswith and endswith methods of the str class no longer return True when finding the empty string and the indexes are completely out of range.
  • Issue #24115: Update uses of PyObject_IsTrue(), PyObject_Not(), PyObject_IsInstance(), PyObject_RichCompareBool() and _PyDict_Contains() to check for and handle errors correctly.
  • Issue #24328: Fix importing one character extension modules.
  • Issue #11205: In dictionary displays, evaluate the key before the value.
  • Issue #24285: Fixed regression that prevented importing extension modules from inside packages. Patch by Petr Viktorin.
  • Library:
  • Issue #5633: Fixed timeit when the statement is a string and the setup is not.
  • Issue #24326: Fixed audioop.ratecv() with non-default weightB argument. Original patch by David Moore.
  • Issue #16991: Add a C implementation of OrderedDict.
  • Issue #23934: Fix inspect.signature to fail correctly for builtin types lacking signature information. Initial patch by James Powell.

New in version 3.5.0 Beta 1 (May 25th, 2015)

  • New features and changes:
  • PEP 448, additional unpacking generalizations
  • PEP 461, adding support for "%-formatting" for bytes and bytearray objects
  • PEP 465, a new operator (@) for matrix multiplication
  • PEP 471, os.scandir(), a faster alternative to os.walk()
  • PEP 475, adding support for automatic retries of interrupted system calls
  • PEP 479, change StopIteration handling inside generators
  • PEP 484, the typing module, a new standard for type annotations
  • PEP 486, making the Windows Python launcher aware of virtual environments
  • PEP 488, eliminating .pyo files
  • PEP 489, multi-phase extension module initialization
  • PEP 492, coroutines with async and await syntax

New in version 3.5.0 Alpha 4 (April 20th, 2015)

  • Highlights:
  • PEP 461, adding support for "%-formatting" for bytes and bytearray objects
  • PEP 465, a new operator (@) for matrix multiplication
  • PEP 471, os.scandir()
  • PEP 475, adding support for automatic retries of interrupted system calls
  • PEP 486, making the Windows Python launcher aware of virtual environments
  • PEP 488, eliminating .pyo files
  • Core and Builtins:
  • Issue #22980: Under Linux, GNU/KFreeBSD and the Hurd, C extensions now include the architecture triplet in the extension name, to make it easy to test builds for different ABIs in the same working tree. Under OS X, the extension name now includes PEP 3149-style information.
  • Issue #22631: Added Linux-specific socket constant CAN_RAW_FD_FRAMES. Patch courtesy of Joe Jevnik.
  • Issue #23731: Implement PEP 488: removal of .pyo files.
  • Issue #23726: Don’t enable GC for user subclasses of non-GC types that don’t add any new fields. Patch by Eugene Toder.
  • Issue #23309: Avoid a deadlock at shutdown if a daemon thread is aborted while it is holding a lock to a buffered I/O object, and the main thread tries to use the same I/O object (typically stdout or stderr). A fatal error is emitted instead.
  • Issue #22977: Fixed formatting Windows error messages on Wine. Patch by Martin Panter.
  • Issue #23466: %c, %o, %x, and %X in bytes formatting now raise TypeError on non-integer input.
  • Library:
  • Issue #16914: new debuglevel 2 in smtplib adds timestamps to debug output.
  • Issue #7159: urllib.request now supports sending auth credentials automatically after the first 401. This enhancement is a superset of the enhancement from issue #19494 and supersedes that change.
  • Issue #23703: Fix a regression in urljoin() introduced in 901e4e52b20a. Patch by Demian Brecht.
  • Issue #4254: Adds _curses.update_lines_cols() Patch by Arnon Yaari
  • Issue 19933: Provide default argument for ndigits in round. Patch by Vajrasky Kok.
  • Issue #23193: Add a numeric_owner parameter to tarfile.TarFile.extract and tarfile.TarFile.extractall. Patch by Michael Vogt and Eric Smith.
  • Issue #23342: Add a subprocess.run() function than returns a CalledProcess instance for a more consistent API than the existing call* functions.
  • Issue #21217: inspect.getsourcelines() now tries to compute the start and end lines from the code object, fixing an issue when a lambda function is used as decorator argument. Patch by Thomas Ballinger and Allison Kaptur.
  • Issue #23811: Add missing newline to the PyCompileError error message. Patch by Alex Shkop.
  • Issue #21116: Avoid blowing memory when allocating a multiprocessing shared array that’s larger than 50% of the available RAM. Patch by Médéric Boquien.
  • Issue #22982: Improve BOM handling when seeking to multiple positions of a writable text file.
  • Issue #23464: Removed deprecated asyncio JoinableQueue.
  • Issue #23529: Limit the size of decompressed data when reading from GzipFile, BZ2File or LZMAFile. This defeats denial of service attacks using compressed bombs (i.e. compressed payloads which decompress to a huge size). Patch by Martin Panter and Nikolaus Rath.
  • Issue #21859: Added Python implementation of io.FileIO.
  • Issue #23865: close() methods in multiple modules now are idempotent and more robust at shutdown. If they need to release multiple resources, all are released even if errors occur.
  • Issue #23400: Raise same exception on both Python 2 and 3 if sem_open is not available. Patch by Davin Potts.
  • Issue #10838: The subprocess now module includes SubprocessError and TimeoutError in its list of exported names for the users wild enough to use from subprocess import *.
  • Issue #23411: Added DefragResult, ParseResult, SplitResult, DefragResultBytes, ParseResultBytes, and SplitResultBytes to urllib.parse.__all__. Patch by Martin Panter.
  • Issue #23881: urllib.request.ftpwrapper constructor now closes the socket if the FTP connection failed to fix a ResourceWarning.
  • Issue #23853: socket.socket.sendall() does no more reset the socket timeout each time data is sent successfuly. The socket timeout is now the maximum total duration to send all data.
  • Issue #22721: An order of multiline pprint output of set or dict containing orderable and non-orderable elements no longer depends on iteration order of set or dict.
  • Issue #15133: _tkinter.tkapp.getboolean() now supports Tcl_Obj and always returns bool. tkinter.BooleanVar now validates input values (accepted bool, int, str, and Tcl_Obj). tkinter.BooleanVar.get() now always returns bool.
  • Issue #10590: xml.sax.parseString() now supports string argument.
  • Issue #23338: Fixed formatting ctypes error messages on Cygwin. Patch by Makoto Kato.
  • Issue #15582: inspect.getdoc() now follows inheritance chains.
  • Issue #2175: SAX parsers now support a character stream of InputSource object.
  • Issue #16840: Tkinter now supports 64-bit integers added in Tcl 8.4 and arbitrary precision integers added in Tcl 8.5.
  • Issue #23834: Fix socket.sendto(), use the C Py_ssize_t type to store the result of sendto() instead of the C int type.
  • Issue #23618: socket.socket.connect() now waits until the connection completes instead of raising InterruptedError if the connection is interrupted by signals, signal handlers don’t raise an exception and the socket is blocking or has a timeout. socket.socket.connect() still raise InterruptedError for non-blocking sockets.
  • Issue #21526: Tkinter now supports new boolean type in Tcl 8.5.
  • Issue #23836: Fix the faulthandler module to handle reentrant calls to its signal handlers.
  • Issue #23838: linecache now clears the cache and returns an empty result on MemoryError.
  • Issue #10395: Added os.path.commonpath(). Implemented in posixpath and ntpath. Based on patch by Rafik Draoui.
  • Issue #23611: Serializing more “lookupable” objects (such as unbound methods or nested classes) now are supported with pickle protocols < 4.
  • Issue #13583: sqlite3.Row now supports slice indexing.
  • Issue #18473: Fixed 2to3 and 3to2 compatible pickle mappings. Fixed ambigious reverse mappings. Added many new mappings. Import mapping is no longer applied to modules already mapped with full name mapping.
  • Issue #23485: select.select() is now retried automatically with the recomputed timeout when interrupted by a signal, except if the signal handler raises an exception. This change is part of the PEP 475.
  • Issue #23752: When built from an existing file descriptor, io.FileIO() now only calls fstat() once. Before fstat() was called twice, which was not necessary.
  • Issue #23704: collections.deque() objects now support __add__, __mul__, and __imul__().
  • Issue #23171: csv.Writer.writerow() now supports arbitrary iterables.
  • Issue #23745: The new email header parser now handles duplicate MIME parameter names without error, similar to how get_param behaves.
  • Issue #22117: Fix os.utime(), it now rounds the timestamp towards minus infinity (-inf) instead of rounding towards zero.
  • Issue #23310: Fix MagicMock’s initializer to work with __methods__, just like configure_mock(). Patch by Kasia Jachim.
  • Build:
  • Issue #23817: FreeBSD now uses “1.0” the the SOVERSION as other operating systems, instead of just “1”.
  • Issue #23501: Argument Clinic now generates code into separate files by default.
  • Tests:
  • Issue #23799: Added test.support.start_threads() for running and cleaning up multiple threads.
  • Issue #22390: test.regrtest now emits a warning if temporary files or directories are left after running a test.
  • Tools/Demos:
  • Issue #18128: pygettext now uses standard +NNNN format in the POT-Creation-Date header.
  • Issue #23935: Argument Clinic’s understanding of format units accepting bytes, bytearrays, and buffers is now consistent with both the documentation and the implementation.
  • Issue #23944: Argument Clinic now wraps long impl prototypes at column 78.
  • Issue #20586: Argument Clinic now ensures that functions without docstrings have signatures.
  • Issue #23492: Argument Clinic now generates argument parsing code with PyArg_Parse instead of PyArg_ParseTuple if possible.
  • Issue #23500: Argument Clinic is now smarter about generating the “#ifndef” (empty) definition of the methoddef macro: it’s only generated once, even if Argument Clinic processes the same symbol multiple times, and it’s emitted at the end of all processing rather than immediately after the first use.
  • C API:
  • Issue #23998: PyImport_ReInitLock() now checks for lock allocation error

New in version 3.5.0 Alpha 3 (March 30th, 2015)

  • Core and Builtins:
  • Issue #23466: %c, %o, %x, and %X in bytes formatting now raise TypeError on non-integer input.
  • Issue #23573: Increased performance of string search operations (str.find, str.index, str.count, the in operator, str.split, str.partition) with arguments of different kinds (UCS1, UCS2, UCS4).
  • Issue #23753: Python doesn’t support anymore platforms without stat() or fstat(), these functions are always required.
  • Issue #23681: The -b option now affects comparisons of bytes with int.
  • Issue #23632: Memoryviews now allow tuple indexing (including for multi-dimensional memoryviews).
  • Issue #23192: Fixed generator lambdas. Patch by Bruno Cauet.
  • Issue #23629: Fix the default __sizeof__ implementation for variable-sized objects.
  • Library:
  • Issue #23171: csv.Writer.writerow() now supports arbitrary iterables.
  • Issue #23745: The new email header parser now handles duplicate MIME parameter names without error, similar to how get_param behaves.
  • Issue #22117: Fix os.utime(), it now rounds the timestamp towards minus infinity (-inf) instead of rounding towards zero.
  • Issue #14260: The groupindex attribute of regular expression pattern object now is non-modifiable mapping.
  • Issue #23792: Ignore KeyboardInterrupt when the pydoc pager is active. This mimics the behavior of the standard unix pagers, and prevents pipepager from shutting down while the pager itself is still running.
  • Issue #23775: pprint() of OrderedDict now outputs the same representation as repr().
  • Issue #23765: Removed IsBadStringPtr calls in ctypes
  • Issue #22364: Improved some re error messages using regex for hints.
  • Issue #23742: ntpath.expandvars() no longer loses unbalanced single quotes.
  • Issue #21717: The zipfile.ZipFile.open function now supports ‘x’ (exclusive creation) mode.
  • Issue #21802: The reader in BufferedRWPair now is closed even when closing writer failed in BufferedRWPair.close().
  • Issue #23622: Unknown escapes in regular expressions that consist of '\' and ASCII letter now raise a deprecation warning and will be forbidden in Python 3.6.
  • Issue #23671: string.Template now allows to specify the “self” parameter as keyword argument. string.Formatter now allows to specify the “self” and the “format_string” parameters as keyword arguments.
  • Issue #23502: The pprint module now supports mapping proxies.
  • Issue #17530: pprint now wraps long bytes objects and bytearrays.
  • Issue #22687: Fixed some corner cases in breaking words in tetxtwrap. Got rid of quadratic complexity in breaking long words.
  • Issue #4727: The copy module now uses pickle protocol 4 (PEP 3154) and supports copying of instances of classes whose __new__ method takes keyword-only arguments.
  • Issue #23491: Added a zipapp module to support creating executable zip file archives of Python code. Registered ”.pyz” and ”.pyzw” extensions on Windows for these archives (PEP 441).
  • Issue #23657: Avoid explicit checks for str in zipapp, adding support for pathlib.Path objects as arguments.
  • Issue #23688: Added support of arbitrary bytes-like objects and avoided unnecessary copying of memoryview in gzip.GzipFile.write(). Original patch by Wolfgang Maier.
  • Issue #23252: Added support for writing ZIP files to unseekable streams.
  • Issue #21526: Tkinter now supports new boolean type in Tcl 8.5.
  • Issue #23647: Increase impalib’s MAXLINE to accommodate modern mailbox sizes.
  • Issue #23539: If body is None, http.client.HTTPConnection.request now sets Content-Length to 0 for PUT, POST, and PATCH headers to avoid 411 errors from some web servers.
  • Issue #22351: The nntplib.NNTP constructor no longer leaves the connection and socket open until the garbage collector cleans them up. Patch by Martin Panter.
  • Issue #23704: collections.deque() objects now support methods for index(), insert(), and copy(). This allows deques to be registered as a MutableSequence and it improves their substitutablity for lists.
  • Issue #23715: signal.sigwaitinfo() and signal.sigtimedwait() are now retried when interrupted by a signal not in the sigset parameter, if the signal handler does not raise an exception. signal.sigtimedwait() recomputes the timeout with a monotonic clock when it is retried.
  • Issue #23001: Few functions in modules mmap, ossaudiodev, socket, ssl, and codecs, that accepted only read-only bytes-like object now accept writable bytes-like object too.
  • Issue #23646: If time.sleep() is interrupted by a signal, the sleep is now retried with the recomputed delay, except if the signal handler raises an exception (PEP 475).
  • Issue #23136: _strptime now uniformly handles all days in week 0, including Dec 30 of previous year. Based on patch by Jim Carroll.
  • Issue #23700: Iterator of NamedTemporaryFile now keeps a reference to NamedTemporaryFile instance. Patch by Bohuslav Kabrda.
  • Issue #22903: The fake test case created by unittest.loader when it fails importing a test module is now picklable.
  • Issue #22181: On Linux, os.urandom() now uses the new getrandom() syscall if available, syscall introduced in the Linux kernel 3.17. It is more reliable and more secure, because it avoids the need of a file descriptor and waits until the kernel has enough entropy.
  • Issue #2211: Updated the implementation of the http.cookies.Morsel class. Setting attributes key, value and coded_value directly now is deprecated. update() and setdefault() now transform and check keys. Comparing for equality now takes into account attributes key, value and coded_value. copy() now returns a Morsel, not a dict. repr() now contains all attributes. Optimized checking keys and quoting values. Added new tests. Original patch by Demian Brecht.
  • Issue #18983: Allow selection of output units in timeit. Patch by Julian Gindi.
  • Issue #23631: Fix traceback.format_list when a traceback has been mutated.
  • Issue #23568: Add rdivmod support to MagicMock() objects. Patch by Håkan Lövdahl.
  • Issue #2052: Add charset parameter to HtmlDiff.make_file().
  • Issue #23138: Fixed parsing cookies with absent keys or values in cookiejar. Patch by Demian Brecht.
  • Issue #23051: multiprocessing.Pool methods imap() and imap_unordered() now handle exceptions raised by an iterator. Patch by Alon Diamant and Davin Potts.
  • Issue #23581: Add matmul support to MagicMock. Patch by Håkan Lövdahl.
  • Issue #23566: enable(), register(), dump_traceback() and dump_traceback_later() functions of faulthandler now accept file descriptors. Patch by Wei Wu.
  • Issue #22928: Disabled HTTP header injections in http.client. Original patch by Demian Brecht.
  • Issue #23615: Modules bz2, tarfile and tokenize now can be reloaded with imp.reload(). Patch by Thomas Kluyver.
  • Issue #23605: os.walk() now calls os.scandir() instead of os.listdir(). The usage of os.scandir() reduces the number of calls to os.stat(). Initial patch written by Ben Hoyt.
  • Build:
  • Issue #23585: make patchcheck will ensure the interpreter is built.
  • Tests:
  • Issue #22390: test.regrtest now emits a warning if temporary files or directories are left after running a test.
  • Issue #23583: Added tests for standard IO streams in IDLE.
  • Issue #22289: Prevent test_urllib2net failures due to ftp connection timeout.
  • Tools/Demos:
  • Issue #22826: The result of open() in Tools/freeze/bkfile.py is now better compatible with regular files (in particular it now supports the context management protocol).

New in version 3.5.0 Alpha 2 (March 9th, 2015)

  • Core and Builtins:
  • Issue #22980: Under Linux, C extensions now include bitness in the file name, to make it easy to test 32-bit and 64-bit builds in the same working tree.
  • Issue #23571: PyObject_Call() and PyCFunction_Call() now raise a SystemError if a function returns a result and raises an exception. The SystemError is chained to the previous exception.
  • Library:
  • Issue #22524: New os.scandir() function, part of the PEP 471: “os.scandir() function – a better and faster directory iterator”. Patch written by Ben Hoyt.
  • Issue #23103: Reduced the memory consumption of IPv4Address and IPv6Address.
  • Issue #21793: BaseHTTPRequestHandler again logs response code as numeric, not as stringified enum. Patch by Demian Brecht.
  • Issue #23476: In the ssl module, enable OpenSSL’s X509_V_FLAG_TRUSTED_FIRST flag on certificate stores when it is available.
  • Issue #23576: Avoid stalling in SSL reads when EOF has been reached in the SSL layer but the underlying connection hasn’t been closed.
  • Issue #23504: Added an __all__ to the types module.
  • Issue #23563: Optimized utility functions in urllib.parse.
  • Issue #7830: Flatten nested functools.partial.
  • Issue #20204: Added the __module__ attribute to _tkinter classes.
  • Issue #19980: Improved help() for non-recognized strings. help(‘’) now shows the help on str. help(‘help’) now shows the help on help(). Original patch by Mark Lawrence.
  • Issue #23521: Corrected pure python implementation of timedelta division.
  • Issue #21619: Popen objects no longer leave a zombie after exit in the with statement if the pipe was broken. Patch by Martin Panter.
  • Issue #22936: Make it possible to show local variables in tracebacks for both the traceback module and unittest.
  • Issue #15955: Add an option to limit the output size in bz2.decompress(). Patch by Nikolaus Rath.
  • Issue #6639: Module-level turtle functions no longer raise TclError after closing the window.
  • Issues #814253, #9179: Group references and conditional group references now work in lookbehind assertions in regular expressions.
  • Issue #23215: Multibyte codecs with custom error handlers that ignores errors consumed too much memory and raised SystemError or MemoryError. Original patch by Aleksi Torhamo.
  • Issue #5700: io.FileIO() called flush() after closing the file. flush() was not called in close() if closefd=False.
  • Issue #23374: Fixed pydoc failure with non-ASCII files when stdout encoding differs from file system encoding (e.g. on Mac OS).
  • Issue #23481: Remove RC4 from the SSL module’s default cipher list.
  • Issue #21548: Fix pydoc.synopsis() and pydoc.apropos() on modules with empty docstrings.
  • Issue #22885: Fixed arbitrary code execution vulnerability in the dbm.dumb module. Original patch by Claudiu Popa.
  • Issue #23239: ssl.match_hostname() now supports matching of IP addresses.
  • Issue #23146: Fix mishandling of absolute Windows paths with forward slashes in pathlib.
  • Issue #23096: Pickle representation of floats with protocol 0 now is the same for both Python and C implementations.
  • Issue #19105: pprint now more efficiently uses free space at the right.
  • Issue #14910: Add allow_abbrev parameter to argparse.ArgumentParser. Patch by Jonathan Paugh, Steven Bethard, paul j3 and Daniel Eriksson.
  • Issue #21717: tarfile.open() now supports ‘x’ (exclusive creation) mode.
  • Issue #23344: marshal.dumps() is now 20-25% faster on average.
  • Issue #20416: marshal.dumps() with protocols 3 and 4 is now 40-50% faster on average.
  • Issue #23421: Fixed compression in tarfile CLI. Patch by wdv4758h.
  • Issue #23367: Fix possible overflows in the unicodedata module.
  • Issue #23361: Fix possible overflow in Windows subprocess creation code.
  • logging.handlers.QueueListener now takes a respect_handler_level keyword argument which, if set to True, will pass messages to handlers taking handler levels into account.
  • Issue #19705: turtledemo now has a visual sorting algorithm demo. Original patch from Jason Yeo.
  • Build:
  • Issue #23445: pydebug builds now use “gcc -Og” where possible, to make the resulting executable faster.
  • Issue #23593: Update OS X 10.5 installer build to use OpenSSL 1.0.2.
  • C API:
  • Issue #20204: Deprecation warning is now raised for builtin type without the __module__ attribute.

New in version 3.4.3 (February 25th, 2015)

  • Library:
  • Issue #6639: Module-level turtle functions no longer raise TclError after closing the window.
  • Issues #814253, #9179: Warnings now are raised when group references and conditional group references are used in lookbehind assertions in regular expressions.
  • Issue #23215: Multibyte codecs with custom error handlers that ignores errors consumed too much memory and raised SystemError or MemoryError. Original patch by Aleksi Torhamo.
  • Issue #5700: io.FileIO() called flush() after closing the file. flush() was not called in close() if closefd=False.
  • Issue #23374: Fixed pydoc failure with non-ASCII files when stdout encoding differs from file system encoding (e.g. on Mac OS).
  • Issue #23481: Remove RC4 from the SSL module’s default cipher list.
  • Issue #21548: Fix pydoc.synopsis() and pydoc.apropos() on modules with empty docstrings.
  • Issue #22885: Fixed arbitrary code execution vulnerability in the dbm.dumb module. Original patch by Claudiu Popa.
  • Issue #23146: Fix mishandling of absolute Windows paths with forward slashes in pathlib.
  • Issue #23421: Fixed compression in tarfile CLI. Patch by wdv4758h.
  • Issue #23361: Fix possible overflow in Windows subprocess creation code.
  • Build:
  • Issue #23445: pydebug builds now use “gcc -Og” where possible, to make the resulting executable faster.

New in version 3.4.3 RC 1 (February 9th, 2015)

  • Core and Builtins:
  • Issue #22735: Fix many edge cases (including crashes) involving custom mro() implementations.
  • Issue #22896: Avoid using PyObject_AsCharBuffer(), PyObject_AsReadBuffer() and PyObject_AsWriteBuffer().
  • Issue #21295: Revert some changes (issue #16795) to AST line numbers and column offsets that constituted a regression.
  • Issue #21408: The default __ne__() now returns NotImplemented if __eq__() returned NotImplemented. Original patch by Martin Panter.
  • Issue #23321: Fixed a crash in str.decode() when error handler returned replacment string longer than mailformed input data.
  • Issue #23048: Fix jumping out of an infinite while loop in the pdb.
  • Issue #20335: bytes constructor now raises TypeError when encoding or errors is specified with non-string argument. Based on patch by Renaud Blanch.
  • Issue #22335: Fix crash when trying to enlarge a bytearray to 0x7fffffff bytes on a 32-bit platform.
  • Issue #22653: Fix an assertion failure in debug mode when doing a reentrant dict insertion in debug mode.
  • Issue #22643: Fix integer overflow in Unicode case operations (upper, lower, title, swapcase, casefold).
  • Issue #22604: Fix assertion error in debug mode when dividing a complex number by (nan+0j).
  • Issue #22470: Fixed integer overflow issues in “backslashreplace”, “xmlcharrefreplace”, and “surrogatepass” error handlers.
  • Issue #22520: Fix overflow checking when generating the repr of a unicode object.
  • Issue #22519: Fix overflow checking in PyBytes_Repr.
  • Issue #22518: Fix integer overflow issues in latin-1 encoding.
  • Issue #23165: Perform overflow checks before allocating memory in the _Py_char2wchar function.
  • Library:
  • Issue #23399: pyvenv creates relative symlinks where possible.
  • Issue #23099: Closing io.BytesIO with exported buffer is rejected now to prevent corrupting exported buffer.
  • Issue #23363: Fix possible overflow in itertools.permutations.
  • Issue #23364: Fix possible overflow in itertools.product.
  • Issue #23366: Fixed possible integer overflow in itertools.combinations.
  • Issue #23366: Fixed possible integer overflow in itertools.combinations.
  • Issue #23369: Fixed possible integer overflow in _json.encode_basestring_ascii.
  • Issue #23353: Fix the exception handling of generators in PyEval_EvalFrameEx(). At entry, save or swap the exception state even if PyEval_EvalFrameEx() is called with throwflag=0. At exit, the exception state is now always restored or swapped, not only if why is WHY_YIELD or WHY_RETURN. Patch co-written with Antoine Pitrou.
  • Issue #18518: timeit now rejects statements which can’t be compiled outside a function or a loop (e.g. “return” or “break”).
  • Issue #23094: Fixed readline with frames in Python implementation of pickle.
  • Issue #23268: Fixed bugs in the comparison of ipaddress classes.
  • Issue #21408: Removed incorrect implementations of __ne__() which didn’t returned NotImplemented if __eq__() returned NotImplemented. The default __ne__() now works correctly.
  • Issue #19996: email.feedparser.FeedParser now handles (malformed) headers with no key rather than amusing the body has started.
  • Issue #23248: Update ssl error codes from latest OpenSSL git master.
  • Issue #23098: 64-bit dev_t is now supported in the os module.
  • Issue #23250: In the http.cookies module, capitalize “HttpOnly” and “Secure” as they are written in the standard.
  • Issue #23063: In the disutils’ check command, fix parsing of reST with code or code-block directives.
  • Issue #23209, #23225: selectors.BaseSelector.close() now clears its internal reference to the selector mapping to break a reference cycle. Initial patch written by Martin Richard.
  • Issue #21356: Make ssl.RAND_egd() optional to support LibreSSL. The availability of the function is checked during the compilation. Patch written by Bernard Spil.
  • Issue #20896, #22935: The ssl.get_server_certificate() function now uses the PROTOCOL_SSLv23 protocol by default, not PROTOCOL_SSLv3, for maximum compatibility and support platforms where PROTOCOL_SSLv3 support is disabled.
  • Issue #23111: In the ftplib, make ssl.PROTOCOL_SSLv23 the default protocol version.
  • Issue #23132: Mitigate regression in speed and clarity in functools.total_ordering.
  • Issue #22585: On OpenBSD 5.6 and newer, os.urandom() now calls getentropy(), instead of reading /dev/urandom, to get pseudo-random bytes.
  • Issue #23112: Fix SimpleHTTPServer to correctly carry the query string and fragment when it redirects to add a trailing slash.
  • Issue #23093: In the io, module allow more operations to work on detached streams.
  • Issue #19104: pprint now produces evaluable output for wrapped strings.
  • Issue #23071: Added missing names to codecs.__all__. Patch by Martin Panter.
  • Issue #15513: Added a __sizeof__ implementation for pickle classes.
  • Issue #19858: pickletools.optimize() now aware of the MEMOIZE opcode, can produce more compact result and no longer produces invalid output if input data contains MEMOIZE opcodes together with PUT or BINPUT opcodes.
  • Issue #22095: Fixed HTTPConnection.set_tunnel with default port. The port value in the host header was set to “None”. Patch by Demian Brecht.
  • Issue #23016: A warning no longer produces an AttributeError when the program is run with pythonw.exe.
  • Issue #21775: shutil.copytree(): fix crash when copying to VFAT. An exception handler assumed that that OSError objects always have a ‘winerror’ attribute. That is not the case, so the exception handler itself raised AttributeError when run on Linux (and, presumably, any other non-Windows OS). Patch by Greg Ward.
  • Issue #1218234: Fix inspect.getsource() to load updated source of reloaded module. Initial patch by Berker Peksag.
  • Issue #22959: In the constructor of http.client.HTTPSConnection, prefer the context’s check_hostname attribute over the check_hostname parameter.
  • Issue #16043: Add a default limit for the amount of data xmlrpclib.gzip_decode will return. This resolves CVE-2013-1753.
  • Issue #22966: Fix __pycache__ pyc file name clobber when pyc_compile is asked to compile a source file containing multiple dots in the source file name.
  • Issue #21971: Update turtledemo doc and add module to the index.
  • Issue #21032. Fixed socket leak if HTTPConnection.getresponse() fails. Original patch by Martin Panter.
  • Issue #22960: Add a context argument to xmlrpclib.ServerProxy constructor.
  • Issue #22915: SAX parser now supports files opened with file descriptor or bytes path.
  • Issue #22609: Constructors and update methods of mapping classes in the collections module now accept the self keyword argument.
  • Issue #22788: Add context parameter to logging.handlers.HTTPHandler.
  • Issue #22921: Allow SSLContext to take the hostname parameter even if OpenSSL doesn’t support SNI.
  • Issue #22894: TestCase.subTest() would cause the test suite to be stopped when in failfast mode, even in the absence of failures.
  • Issue #22638: SSLv3 is now disabled throughout the standard library. It can still be enabled by instantiating a SSLContext manually.
  • Issue #22370: Windows detection in pathlib is now more robust.
  • Issue #22841: Reject coroutines in asyncio add_signal_handler(). Patch by Ludovic.Gasc.
  • Issue #22849: Fix possible double free in the io.TextIOWrapper constructor.
  • Issue #12728: Different Unicode characters having the same uppercase but different lowercase are now matched in case-insensitive regular expressions.
  • Issue #22821: Fixed fcntl() with integer argument on 64-bit big-endian platforms.
  • Issue #22406: Fixed the uu_codec codec incorrectly ported to 3.x. Based on patch by Martin Panter.
  • Issue #17293: uuid.getnode() now determines MAC address on AIX using netstat. Based on patch by Aivars Kalvāns.
  • Issue #22769: Fixed ttk.Treeview.tag_has() when called without arguments.
  • Issue #22417: Verify certificates by default in httplib (PEP 476).
  • Issue #22775: Fixed unpickling of http.cookies.SimpleCookie with protocol 2 and above. Patch by Tim Graham.
  • Issue #22366: urllib.request.urlopen will accept a context object (SSLContext) as an argument which will then used be for HTTPS connection. Patch by Alex Gaynor.
  • Issue #22776: Brought excluded code into the scope of a try block in SysLogHandler.emit().
  • Issue #22665: Add missing get_terminal_size and SameFileError to shutil.__all__.
  • Issue #17381: Fixed handling of case-insensitive ranges in regular expressions.
  • Issue #22410: Module level functions in the re module now cache compiled locale-dependent regular expressions taking into account the locale.
  • Issue #22759: Query methods on pathlib.Path() (exists(), is_dir(), etc.) now return False when the underlying stat call raises NotADirectoryError.
  • Issue #8876: distutils now falls back to copying files when hard linking doesn’t work. This allows use with special filesystems such as VirtualBox shared folders.
  • Issue #18853: Fixed ResourceWarning in shlex.__nain__.
  • Issue #9351: Defaults set with set_defaults on an argparse subparser are no longer ignored when also set on the parent parser.
  • Issue #21991: Make email.headerregistry’s header ‘params’ attributes be read-only (MappingProxyType). Previously the dictionary was modifiable but a new one was created on each access of the attribute.
  • Issue #22641: In asyncio, the default SSL context for client connections is now created using ssl.create_default_context(), for stronger security.
  • Issue #22435: Fix a file descriptor leak when SocketServer bind fails.
  • Issue #13096: Fixed segfault in CTypes POINTER handling of large values.
  • Issue #11694: Raise ConversionError in xdrlib as documented. Patch by Filip Gruszczyński and Claudiu Popa.
  • Issue #22462: Fix pyexpat’s creation of a dummy frame to make it appear in exception tracebacks.
  • Issue #21173: Fix len() on a WeakKeyDictionary when .clear() was called with an iterator alive.
  • Issue #11866: Eliminated race condition in the computation of names for new threads.
  • Issue #21905: Avoid RuntimeError in pickle.whichmodule() when sys.modules is mutated while iterating. Patch by Olivier Grisel.
  • Issue #22219: The zipfile module CLI now adds entries for directories (including empty directories) in ZIP file.
  • Issue #22449: In the ssl.SSLContext.load_default_certs, consult the enviromental variables SSL_CERT_DIR and SSL_CERT_FILE on Windows.
  • Issue #20076: Added non derived UTF-8 aliases to locale aliases table.
  • Issue #20079: Added locales supported in glibc 2.18 to locale alias table.
  • Issue #22396: On 32-bit AIX platform, don’t expose os.posix_fadvise() nor os.posix_fallocate() because their prototypes in system headers are wrong.
  • Issue #22517: When a io.BufferedRWPair object is deallocated, clear its weakrefs.
  • Issue #22448: Improve canceled timer handles cleanup to prevent unbound memory usage. Patch by Joshua Moore-Oliva.
  • Issue #23009: Make sure selectors.EpollSelecrtor.select() works when no FD is registered.
  • IDLE:
  • Issue #20577: Configuration of the max line length for the FormatParagraph extension has been moved from the General tab of the Idle preferences dialog to the FormatParagraph tab of the Config Extensions dialog. Patch by Tal Einat.
  • Issue #16893: Update Idle doc chapter to match current Idle and add new information.
  • Issue #3068: Add Idle extension configuration dialog to Options menu. Changes are written to HOME/.idlerc/config-extensions.cfg. Original patch by Tal Einat.
  • Issue #16233: A module browser (File : Class Browser, Alt+C) requires a editor window with a filename. When Class Browser is requested otherwise, from a shell, output window, or ‘Untitled’ editor, Idle no longer displays an error box. It now pops up an Open Module box (Alt+M). If a valid name is entered and a module is opened, a corresponding browser is also opened.
  • Issue #4832: Save As to type Python files automatically adds .py to the name you enter (even if your system does not display it). Some systems automatically add .txt when type is Text files.
  • Issue #21986: Code objects are not normally pickled by the pickle module. To match this, they are no longer pickled when running under Idle.
  • Issue #23180: Rename IDLE “Windows” menu item to “Window”. Patch by Al Sweigart.
  • Tests:
  • Issue #23392: Added tests for marshal C API that works with FILE*.
  • Issue #18982: Add tests for CLI of the calendar module.
  • Issue #19548: Added some additional checks to test_codecs to ensure that statements in the updated documentation remain accurate. Patch by Martin Panter.
  • Issue #22838: All test_re tests now work with unittest test discovery.
  • Issue #22173: Update lib2to3 tests to use unittest test discovery.
  • Issue #16000: Convert test_curses to use unittest.
  • Issue #21456: Skip two tests in test_urllib2net.py if _ssl module not present. Patch by Remi Pointel.
  • Issue #22770: Prevent some Tk segfaults on OS X when running gui tests.
  • Issue #23211: Workaround test_logging failure on some OS X 10.6 systems.
  • Issue #23345: Prevent test_ssl failures with large OpenSSL patch level values (like 0.9.8zc).
  • Build:
  • Issue #15506: Use standard PKG_PROG_PKG_CONFIG autoconf macro in the configure script.
  • Issue #22935: Allow the ssl module to be compiled if openssl doesn’t support SSL 3.
  • Issue #16537: Check whether self.extensions is empty in setup.py. Patch by Jonathan Hosmer.
  • Issue #18096: Fix library order returned by python-config.
  • Issue #17219: Add library build dir for Python extension cross-builds.
  • Issue #17128: Use private version of OpenSSL for 3.4.3 OS X 10.5+ installer.
  • C API:
  • Issue #22079: PyType_Ready() now checks that statically allocated type has no dynamically allocated bases.
  • Documentation:
  • Issue #19548: Update the codecs module documentation to better cover the distinction between text encodings and other codecs, together with other clarifications. Patch by Martin Panter.
  • Issue #22914: Update the Python 2/3 porting HOWTO to describe a more automated approach.
  • Issue #21514: The documentation of the json module now refers to new JSON RFC 7159 instead of obsoleted RFC 4627.
  • Tools/Demos:
  • Issue #22314: pydoc now works when the LINES environment variable is set.

New in version 3.5.0 Alpha 1 (February 9th, 2015)

  • Core and Builtins:
  • Issue #23285: PEP 475 - EINTR handling.
  • Issue #22735: Fix many edge cases (including crashes) involving custom mro() implementations.
  • Issue #22896: Avoid using PyObject_AsCharBuffer(), PyObject_AsReadBuffer() and PyObject_AsWriteBuffer().
  • Issue #21295: Revert some changes (issue #16795) to AST line numbers and column offsets that constituted a regression.
  • Issue #22986: Allow changing an object’s __class__ between a dynamic type and static type in some cases.
  • Issue #15859: PyUnicode_EncodeFSDefault(), PyUnicode_EncodeMBCS() and PyUnicode_EncodeCodePage() now raise an exception if the object is not an Unicode object. For PyUnicode_EncodeFSDefault(), it was already the case on platforms other than Windows. Patch written by Campbell Barton.
  • Issue #21408: The default __ne__() now returns NotImplemented if __eq__() returned NotImplemented. Original patch by Martin Panter.
  • Issue #23321: Fixed a crash in str.decode() when error handler returned replacment string longer than mailformed input data.
  • Issue #22286: The “backslashreplace” error handlers now works with decoding and translating.
  • Issue #23253: Delay-load ShellExecute[AW] in os.startfile for reduced startup overhead on Windows.
  • Issue #22038: pyatomic.h now uses stdatomic.h or GCC built-in functions for atomic memory access if available. Patch written by Vitor de Lima and Gustavo Temple.
  • Issue #20284: %-interpolation (aka printf) formatting added for bytes and bytearray.
  • Issue #23048: Fix jumping out of an infinite while loop in the pdb.
  • Issue #20335: bytes constructor now raises TypeError when encoding or errors is specified with non-string argument. Based on patch by Renaud Blanch.
  • Issue #22834: If the current working directory ends up being set to a non-existent directory then import will no longer raise FileNotFoundError.
  • Issue #22869: Move the interpreter startup & shutdown code to a new dedicated pylifecycle.c module
  • Issue #22847: Improve method cache efficiency.
  • Issue #22335: Fix crash when trying to enlarge a bytearray to 0x7fffffff bytes on a 32-bit platform.
  • Issue #22653: Fix an assertion failure in debug mode when doing a reentrant dict insertion in debug mode.
  • Issue #22643: Fix integer overflow in Unicode case operations (upper, lower, title, swapcase, casefold).
  • Issue #17636: Circular imports involving relative imports are now supported.
  • Issue #22604: Fix assertion error in debug mode when dividing a complex number by (nan+0j).
  • Issue #21052: Do not raise ImportWarning when sys.path_hooks or sys.meta_path are set to None.
  • Issue #16518: Use ‘bytes-like object required’ in error messages that previously used the far more cryptic “‘x’ does not support the buffer protocol.
  • Issue #22470: Fixed integer overflow issues in “backslashreplace”, “xmlcharrefreplace”, and “surrogatepass” error handlers.
  • Issue #22540: speed up PyObject_IsInstance and PyObject_IsSubclass in the common case that the second argument has metaclass type.
  • Issue #18711: Add a new PyErr_FormatV function, similar to PyErr_Format but accepting a va_list argument.
  • Issue #22520: Fix overflow checking when generating the repr of a unicode object.
  • Issue #22519: Fix overflow checking in PyBytes_Repr.
  • Issue #22518: Fix integer overflow issues in latin-1 encoding.
  • Issue #16324: _charset parameter of MIMEText now also accepts email.charset.Charset instances. Initial patch by Claude Paroz.
  • Issue #1764286: Fix inspect.getsource() to support decorated functions. Patch by Claudiu Popa.
  • Issue #18554: os.__all__ includes posix functions.
  • Issue #21391: Use os.path.abspath in the shutil module.
  • Issue #11471: avoid generating a JUMP_FORWARD instruction at the end of an if-block if there is no else-clause. Original patch by Eugene Toder.
  • Issue #22215: Now ValueError is raised instead of TypeError when str or bytes argument contains not permitted null character or byte.
  • Issue #22258: Fix the internal function set_inheritable() on Illumos. This platform exposes the function ioctl(FIOCLEX), but calling it fails with errno is ENOTTY: “Inappropriate ioctl for device”. set_inheritable() now falls back to the slower fcntl() (F_GETFD and then F_SETFD).
  • Issue #21389: Displaying the __qualname__ of the underlying function in the repr of a bound method.
  • Issue #22206: Using pthread, PyThread_create_key() now sets errno to ENOMEM and returns -1 (error) on integer overflow.
  • Issue #20184: Argument Clinic based signature introspection added for 30 of the builtin functions.
  • Issue #22116: C functions and methods (of the ‘builtin_function_or_method’ type) can now be weakref’ed. Patch by Wei Wu.
  • Issue #22077: Improve index error messages for bytearrays, bytes, lists, and tuples by adding ‘or slices’. Added ‘, not 0. Patch by Demian Brecht.
  • Issue #15381: Optimized io.BytesIO to make less allocations and copyings.
  • Issue #22818: Splitting on a pattern that could match an empty string now raises a warning. Patterns that can only match empty strings are now rejected.
  • Issue #23099: Closing io.BytesIO with exported buffer is rejected now to prevent corrupting exported buffer.
  • Issue #23326: Removed __ne__ implementations. Since fixing default __ne__ implementation in issue #21408 they are redundant.
  • Issue #23363: Fix possible overflow in itertools.permutations.
  • Issue #23364: Fix possible overflow in itertools.product.
  • Issue #23366: Fixed possible integer overflow in itertools.combinations.
  • Issue #23366: Fixed possible integer overflow in itertools.combinations.
  • Issue #23369: Fixed possible integer overflow in _json.encode_basestring_ascii.
  • Issue #23353: Fix the exception handling of generators in PyEval_EvalFrameEx(). At entry, save or swap the exception state even if PyEval_EvalFrameEx() is called with throwflag=0. At exit, the exception state is now always restored or swapped, not only if why is WHY_YIELD or WHY_RETURN. Patch co-written with Antoine Pitrou.
  • Issue #14099: Restored support of writing ZIP files to tellable but non-seekable streams.
  • Issue #14099: Writing to ZipFile and reading multiple ZipExtFiles is threadsafe now.
  • Issue #19361: JSON decoder now raises JSONDecodeError instead of ValueError.
  • Issue #18518: timeit now rejects statements which can’t be compiled outside a function or a loop (e.g. “return” or “break”).
  • Issue #23094: Fixed readline with frames in Python implementation of pickle.
  • Issue #23268: Fixed bugs in the comparison of ipaddress classes.
  • Issue #21408: Removed incorrect implementations of __ne__() which didn’t returned NotImplemented if __eq__() returned NotImplemented. The default __ne__() now works correctly.
  • Issue #19996: email.feedparser.FeedParser now handles (malformed) headers with no key rather than amusing the body has started.
  • Issue #20188: Support Application-Layer Protocol Negotiation (ALPN) in the ssl module.
  • Issue #23133: Pickling of ipaddress objects now produces more compact and portable representation.
  • Issue #23248: Update ssl error codes from latest OpenSSL git master.
  • Issue #23266: Much faster implementation of ipaddress.collapse_addresses() when there are many non-consecutive addresses.
  • Issue #23098: 64-bit dev_t is now supported in the os module.
  • Issue #21817: When an exception is raised in a task submitted to a ProcessPoolExecutor, the remote traceback is now displayed in the parent process. Patch by Claudiu Popa.
  • Issue #15955: Add an option to limit output size when decompressing LZMA data. Patch by Nikolaus Rath and Martin Panter.
  • Issue #23250: In the http.cookies module, capitalize “HttpOnly” and “Secure” as they are written in the standard.
  • Issue #23063: In the disutils’ check command, fix parsing of reST with code or code-block directives.
  • Issue #23209, #23225: selectors.BaseSelector.get_key() now raises a RuntimeError if the selector is closed. And selectors.BaseSelector.close() now clears its internal reference to the selector mapping to break a reference cycle. Initial patch written by Martin Richard.
  • Issue #19777: Provide a home() classmethod on Path objects. Contributed by Victor Salgado and Mayank Tripathi.
  • Issue #23206: Make json.dumps(..., ensure_ascii=False) as fast as the default case of ensure_ascii=True. Patch by Naoki Inada.
  • Issue #23185: Add math.inf and math.nan constants.
  • Issue #23186: Add ssl.SSLObject.shared_ciphers() and ssl.SSLSocket.shared_ciphers() to fetch the client’s list ciphers sent at handshake.
  • Issue #23143: Remove compatibility with OpenSSLs older than 0.9.8.
  • Issue #23132: Improve performance and introspection support of comparison methods created by functool.total_ordering.
  • Issue #19776: Add a expanduser() method on Path objects.
  • Issue #23112: Fix SimpleHTTPServer to correctly carry the query string and fragment when it redirects to add a trailing slash.
  • Issue #21793: Added http.HTTPStatus enums (i.e. HTTPStatus.OK, HTTPStatus.NOT_FOUND). Patch by Demian Brecht.
  • Issue #23093: In the io, module allow more operations to work on detached streams.
  • Issue #23111: In the ftplib, make ssl.PROTOCOL_SSLv23 the default protocol version.
  • Issue #22585: On OpenBSD 5.6 and newer, os.urandom() now calls getentropy(), instead of reading /dev/urandom, to get pseudo-random bytes.
  • Issue #19104: pprint now produces evaluable output for wrapped strings.
  • Issue #23071: Added missing names to codecs.__all__. Patch by Martin Panter.
  • Issue #22783: Pickling now uses the NEWOBJ opcode instead of the NEWOBJ_EX opcode if possible.
  • Issue #15513: Added a __sizeof__ implementation for pickle classes.
  • Issue #19858: pickletools.optimize() now aware of the MEMOIZE opcode, can produce more compact result and no longer produces invalid output if input data contains MEMOIZE opcodes together with PUT or BINPUT opcodes.
  • Issue #22095: Fixed HTTPConnection.set_tunnel with default port. The port value in the host header was set to “None”. Patch by Demian Brecht.
  • Issue #23016: A warning no longer produces an AttributeError when the program is run with pythonw.exe.
  • Issue #21775: shutil.copytree(): fix crash when copying to VFAT. An exception handler assumed that that OSError objects always have a ‘winerror’ attribute. That is not the case, so the exception handler itself raised AttributeError when run on Linux (and, presumably, any other non-Windows OS). Patch by Greg Ward.
  • Issue #1218234: Fix inspect.getsource() to load updated source of reloaded module. Initial patch by Berker Peksag.
  • Issue #21740: Support wrapped callables in doctest. Patch by Claudiu Popa.
  • Issue #23009: Make sure selectors.EpollSelecrtor.select() works when no FD is registered.
  • Issue #22959: In the constructor of http.client.HTTPSConnection, prefer the context’s check_hostname attribute over the check_hostname parameter.
  • Issue #22696: Add function sys.is_finalizing() to know about interpreter shutdown.
  • Issue #16043: Add a default limit for the amount of data xmlrpclib.gzip_decode will return. This resolves CVE-2013-1753.
  • Issue #14099: ZipFile.open() no longer reopen the underlying file. Objects returned by ZipFile.open() can now operate independently of the ZipFile even if the ZipFile was created by passing in a file-like object as the first argument to the constructor.
  • Issue #22966: Fix __pycache__ pyc file name clobber when pyc_compile is asked to compile a source file containing multiple dots in the source file name.
  • Issue #21971: Update turtledemo doc and add module to the index.
  • Issue #21032. Fixed socket leak if HTTPConnection.getresponse() fails. Original patch by Martin Panter.
  • Issue #22407: Deprecated the use of re.LOCALE flag with str patterns or re.ASCII. It was newer worked.
  • Issue #22902: The “ip” command is now used on Linux to determine MAC address in uuid.getnode(). Pach by Bruno Cauet.
  • Issue #22960: Add a context argument to xmlrpclib.ServerProxy constructor.
  • Issue #22389: Add contextlib.redirect_stderr().
  • Issue #21356: Make ssl.RAND_egd() optional to support LibreSSL. The availability of the function is checked during the compilation. Patch written by Bernard Spil.
  • Issue #22915: SAX parser now supports files opened with file descriptor or bytes path.
  • Issue #22609: Constructors and update methods of mapping classes in the collections module now accept the self keyword argument.
  • Issue #22940: Add readline.append_history_file.
  • Issue #19676: Added the “namereplace” error handler.
  • Issue #22788: Add context parameter to logging.handlers.HTTPHandler.
  • Issue #22921: Allow SSLContext to take the hostname parameter even if OpenSSL doesn’t support SNI.
  • Issue #22894: TestCase.subTest() would cause the test suite to be stopped when in failfast mode, even in the absence of failures.
  • Issue #22796: HTTP cookie parsing is now stricter, in order to protect against potential injection attacks.
  • Issue #22370: Windows detection in pathlib is now more robust.
  • Issue #22841: Reject coroutines in asyncio add_signal_handler(). Patch by Ludovic.Gasc.
  • Issue #19494: Added urllib.request.HTTPBasicPriorAuthHandler. Patch by Matej Cepl.
  • Issue #22578: Added attributes to the re.error class.
  • Issue #22849: Fix possible double free in the io.TextIOWrapper constructor.
  • Issue #12728: Different Unicode characters having the same uppercase but different lowercase are now matched in case-insensitive regular expressions.
  • Issue #22821: Fixed fcntl() with integer argument on 64-bit big-endian platforms.
  • Issue #21650: Add an --sort-keys option to json.tool CLI.
  • Issue #22824: Updated reprlib output format for sets to use set literals. Patch contributed by Berker Peksag.
  • Issue #22824: Updated reprlib output format for arrays to display empty arrays without an unnecessary empty list. Suggested by Serhiy Storchaka.
  • Issue #22406: Fixed the uu_codec codec incorrectly ported to 3.x. Based on patch by Martin Panter.
  • Issue #17293: uuid.getnode() now determines MAC address on AIX using netstat. Based on patch by Aivars Kalvāns.
  • Issue #22769: Fixed ttk.Treeview.tag_has() when called without arguments.
  • Issue #22417: Verify certificates by default in httplib (PEP 476).
  • Issue #22775: Fixed unpickling of http.cookies.SimpleCookie with protocol 2 and above. Patch by Tim Graham.
  • Issue #22776: Brought excluded code into the scope of a try block in SysLogHandler.emit().
  • Issue #22665: Add missing get_terminal_size and SameFileError to shutil.__all__.
  • Issue #6623: Remove deprecated Netrc class in the ftplib module. Patch by Matt Chaput.
  • Issue #17381: Fixed handling of case-insensitive ranges in regular expressions.
  • Issue #22410: Module level functions in the re module now cache compiled locale-dependent regular expressions taking into account the locale.
  • Issue #22759: Query methods on pathlib.Path() (exists(), is_dir(), etc.) now return False when the underlying stat call raises NotADirectoryError.
  • Issue #8876: distutils now falls back to copying files when hard linking doesn’t work. This allows use with special filesystems such as VirtualBox shared folders.
  • Issue #22217: Implemented reprs of classes in the zipfile module.
  • Issue #22457: Honour load_tests in the start_dir of discovery.
  • Issue #18216: gettext now raises an error when a .mo file has an unsupported major version number. Patch by Aaron Hill.
  • Issue #13918: Provide a locale.delocalize() function which can remove locale-specific number formatting from a string representing a number, without then converting it to a specific type. Patch by Cédric Krier.
  • Issue #22676: Make the pickling of global objects which don’t have a __module__ attribute less slow.
  • Issue #18853: Fixed ResourceWarning in shlex.__nain__.
  • Issue #9351: Defaults set with set_defaults on an argparse subparser are no longer ignored when also set on the parent parser.
  • Issue #7559: unittest test loading ImportErrors are reported as import errors with their import exception rather than as attribute errors after the import has already failed.
  • Issue #19746: Make it possible to examine the errors from unittest discovery without executing the test suite. The new errors attribute on TestLoader exposes these non-fatal errors encountered during discovery.
  • Issue #21991: Make email.headerregistry’s header ‘params’ attributes be read-only (MappingProxyType). Previously the dictionary was modifiable but a new one was created on each access of the attribute.
  • Issue #22638: SSLv3 is now disabled throughout the standard library. It can still be enabled by instantiating a SSLContext manually.
  • Issue #22641: In asyncio, the default SSL context for client connections is now created using ssl.create_default_context(), for stronger security.
  • Issue #17401: Include closefd in io.FileIO repr.
  • Issue #21338: Add silent mode for compileall. quiet parameters of compile_{dir, file, path} functions now have a multilevel value. Also, -q option of the CLI now have a multilevel value. Patch by Thomas Kluyver.
  • Issue #20152: Convert the array and cmath modules to Argument Clinic.
  • Issue #18643: Add socket.socketpair() on Windows.
  • Issue #22435: Fix a file descriptor leak when SocketServer bind fails.
  • Issue #13096: Fixed segfault in CTypes POINTER handling of large values.
  • Issue #11694: Raise ConversionError in xdrlib as documented. Patch by Filip Gruszczyński and Claudiu Popa.
  • Issue #19380: Optimized parsing of regular expressions.
  • Issue #1519638: Now unmatched groups are replaced with empty strings in re.sub() and re.subn().
  • Issue #18615: sndhdr.what/whathdr now return a namedtuple.
  • Issue #22462: Fix pyexpat’s creation of a dummy frame to make it appear in exception tracebacks.
  • Issue #21965: Add support for in-memory SSL to the ssl module. Patch by Geert Jansen.
  • Issue #21173: Fix len() on a WeakKeyDictionary when .clear() was called with an iterator alive.
  • Issue #11866: Eliminated race condition in the computation of names for new threads.
  • Issue #21905: Avoid RuntimeError in pickle.whichmodule() when sys.modules is mutated while iterating. Patch by Olivier Grisel.
  • Issue #11271: concurrent.futures.Executor.map() now takes a chunksize argument to allow batching of tasks in child processes and improve performance of ProcessPoolExecutor. Patch by Dan O’Reilly.
  • Issue #21883: os.path.join() and os.path.relpath() now raise a TypeError with more helpful error message for unsupported or mismatched types of arguments.
  • Issue #22219: The zipfile module CLI now adds entries for directories (including empty directories) in ZIP file.
  • Issue #22449: In the ssl.SSLContext.load_default_certs, consult the enviromental variables SSL_CERT_DIR and SSL_CERT_FILE on Windows.
  • Issue #22508: The email.__version__ variable has been removed; the email code is no longer shipped separately from the stdlib, and __version__ hasn’t been updated in several releases.
  • Issue #20076: Added non derived UTF-8 aliases to locale aliases table.
  • Issue #20079: Added locales supported in glibc 2.18 to locale alias table.
  • Issue #20218: Added convenience methods read_text/write_text and read_bytes/ write_bytes to pathlib.Path objects.
  • Issue #22437: Number of capturing groups in regular expression is no longer limited by 100.
  • Issue #17442: InteractiveInterpreter now displays the full chained traceback in its showtraceback method, to match the built in interactive interpreter.
  • Issue #23392: Added tests for marshal C API that works with FILE*.
  • Issue #10510: distutils register and upload methods now use HTML standards compliant CRLF line endings.
  • Issue #9850: Fixed macpath.join() for empty first component. Patch by Oleg Oshmyan.
  • Issue #5309: distutils’ build and build_ext commands now accept a -j option to enable parallel building of extension modules.
  • Issue #22448: Improve canceled timer handles cleanup to prevent unbound memory usage. Patch by Joshua Moore-Oliva.
  • Issue #22427: TemporaryDirectory no longer attempts to clean up twice when used in the with statement in generator.
  • Issue #22362: Forbidden ambiguous octal escapes out of range 0-0o377 in regular expressions.
  • Issue #20912: Now directories added to ZIP file have correct Unix and MS-DOS directory attributes.
  • Issue #21866: ZipFile.close() no longer writes ZIP64 central directory records if allowZip64 is false.
  • Issue #22278: Fix urljoin problem with relative urls, a regression observed after changes to issue22118 were submitted.
  • Issue #22415: Fixed debugging output of the GROUPREF_EXISTS opcode in the re module. Removed trailing spaces in debugging output.
  • Issue #22423: Unhandled exception in thread no longer causes unhandled AttributeError when sys.stderr is None.
  • Issue #21332: Ensure that bufsize=1 in subprocess.Popen() selects line buffering, rather than block buffering. Patch by Akira Li.
  • Issue #21091: Fix API bug: email.message.EmailMessage.is_attachment is now a method.
  • Issue #21079: Fix email.message.EmailMessage.is_attachment to return the correct result when the header has parameters as well as a value.
  • Issue #22247: Add NNTPError to nntplib.__all__.
  • Issue #22366: urllib.request.urlopen will accept a context object (SSLContext) as an argument which will then used be for HTTPS connection. Patch by Alex Gaynor.
  • Issue #4180: The warnings registries are now reset when the filters are modified.
  • Issue #22419: Limit the length of incoming HTTP request in wsgiref server to 65536 bytes and send a 414 error code for higher lengths. Patch contributed by Devin Cook.
  • Lax cookie parsing in http.cookies could be a security issue when combined with non-standard cookie handling in some Web browsers. Reported by Sergey Bobrov.
  • Issue #20537: logging methods now accept an exception instance as well as a Boolean value or exception tuple. Thanks to Yury Selivanov for the patch.
  • Issue #22384: An exception in Tkinter callback no longer crashes the program when it is run with pythonw.exe.
  • Issue #22168: Prevent turtle AttributeError with non-default Canvas on OS X.
  • Issue #21147: sqlite3 now raises an exception if the request contains a null character instead of truncate it. Based on patch by Victor Stinner.
  • Issue #13968: The glob module now supports recursive search in subdirectories using the “**” pattern.
  • Issue #21951: Fixed a crash in Tkinter on AIX when called Tcl command with empty string or tuple argument.
  • Issue #21951: Tkinter now most likely raises MemoryError instead of crash if the memory allocation fails.
  • Issue #22338: Fix a crash in the json module on memory allocation failure.
  • Issue #12410: imaplib.IMAP4 now supports the context management protocol. Original patch by Tarek Ziadé.
  • Issue #21270: We now override tuple methods in mock.call objects so that they can be used as normal call attributes.
  • Issue #16662: load_tests() is now unconditionally run when it is present in a package’s __init__.py. TestLoader.loadTestsFromModule() still accepts use_load_tests, but it is deprecated and ignored. A new keyword-only attribute pattern is added and documented. Patch given by Robert Collins, tweaked by Barry Warsaw.
  • Issue #22226: First letter no longer is stripped from the “status” key in the result of Treeview.heading().
  • Issue #19524: Fixed resource leak in the HTTP connection when an invalid response is received. Patch by Martin Panter.
  • Issue #20421: Add a .version() method to SSL sockets exposing the actual protocol version in use.
  • Issue #19546: configparser exceptions no longer expose implementation details. Chained KeyErrors are removed, which leads to cleaner tracebacks. Patch by Claudiu Popa.
  • Issue #22051: turtledemo no longer reloads examples to re-run them. Initialization of variables and gui setup should be done in main(), which is called each time a demo is run, but not on import.
  • Issue #21933: Turtledemo users can change the code font size with a menu selection or control(command) ‘-‘ or ‘+’ or control-mousewheel. Original patch by Lita Cho.
  • Issue #21597: The separator between the turtledemo text pane and the drawing canvas can now be grabbed and dragged with a mouse. The code text pane can be widened to easily view or copy the full width of the text. The canvas can be widened on small screens. Original patches by Jan Kanis and Lita Cho.
  • Issue #18132: Turtledemo buttons no longer disappear when the window is shrunk. Original patches by Jan Kanis and Lita Cho.
  • Issue #22043: time.monotonic() is now always available. threading.Lock.acquire(), threading.RLock.acquire() and socket operations now use a monotonic clock, instead of the system clock, when a timeout is used.
  • Issue #21527: Add a default number of workers to ThreadPoolExecutor equal to 5 times the number of CPUs. Patch by Claudiu Popa.
  • Issue #22216: smtplib now resets its state more completely after a quit. The most obvious consequence of the previous behavior was a STARTTLS failure during a connect/starttls/quit/connect/starttls sequence.
  • Issue #22098: ctypes’ BigEndianStructure and LittleEndianStructure now define an empty __slots__ so that subclasses don’t always get an instance dict. Patch by Claudiu Popa.
  • Issue #22185: Fix an occasional RuntimeError in threading.Condition.wait() caused by mutation of the waiters queue without holding the lock. Patch by Doug Zongker.
  • Issue #22287: On UNIX, _PyTime_gettimeofday() now uses clock_gettime(CLOCK_REALTIME) if available. As a side effect, Python now depends on the librt library on Solaris and on Linux (only with glibc older than 2.17).
  • Issue #22182: Use e.args to unpack exceptions correctly in distutils.file_util.move_file. Patch by Claudiu Popa.
  • The webbrowser module now uses subprocess’s start_new_session=True rather than a potentially risky preexec_fn=os.setsid call.
  • Issue #22042: signal.set_wakeup_fd(fd) now raises an exception if the file descriptor is in blocking mode.
  • Issue #16808: inspect.stack() now returns a named tuple instead of a tuple. Patch by Daniel Shahaf.
  • Issue #22236: Fixed Tkinter images copying operations in NoDefaultRoot mode.
  • Issue #2527: Add a globals argument to timeit functions, in order to override the globals namespace in which the timed code is executed. Patch by Ben Roberts.
  • Issue #22118: Switch urllib.parse to use RFC 3986 semantics for the resolution of relative URLs, rather than RFCs 1808 and 2396. Patch by Demian Brecht.
  • Issue #21549: Added the “members” parameter to TarFile.list().
  • Issue #19628: Allow compileall recursion depth to be specified with a -r option.
  • Issue #15696: Add a __sizeof__ implementation for mmap objects on Windows.
  • Issue #22068: Avoided reference loops with Variables and Fonts in Tkinter.
  • Issue #22165: SimpleHTTPRequestHandler now supports undecodable file names.
  • Issue #15381: Optimized line reading in io.BytesIO.
  • Issue #8797: Raise HTTPError on failed Basic Authentication immediately. Initial patch by Sam Bull.
  • Issue #20729: Restored the use of lazy iterkeys()/itervalues()/iteritems() in the mailbox module.
  • Issue #21448: Changed FeedParser feed() to avoid O(N**2) behavior when parsing long line. Original patch by Raymond Hettinger.
  • Issue #22184: The functools LRU Cache decorator factory now gives an earlier and clearer error message when the user forgets the required parameters.
  • Issue #17923: glob() patterns ending with a slash no longer match non-dirs on AIX. Based on patch by Delhallt.
  • Issue #21725: Added support for RFC 6531 (SMTPUTF8) in smtpd.
  • Issue #22176: Update the ctypes module’s libffi to v3.1. This release adds support for the Linux AArch64 and POWERPC ELF ABIv2 little endian architectures.
  • Issue #5411: Added support for the “xztar” format in the shutil module.
  • Issue #21121: Don’t force 3rd party C extensions to be built with -Werror=declaration-after-statement.
  • Issue #21975: Fixed crash when using uninitialized sqlite3.Row (in particular when unpickling pickled sqlite3.Row). sqlite3.Row is now initialized in the __new__() method.
  • Issue #20170: Convert posixmodule to use Argument Clinic.
  • Issue #21539: Add a exists_ok argument to Pathlib.mkdir() to mimic mkdir -p and os.makedirs() functionality. When true, ignore FileExistsErrors. Patch by Berker Peksag.
  • Issue #22127: Bypass IDNA for pure-ASCII host names in the socket module (in particular for numeric IPs).
  • Issue #21047: set the default value for the convert_charrefs argument of HTMLParser to True. Patch by Berker Peksag.
  • Add an __all__ to html.entities.
  • Issue #15114: the strict mode and argument of HTMLParser, HTMLParser.error, and the HTMLParserError exception have been removed.
  • Issue #22085: Dropped support of Tk 8.3 in Tkinter.
  • Issue #21580: Now Tkinter correctly handles bytes arguments passed to Tk. In particular this allows to initialize images from binary data.
  • Issue #22003: When initialized from a bytes object, io.BytesIO() now defers making a copy until it is mutated, improving performance and memory use on some use cases. Patch by David Wilson.
  • Issue #22018: On Windows, signal.set_wakeup_fd() now also supports sockets. A side effect is that Python depends to the WinSock library.
  • Issue #22054: Add os.get_blocking() and os.set_blocking() functions to get and set the blocking mode of a file descriptor (False if the O_NONBLOCK flag is set, True otherwise). These functions are not available on Windows.
  • Issue #17172: Make turtledemo start as active on OS X even when run with subprocess. Patch by Lita Cho.
  • Issue #21704: Fix build error for _multiprocessing when semaphores are not available. Patch by Arfrever Frehtes Taifersar Arahesis.
  • Issue #20173: Convert sha1, sha256, sha512 and md5 to ArgumentClinic. Patch by Vajrasky Kok.
  • Fix repr(_socket.socket) on Windows 64-bit: don’t fail with OverflowError on closed socket. repr(socket.socket) already works fine.
  • Issue #22033: Reprs of most Python implemened classes now contain actual class name instead of hardcoded one.
  • Issue #21947: The dis module can now disassemble generator-iterator objects based on their gi_code attribute. Patch by Clement Rouault.
  • Issue #16133: The asynchat.async_chat.handle_read() method now ignores BlockingIOError exceptions.
  • Issue #22044: Fixed premature DECREF in call_tzinfo_method. Patch by Tom Flanagan.
  • Issue #19884: readline: Disable the meta modifier key if stdout is not a terminal to not write the ANSI sequence “033[1034h” into stdout. This sequence is used on some terminal (ex: TERM=xterm-256color”) to enable support of 8 bit characters.
  • Issue #4350: Removed a number of out-of-dated and non-working for a long time Tkinter methods.
  • Issue #6167: Scrollbar.activate() now returns the name of active element if the argument is not specified. Scrollbar.set() now always accepts only 2 arguments.
  • Issue #15275: Clean up and speed up the ntpath module.
  • Issue #21888: plistlib’s load() and loads() now work if the fmt parameter is specified.
  • Issue #22032: __qualname__ instead of __name__ is now always used to format fully qualified class names of Python implemented classes.
  • Issue #22031: Reprs now always use hexadecimal format with the “0x” prefix when contain an id in form ” at 0x...”.
  • Issue #22018: signal.set_wakeup_fd() now raises an OSError instead of a ValueError on fstat() failure.
  • Issue #21044: tarfile.open() now handles fileobj with an integer ‘name’ attribute. Based on patch by Antoine Pietri.
  • Issue #21966: Respect -q command-line option when code module is ran.
  • Issue #19076: Don’t pass the redundant ‘file’ argument to self.error().
  • Issue #16382: Improve exception message of warnings.warn() for bad category. Initial patch by Phil Elson.
  • Issue #21932: os.read() now uses a Py_ssize_t() type instead of int for the size to support reading more than 2 GB at once. On Windows, the size is truncted to INT_MAX. As any call to os.read(), the OS may read less bytes than the number of requested bytes.
  • Issue #21942: Fixed source file viewing in pydoc’s server mode on Windows.
  • Issue #11259: asynchat.async_chat().set_terminator() now raises a ValueError if the number of received bytes is negative.
  • Issue #12523: asynchat.async_chat.push() now raises a TypeError if it doesn’t get a bytes string
  • Issue #21707: Add missing kwonlyargcount argument to ModuleFinder.replace_paths_in_code().
  • Issue #20639: calling Path.with_suffix(‘’) allows removing the suffix again. Patch by July Tikhonov.
  • Issue #21714: Disallow the construction of invalid paths using Path.with_name(). Original patch by Antony Lee.
  • Issue #15014: Added ‘auth’ method to smtplib to make implementing auth mechanisms simpler, and used it internally in the login method.
  • Issue #21151: Fixed a segfault in the winreg module when None is passed as a REG_BINARY value to SetValueEx. Patch by John Ehresman.
  • Issue #21090: io.FileIO.readall() does not ignore I/O errors anymore. Before, it ignored I/O errors if at least the first C call read() succeed.
  • Issue #5800: headers parameter of wsgiref.headers.Headers is now optional. Initial patch by Pablo Torres Navarrete and SilentGhost.
  • Issue #21781: ssl.RAND_add() now supports strings longer than 2 GB.
  • Issue #21679: Prevent extraneous fstat() calls during open(). Patch by Bohuslav Kabrda.
  • Issue #21863: cProfile now displays the module name of C extension functions, in addition to their own name.
  • Issue #11453: asyncore: emit a ResourceWarning when an unclosed file_wrapper object is destroyed. The destructor now closes the file if needed. The close() method can now be called twice: the second call does nothing.
  • Issue #21858: Better handling of Python exceptions in the sqlite3 module.
  • Issue #21476: Make sure the email.parser.BytesParser TextIOWrapper is discarded after parsing, so the input file isn’t unexpectedly closed.
  • Issue #20295: imghdr now recognizes OpenEXR format images.
  • Issue #21729: Used the “with” statement in the dbm.dumb module to ensure files closing. Patch by Claudiu Popa.
  • Issue #21491: socketserver: Fix a race condition in child processes reaping.
  • Issue #21719: Added the st_file_attributes field to os.stat_result on Windows.
  • Issue #21832: Require named tuple inputs to be exact strings.
  • Issue #21722: The distutils “upload” command now exits with a non-zero return code when uploading fails. Patch by Martin Dengler.
  • Issue #21723: asyncio.Queue: support any type of number (ex: float) for the maximum size. Patch written by Vajrasky Kok.
  • Issue #21711: support for “site-python” directories has now been removed from the site module (it was deprecated in 3.4).
  • Issue #17552: new socket.sendfile() method allowing to send a file over a socket by using high-performance os.sendfile() on UNIX. Patch by Giampaolo Rodola’.
  • Issue #18039: dbm.dump.open() now always creates a new database when the flag has the value ‘n’. Patch by Claudiu Popa.
  • Issue #21326: Add a new is_closed() method to asyncio.BaseEventLoop. run_forever() and run_until_complete() methods of asyncio.BaseEventLoop now raise an exception if the event loop was closed.
  • Issue #21766: Prevent a security hole in CGIHTTPServer by URL unquoting paths before checking for a CGI script at that path.
  • Issue #21310: Fixed possible resource leak in failed open().
  • Issue #21256: Printout of keyword args should be in deterministic order in a mock function call. This will help to write better doctests.
  • Issue #21677: Fixed chaining nonnormalized exceptions in io close() methods.
  • Issue #11709: Fix the pydoc.help function to not fail when sys.stdin is not a valid file.
  • Issue #21515: tempfile.TemporaryFile now uses os.O_TMPFILE flag is available.
  • Issue #13223: Fix pydoc.writedoc so that the HTML documentation for methods that use ‘self’ in the example code is generated correctly.
  • Issue #21463: In urllib.request, fix pruning of the FTP cache.
  • Issue #21618: The subprocess module could fail to close open fds that were inherited by the calling process and already higher than POSIX resource limits would otherwise allow. On systems with a functioning /proc/self/fd or /dev/fd interface the max is now ignored and all fds are closed.
  • Issue #20383: Introduce importlib.util.module_from_spec() as the preferred way to create a new module.
  • Issue #21552: Fixed possible integer overflow of too long string lengths in the tkinter module on 64-bit platforms.
  • Issue #14315: The zipfile module now ignores extra fields in the central directory that are too short to be parsed instead of letting a struct.unpack error bubble up as this “bad data” appears in many real world zip files in the wild and is ignored by other zip tools.
  • Issue #13742: Added “key” and “reverse” parameters to heapq.merge(). (First draft of patch contributed by Simon Sapin.)
  • Issue #21402: tkinter.ttk now works when default root window is not set.
  • Issue #3015: _tkinter.create() now creates tkapp object with wantobject=1 by default.
  • Issue #10203: sqlite3.Row now truly supports sequence protocol. In particulr it supports reverse() and negative indices. Original patch by Claudiu Popa.
  • Issue #18807: If copying (no symlinks) specified for a venv, then the python interpreter aliases (python, python3) are now created by copying rather than symlinking.
  • Issue #20197: Added support for the WebP image type in the imghdr module. Patch by Fabrice Aneche and Claudiu Popa.
  • Issue #21513: Speedup some properties of IP addresses (IPv4Address, IPv6Address) such as .is_private or .is_multicast.
  • Issue #21137: Improve the repr for threading.Lock() and its variants by showing the “locked” or “unlocked” status. Patch by Berker Peksag.
  • Issue #21538: The plistlib module now supports loading of binary plist files when reference or offset size is not a power of two.
  • Issue #21455: Add a default backlog to socket.listen().
  • Issue #21525: Most Tkinter methods which accepted tuples now accept lists too.
  • Issue #22166: with the assistance of a new internal _codecs._forget_codec helping function, test_codecs now clears the encoding caches to avoid the appearance of a reference leak
  • Issue #22236: Tkinter tests now don’t reuse default root window. New root window is created for every test class.
  • Issue #10744: Fix PEP 3118 format strings on ctypes objects with a nontrivial shape.
  • Issue #20826: Optimize ipaddress.collapse_addresses().
  • Issue #21487: Optimize ipaddress.summarize_address_range() and ipaddress.{IPv4Network,IPv6Network}.subnets().
  • Issue #21486: Optimize parsing of netmasks in ipaddress.IPv4Network and ipaddress.IPv6Network.
  • Issue #13916: Disallowed the surrogatepass error handler for non UTF-* encodings.
  • Issue #20998: Fixed re.fullmatch() of repeated single character pattern with ignore case. Original patch by Matthew Barnett.
  • Issue #21075: fileinput.FileInput now reads bytes from standard stream if binary mode is specified. Patch by Sam Kimbrel.
  • Issue #19775: Add a samefile() method to pathlib Path objects. Initial patch by Vajrasky Kok.
  • Issue #21226: Set up modules properly in PyImport_ExecCodeModuleObject (and friends).
  • Issue #21398: Fix an unicode error in the pydoc pager when the documentation contains characters not encodable to the stdout encoding.
  • Issue #16531: ipaddress.IPv4Network and ipaddress.IPv6Network now accept an (address, netmask) tuple argument, so as to easily construct network objects from existing addresses.
  • Issue #21156: importlib.abc.InspectLoader.source_to_code() is now a staticmethod.
  • Issue #21424: Simplified and optimized heaqp.nlargest() and nmsmallest() to make fewer tuple comparisons.
  • Issue #21396: Fix TextIOWrapper(..., write_through=True) to not force a flush() on the underlying binary stream. Patch by akira.
  • Issue #18314: Unlink now removes junctions on Windows. Patch by Kim Gräsman
  • Issue #21088: Bugfix for curses.window.addch() regression in 3.4.0. In porting to Argument Clinic, the first two arguments were reversed.
  • Issue #21407: _decimal: The module now supports function signatures.
  • Issue #10650: Remove the non-standard ‘watchexp’ parameter from the Decimal.quantize() method in the Python version. It had never been present in the C version.
  • Issue #21469: Reduced the risk of false positives in robotparser by checking to make sure that robots.txt has been read or does not exist prior to returning True in can_fetch().
  • Issue #19414: Have the OrderedDict mark deleted links as unusable. This gives an early failure if the link is deleted during iteration.
  • Issue #21421: Add __slots__ to the MappingViews ABC. Patch by Josh Rosenberg.
  • Issue #21101: Eliminate double hashing in the C speed-up code for collections.Counter().
  • Issue #21321: itertools.islice() now releases the reference to the source iterator when the slice is exhausted. Patch by Anton Afanasyev.
  • Issue #21057: TextIOWrapper now allows the underlying binary stream’s read() or read1() method to return an arbitrary bytes-like object (such as a memoryview). Patch by Nikolaus Rath.
  • Issue #20951: SSLSocket.send() now raises either SSLWantReadError or SSLWantWriteError on a non-blocking socket if the operation would block. Previously, it would return 0. Patch by Nikolaus Rath.
  • Issue #13248: removed previously deprecated asyncore.dispatcher __getattr__ cheap inheritance hack.
  • Issue #9815: assertRaises now tries to clear references to local variables in the exception’s traceback.
  • Issue #19940: ssl.cert_time_to_seconds() now interprets the given time string in the UTC timezone (as specified in RFC 5280), not the local timezone.
  • Issue #13204: Calling sys.flags.__new__ would crash the interpreter, now it raises a TypeError.
  • Issue #19385: Make operations on a closed dbm.dumb database always raise the same exception.
  • Issue #21207: Detect when the os.urandom cached fd has been closed or replaced, and open it anew.
  • Issue #21291: subprocess’s Popen.wait() is now thread safe so that multiple threads may be calling wait() or poll() on a Popen instance at the same time without losing the Popen.returncode value.
  • Issue #21127: Path objects can now be instantiated from str subclass instances (such as numpy.str_).
  • Issue #15002: urllib.response object to use _TemporaryFileWrapper (and _TemporaryFileCloser) facility. Provides a better way to handle file descriptor close. Patch contributed by Christian Theune.
  • Issue #12220: mindom now raises a custom ValueError indicating it doesn’t support spaces in URIs instead of letting a ‘split’ ValueError bubble up.
  • Issue #21068: The ssl.PROTOCOL* constants are now enum members.
  • Issue #21276: posixmodule: Don’t define USE_XATTRS on KFreeBSD and the Hurd.
  • Issue #21262: New method assert_not_called for Mock. It raises AssertionError if the mock has been called.
  • Issue #21238: New keyword argument unsafe to Mock. It raises AttributeError incase of an attribute startswith assert or assret.
  • Issue #20896: ssl.get_server_certificate() now uses PROTOCOL_SSLv23, not PROTOCOL_SSLv3, for maximum compatibility.
  • Issue #21239: patch.stopall() didn’t work deterministically when the same name was patched more than once.
  • Issue #21203: Updated fileConfig and dictConfig to remove inconsistencies. Thanks to Jure Koren for the patch.
  • Issue #21222: Passing name keyword argument to mock.create_autospec now works.
  • Issue #21197: Add lib64 -> lib symlink in venvs on 64-bit non-OS X POSIX.
  • Issue #17498: Some SMTP servers disconnect after certain errors, violating strict RFC conformance. Instead of losing the error code when we issue the subsequent RSET, smtplib now returns the error code and defers raising the SMTPServerDisconnected error until the next command is issued.
  • Issue #17826: setting an iterable side_effect on a mock function created by create_autospec now works. Patch by Kushal Das.
  • Issue #7776: Fix Host: header and reconnection when using http.client.HTTPConnection.set_tunnel(). Patch by Nikolaus Rath.
  • Issue #20968: unittest.mock.MagicMock now supports division. Patch by Johannes Baiter.
  • Fix arbitrary memory access in JSONDecoder.raw_decode with a negative second parameter. Bug reported by Guido Vranken.
  • Issue #21169: getpass now handles non-ascii characters that the input stream encoding cannot encode by re-encoding using the replace error handler.
  • Issue #21171: Fixed undocumented filter API of the rot13 codec. Patch by Berker Peksag.
  • Issue #20539: Improved math.factorial error message for large positive inputs and changed exception type (OverflowError -> ValueError) for large negative inputs.
  • Issue #21172: isinstance check relaxed from dict to collections.Mapping.
  • Issue #21155: asyncio.EventLoop.create_unix_server() now raises a ValueError if path and sock are specified at the same time.
  • Issue #21136: Avoid unnecessary normalization of Fractions resulting from power and other operations. Patch by Raymond Hettinger.
  • Issue #17621: Introduce importlib.util.LazyLoader.
  • Issue #21076: signal module constants were turned into enums. Patch by Giampaolo Rodola’.
  • Issue #20636: Improved the repr of Tkinter widgets.
  • Issue #19505: The items, keys, and values views of OrderedDict now support reverse iteration using reversed().
  • Issue #21149: Improved thread-safety in logging cleanup during interpreter shutdown. Thanks to Devin Jeanpierre for the patch.
  • Issue #21058: Fix a leak of file descriptor in tempfile.NamedTemporaryFile(), close the file descriptor if io.open() fails
  • Issue #21200: Return None from pkgutil.get_loader() when __spec__ is missing.
  • Issue #21013: Enhance ssl.create_default_context() when used for server side sockets to provide better security by default.
  • Issue #20145: assertRaisesRegex and assertWarnsRegex now raise a TypeError if the second argument is not a string or compiled regex.
  • Issue #20633: Replace relative import by absolute import.
  • Issue #20980: Stop wrapping exception when using ThreadPool.
  • Issue #21082: In os.makedirs, do not set the process-wide umask. Note this changes behavior of makedirs when exist_ok=True.
  • Issue #20990: Fix issues found by pyflakes for multiprocessing.
  • Issue #21015: SSL contexts will now automatically select an elliptic curve for ECDH key exchange on OpenSSL 1.0.2 and later, and otherwise default to “prime256v1”.
  • Issue #21000: Improve the command-line interface of json.tool.
  • Issue #20995: Enhance default ciphers used by the ssl module to enable better security an prioritize perfect forward secrecy.
  • Issue #20884: Don’t assume that __file__ is defined on importlib.__init__.
  • Issue #21499: Ignore __builtins__ in several test_importlib.test_api tests.
  • Issue #20627: xmlrpc.client.ServerProxy is now a context manager.
  • Issue #19165: The formatter module now raises DeprecationWarning instead of PendingDeprecationWarning.
  • Issue #13936: Remove the ability of datetime.time instances to be considered false in boolean contexts.
  • Issue 18931: selectors module now supports /dev/poll on Solaris. Patch by Giampaolo Rodola’.
  • Issue #19977: When the LC_TYPE locale is the POSIX locale (C locale), sys.stdin and sys.stdout are now using the surrogateescape error handler, instead of the strict error handler.
  • Issue #20574: Implement incremental decoder for cp65001 code (Windows code page 65001, Microsoft UTF-8).
  • Issue #20879: Delay the initialization of encoding and decoding tables for base32, ascii85 and base85 codecs in the base64 module, and delay the initialization of the unquote_to_bytes() table of the urllib.parse module, to not waste memory if these modules are not used.
  • Issue #19157: Include the broadcast address in the usuable hosts for IPv6 in ipaddress.
  • Issue #11599: When an external command (e.g. compiler) fails, distutils now prints out the whole command line (instead of just the command name) if the environment variable DISTUTILS_DEBUG is set.
  • Issue #4931: distutils should not produce unhelpful “error: None” messages anymore. distutils.util.grok_environment_error is kept but doc-deprecated.
  • Issue #20875: Prevent possible gzip “‘read’ is not defined” NameError. Patch by Claudiu Popa.
  • Issue #11558: email.message.Message.attach now returns a more useful error message if attach is called on a message for which is_multipart is False.
  • Issue #20283: RE pattern methods now accept the string keyword parameters as documented. The pattern and source keyword parameters are left as deprecated aliases.
  • Issue #20778: Fix modulefinder to work with bytecode-only modules.
  • Issue #20791: copy.copy() now doesn’t make a copy when the input is a bytes object. Initial patch by Peter Otten.
  • Issue #19748: On AIX, time.mktime() now raises an OverflowError for year outsize range [1902; 2037].
  • Issue #19573: inspect.signature: Use enum for parameter kind constants.
  • Issue #20726: inspect.signature: Make Signature and Parameter picklable.
  • Issue #17373: Add inspect.Signature.from_callable method.
  • Issue #20378: Improve repr of inspect.Signature and inspect.Parameter.
  • Issue #20816: Fix inspect.getcallargs() to raise correct TypeError for missing keyword-only arguments. Patch by Jeremiah Lowin.
  • Issue #20817: Fix inspect.getcallargs() to fail correctly if more than 3 arguments are missing. Patch by Jeremiah Lowin.
  • Issue #6676: Ensure a meaningful exception is raised when attempting to parse more than one XML document per pyexpat xmlparser instance. (Original patches by Hirokazu Yamamoto and Amaury Forgeot d’Arc, with suggested wording by David Gutteridge)
  • Issue #21117: Fix inspect.signature to better support functools.partial. Due to the specifics of functools.partial implementation, positional-or-keyword arguments passed as keyword arguments become keyword-only.
  • Issue #20334: inspect.Signature and inspect.Parameter are now hashable. Thanks to Antony Lee for bug reports and suggestions.
  • Issue #15916: doctest.DocTestSuite returns an empty unittest.TestSuite instead of raising ValueError if it finds no tests
  • Issue #21209: Fix asyncio.tasks.CoroWrapper to workaround a bug in yield-from implementation in CPythons prior to 3.4.1.
  • asyncio: Add gi_{frame,running,code} properties to CoroWrapper (upstream issue #163).
  • Issue #21311: Avoid exception in _osx_support with non-standard compiler configurations. Patch by John Szakmeister.
  • Issue #11571: Ensure that the turtle window becomes the topmost window when launched on OS X.
  • Issue #21801: Validate that __signature__ is None or an instance of Signature.
  • Issue #21923: Prevent AttributeError in distutils.sysconfig.customize_compiler due to possible uninitialized _config_vars.
  • Issue #21323: Fix http.server to again handle scripts in CGI subdirectories, broken by the fix for security issue #19435. Patch by Zach Byrne.
  • Issue #22733: Fix ffi_prep_args not zero-extending argument values correctly on 64-bit Windows.
  • Issue #23302: Default to TCP_NODELAY=1 upon establishing an HTTPConnection. Removed use of hard-coded MSS as it’s an optimization that’s no longer needed with Nagle disabled.
  • IDLE:
  • Issue #20577: Configuration of the max line length for the FormatParagraph extension has been moved from the General tab of the Idle preferences dialog to the FormatParagraph tab of the Config Extensions dialog. Patch by Tal Einat.
  • Issue #16893: Update Idle doc chapter to match current Idle and add new information.
  • Issue #3068: Add Idle extension configuration dialog to Options menu. Changes are written to HOME/.idlerc/config-extensions.cfg. Original patch by Tal Einat.
  • Issue #16233: A module browser (File : Class Browser, Alt+C) requires a editor window with a filename. When Class Browser is requested otherwise, from a shell, output window, or ‘Untitled’ editor, Idle no longer displays an error box. It now pops up an Open Module box (Alt+M). If a valid name is entered and a module is opened, a corresponding browser is also opened.
  • Issue #4832: Save As to type Python files automatically adds .py to the name you enter (even if your system does not display it). Some systems automatically add .txt when type is Text files.
  • Issue #21986: Code objects are not normally pickled by the pickle module. To match this, they are no longer pickled when running under Idle.
  • Issue #17390: Adjust Editor window title; remove ‘Python’, move version to end.
  • Issue #14105: Idle debugger breakpoints no longer disappear when inseting or deleting lines.
  • Issue #17172: Turtledemo can now be run from Idle. Currently, the entry is on the Help menu, but it may move to Run. Patch by Ramchandra Apt and Lita Cho.
  • Issue #21765: Add support for non-ascii identifiers to HyperParser.
  • Issue #21940: Add unittest for WidgetRedirector. Initial patch by Saimadhav Heblikar.
  • Issue #18592: Add unittest for SearchDialogBase. Patch by Phil Webster.
  • Issue #21694: Add unittest for ParenMatch. Patch by Saimadhav Heblikar.
  • Issue #21686: add unittest for HyperParser. Original patch by Saimadhav Heblikar.
  • Issue #12387: Add missing upper(lower)case versions of default Windows key bindings for Idle so Caps Lock does not disable them. Patch by Roger Serwy.
  • Issue #21695: Closing a Find-in-files output window while the search is still in progress no longer closes Idle.
  • Issue #18910: Add unittest for textView. Patch by Phil Webster.
  • Issue #18292: Add unittest for AutoExpand. Patch by Saihadhav Heblikar.
  • Issue #18409: Add unittest for AutoComplete. Patch by Phil Webster.
  • Issue #21477: htest.py - Improve framework, complete set of tests. Patches by Saimadhav Heblikar
  • Issue #18104: Add idlelib/idle_test/htest.py with a few sample tests to begin consolidating and improving human-validated tests of Idle. Change other files as needed to work with htest. Running the module as __main__ runs all tests.
  • Issue #21139: Change default paragraph width to 72, the PEP 8 recommendation.
  • Issue #21284: Paragraph reformat test passes after user changes reformat width.
  • Issue #17654: Ensure IDLE menus are customized properly on OS X for non-framework builds and for all variants of Tk.
  • Issue #23180: Rename IDLE “Windows” menu item to “Window”. Patch by Al Sweigart.
  • Build:
  • Issue #15506: Use standard PKG_PROG_PKG_CONFIG autoconf macro in the configure script.
  • Issue #22935: Allow the ssl module to be compiled if openssl doesn’t support SSL 3.
  • Issue #22592: Drop support of the Borland C compiler to build Python. The distutils module still supports it to build extensions.
  • Issue #22591: Drop support of MS-DOS, especially of the DJGPP compiler (MS-DOS port of GCC).
  • Issue #16537: Check whether self.extensions is empty in setup.py. Patch by Jonathan Hosmer.
  • Issue #22359: Remove incorrect uses of recursive make. Patch by Jonas Wagner.
  • Issue #21958: Define HAVE_ROUND when building with Visual Studio 2013 and above. Patch by Zachary Turner.
  • Issue #18093: the programs that embed the CPython runtime are now in a separate “Programs” directory, rather than being kept in the Modules directory.
  • Issue #15759: “make suspicious”, “make linkcheck” and “make doctest” in Doc/ now display special message when and only when there are failures.
  • Issue #21141: The Windows build process no longer attempts to find Perl, instead relying on OpenSSL source being configured and ready to build. The PCbuild\build_ssl.py script has been re-written and re-named to PCbuild\prepare_ssl.py, and takes care of configuring OpenSSL source for both 32 and 64 bit platforms. OpenSSL sources obtained from svn.python.org will always be pre-configured and ready to build.
  • Issue #21037: Add a build option to enable AddressSanitizer support.
  • Issue #19962: The Windows build process now creates “python.bat” in the root of the source tree, which passes all arguments through to the most recently built interpreter.
  • Issue #21285: Refactor and fix curses configure check to always search in a ncursesw directory.
  • Issue #15234: For BerkelyDB and Sqlite, only add the found library and include directories if they aren’t already being searched. This avoids an explicit runtime library dependency.
  • Issue #17861: Tools/scripts/generate_opcode_h.py automatically regenerates Include/opcode.h from Lib/opcode.py if the later gets any change.
  • Issue #20644: OS X installer build support for documentation build changes in 3.4.1: assume externally supplied sphinx-build is available in /usr/bin.
  • Issue #20022: Eliminate use of deprecated bundlebuilder in OS X builds.
  • Issue #15968: Incorporated Tcl, Tk, and Tix builds into the Windows build solution.
  • Issue #17095: Fix Modules/Setup shared support.
  • Issue #21811: Anticipated fixes to support OS X versions > 10.9.
  • Issue #21166: Prevent possible segfaults and other random failures of python –generate-posix-vars in pybuilddir.txt build target.
  • Issue #18096: Fix library order returned by python-config.
  • Issue #17219: Add library build dir for Python extension cross-builds.
  • Issue #22919: Windows build updated to support VC 14.0 (Visual Studio 2015), which will be used for the official release.
  • Issue #21236: Build _msi.pyd with cabinet.lib instead of fci.lib
  • Issue #17128: Use private version of OpenSSL for OS X 10.5+ installer.
  • C API:
  • Issue #14203: Remove obsolete support for view==NULL in PyBuffer_FillInfo(), bytearray_getbuffer(), bytesiobuf_getbuffer() and array_buffer_getbuf(). All functions now raise BufferError in that case.
  • Issue #22445: PyBuffer_IsContiguous() now implements precise contiguity tests, compatible with NumPy’s NPY_RELAXED_STRIDES_CHECKING compilation flag. Previously the function reported false negatives for corner cases.
  • Issue #22079: PyType_Ready() now checks that statically allocated type has no dynamically allocated bases.
  • Issue #22453: Removed non-documented macro PyObject_REPR().
  • Issue #18395: Rename _Py_char2wchar() to Py_DecodeLocale(), rename _Py_wchar2char() to Py_EncodeLocale(), and document these functions.
  • Issue #21233: Add new C functions: PyMem_RawCalloc(), PyMem_Calloc(), PyObject_Calloc(), _PyObject_GC_Calloc(). bytes(int) is now using calloc() instead of malloc() for large objects which is faster and use less memory.
  • Issue #20942: PyImport_ImportFrozenModuleObject() no longer sets __file__ to match what importlib does; this affects _frozen_importlib as well as any module loaded using imp.init_frozen().
  • Documentation:
  • Issue #19548: Update the codecs module documentation to better cover the distinction between text encodings and other codecs, together with other clarifications. Patch by Martin Panter.
  • Issue #22394: Doc/Makefile now supports make venv PYTHON=../python to create a venv for generating the documentation, e.g., make html PYTHON=venv/bin/python3.
  • Issue #21514: The documentation of the json module now refers to new JSON RFC 7159 instead of obsoleted RFC 4627.
  • Issue #21777: The binary sequence methods on bytes and bytearray are now documented explicitly, rather than assuming users will be able to derive the expected behaviour from the behaviour of the corresponding str methods.
  • Issue #6916: undocument deprecated asynchat.fifo class.
  • Issue #17386: Expanded functionality of the Doc/make.bat script to make it much more comparable to Doc/Makefile.
  • Issue #21312: Update the thread_foobar.h template file to include newer threading APIs. Patch by Jack McCracken.
  • Issue #21043: Remove the recommendation for specific CA organizations and to mention the ability to load the OS certificates.
  • Issue #20765: Add missing documentation for PurePath.with_name() and PurePath.with_suffix().
  • Issue #19407: New package installation and distribution guides based on the Python Packaging Authority tools. Existing guides have been retained as legacy links from the distutils docs, as they still contain some required reference material for tool developers that isn’t recorded anywhere else.
  • Issue #19697: Document cases where __main__.__spec__ is None.
  • Tests:
  • Issue #18982: Add tests for CLI of the calendar module.
  • Issue #19548: Added some additional checks to test_codecs to ensure that statements in the updated documentation remain accurate. Patch by Martin Panter.
  • Issue #22838: All test_re tests now work with unittest test discovery.
  • Issue #22173: Update lib2to3 tests to use unittest test discovery.
  • Issue #16000: Convert test_curses to use unittest.
  • Issue #21456: Skip two tests in test_urllib2net.py if _ssl module not present. Patch by Remi Pointel.
  • Issue #20746: Fix test_pdb to run in refleak mode (-R). Patch by Xavier de Gaye.
  • Issue #22060: test_ctypes has been somewhat cleaned up and simplified; it now uses unittest test discovery to find its tests.
  • Issue #22104: regrtest.py no longer holds a reference to the suite of tests loaded from test modules that don’t define test_main().
  • Issue #22111: Assorted cleanups in test_imaplib. Patch by Milan Oberkirch.
  • Issue #22002: Added load_package_tests function to test.support and used it to implement/augment test discovery in test_asyncio, test_email, test_importlib, test_json, and test_tools.
  • Issue #21976: Fix test_ssl to accept LibreSSL version strings. Thanks to William Orr.
  • Issue #21918: Converted test_tools from a module to a package containing separate test files for each tested script.
  • Issue #9554: Use modern unittest features in test_argparse. Initial patch by Denver Coneybeare and Radu Voicilas.
  • Issue #20155: Changed HTTP method names in failing tests in test_httpservers so that packet filtering software (specifically Windows Base Filtering Engine) does not interfere with the transaction semantics expected by the tests.
  • Issue #19493: Refactored the ctypes test package to skip tests explicitly rather than silently.
  • Issue #18492: All resources are now allowed when tests are not run by regrtest.py.
  • Issue #21634: Fix pystone micro-benchmark: use floor division instead of true division to benchmark integers instead of floating point numbers. Set pystone version to 1.2. Patch written by Lennart Regebro.
  • Issue #21605: Added tests for Tkinter images.
  • Issue #21493: Added test for ntpath.expanduser(). Original patch by Claudiu Popa.
  • Issue #19925: Added tests for the spwd module. Original patch by Vajrasky Kok.
  • Issue #21522: Added Tkinter tests for Listbox.itemconfigure(), PanedWindow.paneconfigure(), and Menu.entryconfigure().
  • Issue #17756: Fix test_code test when run from the installed location.
  • Issue #17752: Fix distutils tests when run from the installed location.
  • Issue #18604: Consolidated checks for GUI availability. All platforms now at least check whether Tk can be instantiated when the GUI resource is requested.
  • Issue #21275: Fix a socket test on KFreeBSD.
  • Issue #21223: Pass test_site/test_startup_imports when some of the extensions are built as builtins.
  • Issue #20635: Added tests for Tk geometry managers.
  • Add test case for freeze.
  • Issue #20743: Fix a reference leak in test_tcl.
  • Issue #21097: Move test_namespace_pkgs into test_importlib.
  • Issue #21503: Use test_both() consistently in test_importlib.
  • Issue #20939: Avoid various network test failures due to new redirect of http://www.python.org/ to https://www.python.org: use http://www.example.com instead.
  • Issue #20668: asyncio tests no longer rely on tests.txt file. (Patch by Vajrasky Kok)
  • Issue #21093: Prevent failures of ctypes test_macholib on OS X if a copy of libz exists in $HOME/lib or /usr/local/lib.
  • Issue #22770: Prevent some Tk segfaults on OS X when running gui tests.
  • Issue #23211: Workaround test_logging failure

New in version 3.4.2 (October 9th, 2014)

  • Core and Builtins -Library:
  • Issue #10510: distutils register and upload methods now use HTML standards compliant CRLF line endings.
  • Issue #9850: Fixed macpath.join() for empty first component. Patch by Oleg Oshmyan.
  • Issue #22427: TemporaryDirectory no longer attempts to clean up twice when used in the with statement in generator.
  • Issue #20912: Now directories added to ZIP file have correct Unix and MS-DOS directory attributes.
  • Issue #21866: ZipFile.close() no longer writes ZIP64 central directory records if allowZip64 is false.
  • Issue #22415: Fixed debugging output of the GROUPREF_EXISTS opcode in the re module. Removed trailing spaces in debugging output.
  • Issue #22423: Unhandled exception in thread no longer causes unhandled AttributeError when sys.stderr is None.
  • Issue #21332: Ensure that bufsize=1 in subprocess.Popen() selects line buffering, rather than block buffering. Patch by Akira Li.

New in version 3.4.1 (May 19th, 2014)

  • Core and Builtins:
  • Issue #21418: Fix a crash in the builtin function super() when called without argument and without current frame (ex: embedded Python).
  • Issue #21425: Fix flushing of standard streams in the interactive interpreter.
  • Issue #21435: In rare cases, when running finalizers on objects in cyclic trash a bad pointer dereference could occur due to a subtle flaw in internal iteration logic.
  • Library:
  • Issue #10744: Fix PEP 3118 format strings on ctypes objects with a nontrivial shape.
  • Issue #20998: Fixed re.fullmatch() of repeated single character pattern with ignore case. Original patch by Matthew Barnett.
  • Issue #21075: fileinput.FileInput now reads bytes from standard stream if binary mode is specified. Patch by Sam Kimbrel.
  • Issue #21396: Fix TextIOWrapper(..., write_through=True) to not force a flush() on the underlying binary stream. Patch by akira.
  • Issue #21470: Do a better job seeding the random number generator by using enough bytes to span the full state space of the Mersenne Twister.
  • Issue #21398: Fix an unicode error in the pydoc pager when the documentation contains characters not encodable to the stdout encoding.
  • Tests:
  • Issue #17756: Fix test_code test when run from the installed location.
  • Issue #17752: Fix distutils tests when run from the installed location.
  • IDLE:
  • Issue #18104: Add idlelib/idle_test/htest.py with a few sample tests to begin consolidating and improving human-validated tests of Idle. Change other files as needed to work with htest. Running the module as __main__ runs all tests.

New in version 3.4.0 (March 17th, 2014)

  • PEP 428, a "pathlib" module providing object-oriented filesystem paths
  • PEP 435, a standardized "enum" module
  • PEP 436, a build enhancement that will help generate introspection information for builtins
  • PEP 442, improved semantics for object finalization
  • PEP 443, adding single-dispatch generic functions to the standard library
  • PEP 445, a new C API for implementing custom memory allocators
  • PEP 446, changing file descriptors to not be inherited by default in subprocesses
  • PEP 450, a new "statistics" module
  • PEP 451, standardizing module metadata for Python's module import system
  • PEP 453, a bundled installer for the pip package manager
  • PEP 454, a new "tracemalloc" module for tracing Python memory allocations
  • PEP 456, a new hash algorithm for Python strings and binary data
  • PEP 3154, a new and improved protocol for pickled objects
  • PEP 3156, a new "asyncio" module, a new framework for asynchronous I/O

New in version 3.4.0 RC 3 (March 10th, 2014)

  • Changes:
  • PEP 428, a "pathlib" module providing object-oriented filesystem paths
  • PEP 435, a standardized "enum" module
  • PEP 436, a build enhancement that will help generate introspection information for builtins
  • PEP 442, improved semantics for object finalization
  • PEP 443, adding single-dispatch generic functions to the standard library
  • PEP 445, a new C API for implementing custom memory allocators
  • PEP 446, changing file descriptors to not be inherited by default in subprocesses
  • PEP 450, a new "statistics" module
  • PEP 451, standardizing module metadata for Python's module import system
  • PEP 453, a bundled installer for the pip package manager
  • PEP 454, a new "tracemalloc" module for tracing Python memory allocations
  • PEP 456, a new hash algorithm for Python strings and binary data
  • PEP 3154, a new and improved protocol for pickled objects
  • PEP 3156, a new "asyncio" module, a new framework for asynchronous I/O

New in version 3.3.5 (March 10th, 2014)

  • Core and Builtins:
  • Issue #20731: Properly position in source code files even if they are opened in text mode. Patch by Serhiy Storchaka.
  • Issue #19619: str.encode, bytes.decode and bytearray.decode now use an internal API to throw LookupError for known non-text encodings, rather than attempting the encoding or decoding operation and then throwing a TypeError for an unexpected output type. (The latter mechanism remains in place for third party non-text encodings)
  • Library:
  • Issue #20778: Fix modulefinder to work with bytecode-only modules.
  • Issue #20791: copy.copy() now doesn’t make a copy when the input is a bytes object. Initial patch by Peter Otten.
  • Issue #20621: Fixes a zipimport bug introduced in 3.3.4 that could cause spurious crashes or SystemErrors when importing modules or packages from a zip file. The change causing the problem was reverted.
  • Issue #20404: io.TextIOWrapper (and hence the open() builtin) now uses the internal codec marking system added for issue #19619 to throw LookupError for known non-text encodings at stream construction time. The existing output type checks remain in place to deal with unmarked third party codecs.
  • Tests:
  • Issue #20743: Fix a reference leak in test_tcl.
  • Tools/Demos:
  • Issue #20535: PYTHONWARNING no longer affects the run_tests.py script. Patch by Arfrever Frehtes Taifersar Arahesis.

New in version 3.3.5 RC 1 (February 24th, 2014)

  • Core and Builtins:
  • Issue #19619: str.encode, bytes.decode and bytearray.decode now use an internal API to throw LookupError for known non-text encodings, rather than attempting the encoding or decoding operation and then throwing a TypeError for an unexpected output type. (The latter mechanism remains in place for third party non-text encodings)
  • Issue #20588: Make Python-ast.c C89 compliant.
  • Issue #20437: Fixed 21 potential bugs when deleting objects references.
  • Issue #20538: UTF-7 incremental decoder produced inconsistant string when input was truncated in BASE64 section.
  • Library:
  • Issue #20635: Fixed grid_columnconfigure() and grid_rowconfigure() methods of Tkinter widgets to work in wantobjects=True mode.
  • Issue #19612: On Windows, subprocess.Popen.communicate() now ignores OSError(22, ‘Invalid argument’) when writing input data into stdin, whereas the process already exited.
  • Issue #6815: os.path.expandvars() now supports non-ASCII environment variables names and values.
  • Issue #17671: Fixed a crash when use non-initialized io.BufferedRWPair. Based on patch by Stephen Tu.
  • Issue #8478: Untokenizer.compat processes first token from iterator input. Patch based on lines from Georg Brandl, Eric Snow, and Gareth Rees.
  • Issue #20594: Avoid name clash with the libc function posix_close.
  • Issue #19856: shutil.move() failed to move a directory to other directory on Windows if source name ends with os.altsep.
  • Issue #14983: email.generator now always adds a line end after each MIME boundary marker, instead of doing so only when there is an epilogue. This fixes an RFC compliance bug and solves an issue with signed MIME parts.
  • Issue #20540: Fix a performance regression (vs. Python 3.2) when layering a multiprocessing Connection over a TCP socket. For small payloads, Nagle’s algorithm would introduce idle delays before the entire transmission of a message.
  • Issue #16983: the new email header parsing code will now decode encoded words that are (incorrectly) surrounded by quotes, and register a defect.
  • Issue #19772: email.generator no longer mutates the message object when doing a down-transform from 8bit to 7bit CTEs.
  • Issue #18805: the netmask/hostmask parsing in ipaddress now more reliably filters out illegal values and correctly allows any valid prefix length.
  • Issue #17369: get_filename was raising an exception if the filename parameter’s RFC2231 encoding was broken in certain ways. This was a regression relative to python2.
  • Issue #20013: Some imap servers disconnect if the current mailbox is deleted, and imaplib did not handle that case gracefully. Now it handles the ‘bye’ correctly.
  • Issue #19920: TarFile.list() no longer fails when outputs a listing containing non-encodable characters. Based on patch by Vajrasky Kok.
  • Issue #20515: Fix NULL pointer dereference introduced by issue #20368.
  • Issue #19186: Restore namespacing of expat symbols inside the pyexpat module.
  • Issue #20426: When passing the re.DEBUG flag, re.compile() displays the debug output every time it is called, regardless of the compilation cache.
  • Issue #20368: The null character now correctly passed from Tcl to Python. Improved error handling in variables-related commands.
  • Issue #20435: Fix _pyio.StringIO.getvalue() to take into account newline translation settings.
  • Issue #20288: fix handling of invalid numeric charrefs in HTMLParser.
  • Issue #20424: Python implementation of io.StringIO now supports lone surrogates.
  • Issue #19456: ntpath.join() now joins relative paths correctly when a drive is present.
  • Issue #19077: tempfile.TemporaryDirectory cleanup is now most likely successful when called during nulling out of modules during shutdown. Misleading exception no longer raised when resource warning is emitted during shutdown.
  • Issue #20367: Fix behavior of concurrent.futures.as_completed() for duplicate arguments. Patch by Glenn Langford.
  • Issue #8260: The read(), readline() and readlines() methods of codecs.StreamReader returned incomplete data when were called after readline() or read(size). Based on patch by Amaury Forgeot d’Arc.
  • IDLE:
  • Issue #20406: Use Python application icons for Idle window title bars. Patch mostly by Serhiy Storchaka.
  • Update the python.gif icon for the Idle classbrowser and pathbowser from the old green snake to the new new blue and yellow snakes.
  • Issue #17721: Remove non-functional configuration dialog help button until we make it actually gives some help when clicked. Patch by Guilherme Simões.
  • Tests:
  • Issue #20743: Fix a reference leak in test_tcl.
  • Issue #20510: Rewrote test_exit in test_sys to match existing comments, use modern unittest features, and use helpers from test.script_helper instead of using subprocess directly. Patch by Gareth Rees.
  • Issue #20532: Tests which use _testcapi are now marked as CPython only.
  • Issue #19920: Added tests for TarFile.list(). Based on patch by Vajrasky Kok.
  • Issue #19990: Added tests for the imghdr module. Based on patch by Claudiu Popa.
  • Issue #20474: Fix test_socket “unexpected success” failures on OS X 10.7+.
  • Issue #20605: Make test_socket getaddrinfo OS X segfault test more robust.
  • Documentation:
  • Issue #20488: Importlib is no longer an implementation of import, it’s the implementation.
  • Build:
  • Issue #20221: Removed conflicting (or circular) hypot definition when compiled with VS 2010 or above. Initial patch by Tabrez Mohammed.
  • Issue #20609: Restored the ability to build 64-bit Windows binaries on 32-bit Windows, which was broken by the change in issue #19788.
  • Tools/Demos:
  • Issue #20535: PYTHONWARNING no longer affects the run_tests.py script. Patch by Arfrever Frehtes Taifersar Arahesis.

New in version 3.4.0 RC 1 (February 11th, 2014)

  • Core and Builtins:
  • Issue #19255: The builtins module is restored to initial value before cleaning other modules. The sys and builtins modules are cleaned last.
  • Issue #20588: Make Python-ast.c C89 compliant.
  • Issue #20437: Fixed 22 potential bugs when deleting objects references.
  • Issue #20500: Displaying an exception at interpreter shutdown no longer risks triggering an assertion failure in PyObject_Str.
  • Issue #20538: UTF-7 incremental decoder produced inconsistent string when input was truncated in BASE64 section.
  • Issue #20404: io.TextIOWrapper (and hence the open() builtin) now uses the internal codec marking system added for issue #19619 to throw LookupError for known non-text encodings at stream construction time. The existing output type checks remain in place to deal with unmarked third party codecs.
  • Issue #17162: Add PyType_GetSlot.
  • Issue #20162: Fix an alignment issue in the siphash24() hash function which caused a crash on PowerPC 64-bit (ppc64).
  • Library:
  • Issue #20530: The signatures for slot builtins have been updated to reflect the fact that they only accept positional-only arguments.
  • Issue #20517: Functions in the os module that accept two filenames now register both filenames in the exception on failure.
  • Issue #20563: The ipaddress module API is now considered stable.
  • Issue #14983: email.generator now always adds a line end after each MIME boundary marker, instead of doing so only when there is an epilogue. This fixes an RFC compliance bug and solves an issue with signed MIME parts.
  • Issue #20540: Fix a performance regression (vs. Python 3.2) when layering a multiprocessing Connection over a TCP socket. For small payloads, Nagle’s algorithm would introduce idle delays before the entire transmission of a message.
  • Issue #16983: the new email header parsing code will now decode encoded words that are (incorrectly) surrounded by quotes, and register a defect.
  • Issue #19772: email.generator no longer mutates the message object when doing a down-transform from 8bit to 7bit CTEs.
  • Issue #20536: the statistics module now correctly handle Decimal instances with positive exponents
  • Issue #18805: the netmask/hostmask parsing in ipaddress now more reliably filters out illegal values and correctly allows any valid prefix length.
  • Issue #20481: For at least Python 3.4, the statistics module will require that all inputs for a single operation be of a single consistent type, or else a mixed of ints and a single other consistent type. This avoids some interoperability issues that arose with the previous approach of coercing to a suitable common type.
  • Issue #20478: the statistics module now treats collections.Counter inputs like any other iterable.
  • Issue #17369: get_filename was raising an exception if the filename parameter’s RFC2231 encoding was broken in certain ways. This was a regression relative to python2.
  • Issue #20013: Some imap servers disconnect if the current mailbox is deleted, and imaplib did not handle that case gracefully. Now it handles the ‘bye’ correctly.
  • Issue #20531: Revert 3.4 version of fix for #19063, and apply the 3.3 version. That is, do not raise an error if unicode is passed to email.message.Message.set_payload.
  • Issue #20476: If a non-compat32 policy is used with any of the email parsers, EmailMessage is now used as the factory class. The factory class should really come from the policy; that will get fixed in 3.5.
  • Issue #19920: TarFile.list() no longer fails when outputs a listing containing non-encodable characters. Based on patch by Vajrasky Kok.
  • Issue #20515: Fix NULL pointer dereference introduced by issue #20368.
  • Issue #19186: Restore namespacing of expat symbols inside the pyexpat module.
  • Issue #20053: ensurepip (and hence venv) are no longer affected by the settings in the default pip configuration file.
  • Issue #20426: When passing the re.DEBUG flag, re.compile() displays the debug output every time it is called, regardless of the compilation cache.
  • Issue #20368: The null character now correctly passed from Tcl to Python. Improved error handling in variables-related commands.
  • Issue #20435: Fix _pyio.StringIO.getvalue() to take into account newline translation settings.
  • tracemalloc: Fix slicing traces and fix slicing a traceback.
  • Issue #20354: Fix an alignment issue in the tracemalloc module on 64-bit platforms. Bug seen on 64-bit Linux when using “make profile-opt”.
  • Issue #17159: inspect.signature now accepts duck types of functions, which adds support for Cython functions. Initial patch by Stefan Behnel.
  • Issue #18801: Fix inspect.classify_class_attrs to correctly classify object.__new__ and object.__init__.
  • Fixed cmath.isinf’s name in its argument parsing code.
  • Issue #20311, #20452: poll and epoll now round the timeout away from zero, instead of rounding towards zero, in select and selectors modules: select.epoll.poll(), selectors.PollSelector.poll() and selectors.EpollSelector.poll(). For example, a timeout of one microsecond (1e-6) is now rounded to one millisecondi (1e-3), instead of being rounded to zero. However, the granularity property and asyncio’s resolution feature were removed again.
  • asyncio: Some refactoring; various fixes; add write flow control to unix pipes; Future.set_exception() instantiates the exception argument if it is a class; improved proactor pipe transport; support wait_for(f, None); don’t log broken/disconnected pipes; use ValueError instead of assert for forbidden subprocess_{shell,exec} arguments; added a convenience API for subprocess management; added StreamReader.at_eof(); properly handle duplicate coroutines/futures in gather(), wait(), as_completed(); use a bytearray for buffering in StreamReader; and more.
  • Issue #20288: fix handling of invalid numeric charrefs in HTMLParser.
  • Issue #20424: Python implementation of io.StringIO now supports lone surrogates.
  • Issue #20308: inspect.signature now works on classes without user-defined __init__ or __new__ methods.
  • Issue #20372: inspect.getfile (and a bunch of other inspect functions that use it) doesn’t crash with unexpected AttributeError on classes defined in C without __module__.
  • Issue #20356: inspect.signature formatting uses ‘/’ to separate positional-only parameters from others.
  • Issue #20223: inspect.signature now supports methods defined with functools.partialmethods.
  • Issue #19456: ntpath.join() now joins relative paths correctly when a drive is present.
  • Issue #19077: tempfile.TemporaryDirectory cleanup no longer fails when called during shutdown. Emitting resource warning in __del__ no longer fails. Original patch by Antoine Pitrou.
  • Issue #20394: Silence Coverity warning in audioop module.
  • Issue #20367: Fix behavior of concurrent.futures.as_completed() for duplicate arguments. Patch by Glenn Langford.
  • Issue #8260: The read(), readline() and readlines() methods of codecs.StreamReader returned incomplete data when were called after readline() or read(size). Based on patch by Amaury Forgeot d’Arc.
  • Issue #20105: the codec exception chaining now correctly sets the traceback of the original exception as its __traceback__ attribute.
  • Issue #17481: inspect.getfullargspec() now uses inspect.signature() API.
  • Issue #15304: concurrent.futures.wait() can block forever even if Futures have completed. Patch by Glenn Langford.
  • Issue #14455: plistlib: fix serializing integers integers in the range of an unsigned long long but outside of the range of signed long long for binary plist files.
  • IDLE:
  • Issue #20406: Use Python application icons for Idle window title bars. Patch mostly by Serhiy Storchaka.
  • Update the python.gif icon for the Idle classbrowser and pathbowser from the old green snake to the new new blue and yellow snakes.
  • Issue #17721: Remove non-functional configuration dialog help button until we make it actually gives some help when clicked. Patch by Guilherme Simões.
  • Tests:
  • Issue #20532: Tests which use _testcapi now are marked as CPython only.
  • Issue #19920: Added tests for TarFile.list(). Based on patch by Vajrasky Kok.
  • Issue #19990: Added tests for the imghdr module. Based on patch by Claudiu Popa.
  • Issue #20474: Fix test_socket “unexpected success” failures on OS X 10.7+.
  • Tools/Demos:
  • Issue #20530: Argument Clinic’s signature format has been revised again. The new syntax is highly human readable while still preventing false positives. The syntax also extends Python syntax to denote “self” and positional-only parameters, allowing inspect.Signature objects to be totally accurate for all supported builtins in Python 3.4.
  • Issue #20456: Argument Clinic now observes the C preprocessor conditional compilation statements of the C files it parses. When a Clinic block is inside a conditional code, it adjusts its output to match, including automatically generating an empty methoddef macro.
  • Issue #20456: Cloned functions in Argument Clinic now use the correct name, not the name of the function they were cloned from, for text strings inside generated code.
  • Issue #20456: Fixed Argument Clinic’s test suite and “–converters” feature.
  • Issue #20456: Argument Clinic now allows specifying different names for a parameter in Python and C, using “as” on the parameter line.
  • Issue #20326: Argument Clinic now uses a simple, unique signature to annotate text signatures in docstrings, resulting in fewer false positives. “self” parameters are also explicitly marked, allowing inspect.Signature() to authoritatively detect (and skip) said parameters.
  • Issue #20326: Argument Clinic now generates separate checksums for the input and output sections of the block, allowing external tools to verify that the input has not changed (and thus the output is not out-of-date).
  • Build:
  • Issue #20465: Update SQLite shipped with OS X installer to 3.8.3.
  • C-API:
  • Issue #20517: Added new functions allowing OSError exceptions to reference two filenames instead of one: PyErr_SetFromErrnoWithFilenameObjects() and PyErr_SetExcFromWindowsErrWithFilenameObjects().
  • Documentation:
  • Issue #20488: Change wording to say importlib is the implementation of import instead of just an implementation.
  • Issue #6386: Clarify in the tutorial that specifying a symlink to execute means the directory containing the executed script and not the symlink is added to sys.path.

New in version 3.3.4 (February 11th, 2014)

  • Library:
  • Issue #20374: Fix build warnings of the readline module with libedit on Mac.

New in version 3.3.4 RC 1 (January 27th, 2014)

  • Core and Builtins:
  • Issue #17825: Cursor “^” is correctly positioned for SyntaxError and IndentationError.
  • Issue #2382: SyntaxError cursor “^” is now written at correct position in most cases when multibyte characters are in line (before “^”). This still not works correctly with wide East Asian characters.
  • Issue #18960: The first line of Python script could be executed twice when the source encoding was specified on the second line. Now the source encoding declaration on the second line isn’t effective if the first line contains anything except a comment. ‘python -x’ works now again with files with the source encoding declarations, and can be used to make Python batch files on Windows.
  • Issue #17432: Drop UCS2 from names of Unicode functions in python3.def.
  • Issue #19969: PyBytes_FromFormatV() now raises an OverflowError if “%c” argument is not in range [0; 255].
  • Issue #14432: Generator now clears the borrowed reference to the thread state. Fix a crash when a generator is created in a C thread that is destroyed while the generator is still used. The issue was that a generator contains a frame, and the frame kept a reference to the Python state of the destroyed C thread. The crash occurs when a trace function is setup.
  • Issue #19932: Fix typo in import.h, missing whitespaces in function prototypes.
  • Issue #19729: In str.format(), fix recursive expansion in format spec.
  • Issue #19638: Fix possible crash / undefined behaviour from huge (more than 2 billion characters) input strings in _Py_dg_strtod.
  • Library:
  • Issue #16042: CVE-2013-1752: smtplib: Limit amount of data read by limiting the call to readline(). Original patch by Christian Heimes.
  • Issue #20317: ExitStack.__exit__ could create a self-referential loop if an exception raised by a cleanup operation already had its context set correctly (for example, by the @contextmanager decorator). The infinite loop this caused is now avoided by checking if the expected context is already set before trying to fix it.
  • Issue #20374: Fix build with GNU readline >= 6.3.
  • Issue #20262: Warnings are raised now when duplicate names are added in the ZIP file or too long ZIP file comment is truncated.
  • Issue #18574: Added missing newline in 100-Continue reply from http.server.BaseHTTPRequestHandler. Patch by Nikolaus Rath.
  • Issue #20270: urllib.urlparse now supports empty ports.
  • Issue #20243: TarFile no longer raise ReadError when opened in write mode.
  • Issue #20238: TarFile opened with external fileobj and “w:gz” mode didn’t write complete output on close.
  • Issue #20245: The open functions in the tarfile module now correctly handle empty mode.
  • Issue #20242: Fixed basicConfig() format strings for the alternative formatting styles. Thanks to kespindler for the bug report and patch.
  • Issue #20246: Fix buffer overflow in socket.recvfrom_into.
  • Issues #20206 and #5803: Fix edge case in email.quoprimime.encode where it truncated lines ending in a character needing encoding but no newline by using a more efficient algorithm that doesn’t have the bug.
  • Issue #19082: Working xmlrpc.server and xmlrpc.client examples. Both in modules and in documentation. Initial patch contributed by Vajrasky Kok.
  • Issue #20138: The wsgiref.application_uri() and wsgiref.request_uri() functions now conform to PEP 3333 when handle non-ASCII URLs.
  • Issue #19097: Raise the correct Exception when cgi.FieldStorage is given an invalid fileobj.
  • Issue #20217: Fix build in SCHED_SPORADIC is defined.
  • Issue #13107: argparse and optparse no longer raises an exception when output a help on environment with too small COLUMNS. Based on patch by Elazar Gershuni.
  • Issue #20207: Always disable SSLv2 except when PROTOCOL_SSLv2 is explicitly asked for.
  • Issue #18960: The tokenize module now ignore the source encoding declaration on the second line if the first line contains anything except a comment.
  • Issue #20078: Reading malformed zipfiles no longer hangs with 100% CPU consumption.
  • Issue #20113: os.readv() and os.writev() now raise an OSError exception on error instead of returning -1.
  • Issue #20072: Fixed multiple errors in tkinter with wantobjects is False.
  • Issue #20108: Avoid parameter name clash in inspect.getcallargs().
  • Issue #12692: Backport the fix for ResourceWarning in test_urllib2net. This also helps in closing the socket when Connection Close header is not sent.
  • Issue #19422: Explicitly disallow non-SOCK_STREAM sockets in the ssl module, rather than silently let them emit clear text data.
  • Issue #18116: getpass was always getting an error when testing /dev/tty, and thus was always falling back to stdin, and would then raise an exception if stdin could not be used (such as /dev/null). It also leaked an open file. All of these issues are now fixed.
  • Issue #20027: Fixed locale aliases for devanagari locales.
  • Issue #20067: Tkinter variables now work when wantobjects is false.
  • Issue #19020: Tkinter now uses splitlist() instead of split() in configure methods.
  • Fix TypeError on “setup.py upload –show-response”.
  • Issue #12226: HTTPS is now used by default when connecting to PyPI.
  • Issue #20045: Fix “setup.py register –list-classifiers”.
  • Issue #18879: When a method is looked up on a temporary file, avoid closing the file before the method is possibly called.
  • Issue #20034: Updated alias mapping to most recent locale.alias file from X.org distribution using makelocalealias.py.
  • Issue #5815: Fixed support for locales with modifiers. Fixed support for locale encodings with hyphens.
  • Issue #20026: Fix the sqlite module to handle correctly invalid isolation level (wrong type).
  • Issue #18829: csv.Dialect() now checks type for delimiter, escapechar and quotechar fields. Original patch by Vajrasky Kok.
  • Issue #19855: uuid.getnode() on Unix now looks on the PATH for the executables used to find the mac address, with /sbin and /usr/sbin as fallbacks.
  • Issue #20007: HTTPResponse.read(0) no more prematurely closes connection. Original patch by Simon Sapin.
  • Issue #19912: Fixed numerous bugs in ntpath.splitunc().
  • Issue #19911: ntpath.splitdrive() now correctly processes the ‘İ’ character (U+0130, LATIN CAPITAL LETTER I WITH DOT ABOVE).
  • Issue #19532: python -m compileall with no filename/directory arguments now respects the -f and -q flags instead of ignoring them.
  • Issue #19623: Fixed writing to unseekable files in the aifc module.
  • Issue #17919: select.poll.register() again works with poll.POLLNVAL on AIX. Fixed integer overflow in the eventmask parameter.
  • Issue #19063: if a Charset’s body_encoding was set to None, the email package would generate a message claiming the Content-Transfer-Encoding was 7bit, and produce garbage output for the content. This now works. A couple of other set_payload mishandlings of non-ASCII are also fixed.
  • Issue #17200: telnetlib’s read_until and expect timeout was broken by the fix to Issue #14635 in Python 3.3.0 to be interpreted as milliseconds instead of seconds when the platform supports select.poll (ie: everywhere). It is now treated as seconds once again.
  • Issue #17429: platform.linux_distribution() now decodes files from the UTF-8 encoding with the surrogateescape error handler, instead of decoding from the locale encoding in strict mode. It fixes the function on Fedora 19 which is probably the first major distribution release with a non-ASCII name. Patch written by Toshio Kuratomi.
  • Issue #19929: Call os.read with 32768 within subprocess.Popen.communicate rather than 4096 for efficiency. A microbenchmark shows Linux and OS X both using ~50% less cpu time this way.
  • Issue #19506: Use a memoryview to avoid a data copy when piping data to stdin within subprocess.Popen.communicate. 5-10% less cpu usage.
  • Issue #19839: Fix regression in bz2 module’s handling of non-bzip2 data at EOF, and analogous bug in lzma module.
  • Issue #19138: doctest’s IGNORE_EXCEPTION_DETAIL now allows a match when no exception detail exists (no colon following the exception’s name, or a colon does follow but no text follows the colon).
  • Issue #19834: Support unpickling of exceptions pickled by Python 2.
  • Issue #15798: Fixed subprocess.Popen() to no longer fail if file descriptor 0, 1 or 2 is closed.
  • Issue #19088: Fixed incorrect caching of the copyreg module in object.__reduce__() and object.__reduce_ex__().
  • Fixed _pickle.Unpickler to not fail when loading empty strings as persistent IDs.
  • Issue #11480: Fixed copy.copy to work with classes with custom metaclasses. Patch by Daniel Urban.
  • Issue #6477: Added support for pickling the types of built-in singletons (i.e., Ellipsis, NotImplemented, None).
  • Issue #11508: Fixed uuid.getnode() and uuid.uuid1() on environment with virtual interface. Original patch by Kent Frazier.
  • Issue #11489: JSON decoder now accepts lone surrogates.
  • Issue #19545: Avoid chained exceptions while passing stray % to time.strptime(). Initial patch by Claudiu Popa.
  • Issue #19633: Fixed writing not compressed 16- and 32-bit wave files on big-endian platforms.
  • Issue #19449: in csv’s writerow, handle non-string keys when generating the error message that certain keys are not in the ‘fieldnames’ list.
  • Fix test.support.bind_port() to not cause an error when Python was compiled on a system with SO_REUSEPORT defined in the headers but run on a system with an OS kernel that does not support that reasonably new socket option.
  • Fix compilation error under gcc of the ctypes module bundled libffi for arm.
  • Issue #19523: Closed FileHandler leak which occurred when delay was set.
  • Issue #13674: Prevented time.strftime from crashing on Windows when given a year before 1900 and a format of %y.
  • Issue #19544 and Issue #6286: Restore use of urllib over http allowing use of http_proxy for Distutils upload command, a feature accidentally lost in the rollback of distutils2.
  • Issue #19544 and Issue #7457: Restore the read_pkg_file method to distutils.dist.DistributionMetadata accidentally removed in the undo of distutils2.
  • Issue #1575020: Fixed support of 24-bit wave files on big-endian platforms.
  • Issue #19480: HTMLParser now accepts all valid start-tag names as defined by the HTML5 standard.
  • Issue #6157: Fixed tkinter.Text.debug(). Original patch by Guilherme Polo.
  • Issue #6160: The bbox() method of tkinter.Spinbox now returns a tuple of integers instead of a string. Based on patch by Guilherme Polo.
  • Issue #10197: Rework subprocess.get[status]output to use subprocess functionality and thus to work on Windows. Patch by Nick Coghlan.
  • Issue #19286: Directories in package_data are no longer added to the filelist, preventing failure outlined in the ticket.
  • IDLE:
  • Issue #17390: Add Python version to Idle editor window title bar. Original patches by Edmond Burnett and Kent Johnson.
  • Issue #18960: IDLE now ignores the source encoding declaration on the second line if the first line contains anything except a comment.
  • Issue #20058: sys.stdin.readline() in IDLE now always returns only one line.
  • Issue #19481: print() of string subclass instance in IDLE no longer hangs.
  • Issue #18270: Prevent possible IDLE AttributeError on OS X when no initial shell window is present.
  • Tests:
  • Issue #19804: The test_find_mac test in test_uuid is now skipped if the ifconfig executable is not available.
  • Issue #19886: Use better estimated memory requirements for bigmem tests.
  • Issue #20055: Fix test_shutil under Windows with symlink privileges held. Patch by Vajrasky Kok.
  • Issue #19938: Re-enabled test_bug_1333982 in test_dis, which had been disabled since 3.0 due to the changes in listcomp handling.
  • Issue #19320: test_tcl no longer fails when wantobjects is false.
  • Issue #19683: Removed empty tests from test_minidom. Patch by Ajitesh Gupta.
  • Issue #19919: Fix flaky SSL test. connect_ex() sometimes returns EWOULDBLOCK on Windows or VMs hosted on Windows.
  • Issue #19912: Added tests for ntpath.splitunc().
  • Issue #19828: Fixed test_site when the whole suite is run with -S.
  • Issue #19928: Implemented a test for repr() of cell objects.
  • Issue #19535: Fixed test_docxmlrpc when python is run with -OO.
  • Issue #19926: Removed unneeded test_main from test_abstract_numbers. Patch by Vajrasky Kok.
  • Issue #19595, #19987: Re-enabled a long-disabled test in test_winsound.
  • Issue #19588: Fixed tests in test_random that were silently skipped most of the time. Patch by Julian Gindi.
  • Issue #19596: Set untestable tests in test_importlib to None to avoid reporting success on empty tests.
  • Issue #19440: Clean up test_capi by removing an unnecessary __future__ import, converting from test_main to unittest.main, and running the _testcapi module tests within a unittest TestCase.
  • Issue #18702, 19572: All skipped tests now reported as skipped.
  • Issue #19085: Added basic tests for all tkinter widget options.
  • Documentation:
  • Issue #20265: Updated some parts of the Using Windows document.
  • Issue #20266: Updated some parts of the Windows FAQ.
  • Issue #20255: Updated the about and bugs pages.
  • Issue #20253: Fixed a typo in the ipaddress docs that advertised an illegal attribute name. Found by INADA Naoki.
  • Issue #19963: Document that importlib.import_module() no longer requires importing parent packages separately.
  • Issue #18840: Introduce the json module in the tutorial, and de-emphasize the pickle module.
  • Issue #19845: Updated the Compiling Python on Windows section.
  • Issue #19795: Improved markup of True/False constants.
  • Issue #18326: Clarify that list.sort’s arguments are keyword-only. Also, attempt to reduce confusion in the glossary by not saying there are different “types” of arguments and parameters.
  • Build:
  • Issue #19788: kill_python(_d).exe is now run as a PreBuildEvent on the pythoncore sub-project. This should prevent build errors due a previous build’s python(_d).exe still running.
  • Add workaround for VS 2010 nmake clean issue. VS 2010 doesn’t set up PATH for nmake.exe correctly.
  • Tools/Demos:
  • Issue #19936: Added executable bits or shebang lines to Python scripts which requires them. Disable executable bits and shebang lines in test and benchmark files in order to prevent using a random system python, and in source files of modules which don’t provide command line interface. Fixed shebang line to use python3 executable in the unittestgui script.
  • Issue #18960: 2to3 and the findnocoding.py script now ignore the source encoding declaration on the second line if the first line contains anything except a comment.

New in version 3.4.0 Beta (January 27th, 2014)

  • Major new features and changes:
  • PEP 428, a "pathlib" module providing object-oriented filesystem paths
  • PEP 435, a standardized "enum" module
  • PEP 436, a build enhancement that will help generate introspection information for builtins
  • PEP 442, improved semantics for object finalization
  • PEP 443, adding single-dispatch generic functions to the standard library
  • PEP 445, a new C API for implementing custom memory allocators
  • PEP 446, changing file descriptors to not be inherited by default in subprocesses
  • PEP 450, a new "statistics" module
  • PEP 451, standardizing module metadata for Python's module import system
  • PEP 453, a bundled installer for the pip package manager
  • PEP 454, a new "tracemalloc" module for tracing Python memory allocations
  • PEP 456, a new hash algorithm for Python strings and binary data
  • PEP 3154, a new and improved protocol for pickled objects
  • PEP 3156, a new "asyncio" module, a new framework for asynchronous I/O

New in version 3.3.3 RC 2 (November 12th, 2013)

  • PEP 380, syntax for delegating to a subgenerator (yield from)
  • PEP 393, flexible string representation (doing away with the distinction between "wide" and "narrow" Unicode builds)
  • A C implementation of the "decimal" module, with up to 120x speedup for decimal-heavy applications
  • The import system (__import__) is based on importlib by default
  • The new "lzma" module with LZMA/XZ support
  • PEP 397, a Python launcher for Windows
  • PEP 405, virtual environment support in core
  • PEP 420, namespace package support
  • PEP 3151, reworking the OS and IO exception hierarchy
  • PEP 3155, qualified name for classes and functions
  • PEP 409, suppressing exception context
  • PEP 414, explicit Unicode literals to help with porting
  • PEP 418, extended platform-independent clocks in the "time" module
  • PEP 412, a new key-sharing dictionary implementation that significantly saves memory for object-oriented code
  • PEP 362, the function-signature object
  • The new "faulthandler" module that helps diagnosing crashes
  • The new "unittest.mock" module
  • The new "ipaddress" module
  • The "sys.implementation" attribute
  • A policy framework for the email package, with a provisional (see PEP 411) policy that adds much improved unicode support for email header parsing
  • A "collections.ChainMap" class for linking mappings to a single unit
  • Wrappers for many more POSIX functions in the "os" and "signal" modules, as well as other useful functions such as "sendfile()"
  • Hash randomization, introduced in earlier bugfix releases, is now switched on by default

New in version 3.4.0 Alpha 4 (October 22nd, 2013)

  • Core and Builtins:
  • Issue #19301: Give classes and functions that are explicitly marked global a global qualname.
  • Issue #19279: UTF-7 decoder no longer produces illegal strings.
  • Issue #16612: Add “Argument Clinic”, a compile-time preprocessor for C files to generate argument parsing code. (See PEP 436.)
  • Issue #18810: Shift stat calls in importlib.machinery.FileFinder such that the code is optimistic that if something exists in a directory named exactly like the possible package being searched for that it’s in actuality a directory.
  • Issue #18416: importlib.machinery.PathFinder now treats ‘’ as the cwd and importlib.machinery.FileFinder no longer special-cases ‘’ to ‘.’. This leads to modules imported from cwd to now possess an absolute file path for __file__ (this does not affect modules specified by path on the CLI but it does affect -m/runpy). It also allows FileFinder to be more consistent by not having an edge case.
  • Issue #4555: All exported C symbols are now prefixed with either “Py” or “_Py”.
  • Issue #19219: Speed up marshal.loads(), and make pyc files slightly (5% to 10%) smaller.
  • Issue #19221: Upgrade Unicode database to version 6.3.0.
  • Issue #16742: The result of the C callback PyOS_ReadlineFunctionPointer must now be a string allocated by PyMem_RawMalloc() or PyMem_RawRealloc() (or NULL if an error occurred), instead of a string allocated by PyMem_Malloc() or PyMem_Realloc().
  • Issue #19199: Remove PyThreadState.tick_counter field
  • Fix macro expansion of _PyErr_OCCURRED(), and make sure to use it in at least one place so as to avoid regressions.
  • Issue #19087: Improve bytearray allocation in order to allow cheap popping of data at the front (slice deletion).
  • Issue #19014: memoryview.cast() is now allowed on zero-length views.
  • Issue #18690: memoryview is now automatically registered with collections.abc.Sequence
  • Issue #19078: memoryview now correctly supports the reversed builtin (Patch by Claudiu Popa)
  • Library:
  • Issue #8964: fix platform._sys_version to handle IronPython 2.6+. Patch by Martin Matusiak.
  • Issue #18958: Improve error message for json.load(s) while passing a string that starts with a UTF-8 BOM.
  • Issue #19307: Improve error message for json.load(s) while passing objects of the wrong type.
  • Issue #16038: CVE-2013-1752: ftplib: Limit amount of data read by limiting the call to readline(). Original patch by Michał Jastrzębski and Giampaolo Rodola.
  • Issue #17087: Improved the repr for regular expression match objects.
  • Issue #18235: Fix the sysconfig variables LDSHARED and BLDSHARED under AIX. Patch by David Edelsohn.
  • Issue #18606: Add the new “statistics” module (PEP 450). Contributed by Steven D’Aprano.
  • Issue #12866: The audioop module now supports 24-bit samples.
  • Issue #19254: Provide an optimized Python implementation of pbkdf2_hmac.
  • Issues #19201, #19222, #19223: Add “x” mode (exclusive creation) in opening file to bz2, gzip and lzma modules. Patches by Tim Heaney and Vajrasky Kok.
  • Fix a reference count leak in _sre.
  • Issue #19262: Initial check in of the ‘asyncio’ package (a.k.a. Tulip, a.k.a. PEP 3156). There are no docs yet, and the PEP is slightly out of date with the code. This module will have provisional status in Python 3.4.
  • Issue #19276: Fixed the wave module on 64-bit big-endian platforms.
  • Issue #19266: Rename the new-in-3.4 contextlib.ignore context manager to contextlib.suppress in order to be more consistent with existing descriptions of that operation elsewhere in the language and standard library documentation (Patch by Zero Piraeus).
  • Issue #18891: Completed the new email package (provisional) API additions by adding new classes EmailMessage, MIMEPart, and ContentManager.
  • Issue #18281: Unused stat constants removed from tarfile.
  • Issue #18468: The re.split, re.findall, and re.sub functions and the group() and groups() methods of match object now always return a string or a bytes object.
  • Issue #18725: The textwrap module now supports truncating multiline text.
  • Issue #18776: atexit callbacks now display their full traceback when they raise an exception.
  • Issue #17827: Add the missing documentation for codecs.encode and codecs.decode.
  • Issue #19218: Rename collections.abc to _collections_abc in order to speed up interpreter start.
  • Issue #18582: Add ‘pbkdf2_hmac’ to the hashlib module. It implements PKCS#5 password-based key derivation functions with HMAC as pseudorandom function.
  • Issue #19131: The aifc module now correctly reads and writes sampwidth of compressed streams.
  • Issue #19209: Remove import of copyreg from the os module to speed up interpreter startup. stat_result and statvfs_result are now hard-coded to reside in the os module.
  • Issue #19205: Don’t import the ‘re’ module in site and sysconfig module to to speed up interpreter start.
  • Issue #9548: Add a minimal “_bootlocale” module that is imported by the _io module instead of the full locale module.
  • Issue #18764: remove the ‘print’ alias for the PDB ‘p’ command so that it no longer shadows the print function.
  • Issue #19158: a rare race in BoundedSemaphore could allow .release() too often.
  • Issue #15805: Add contextlib.redirect_stdout().
  • Issue #18716: Deprecate the formatter module.
  • Issue #18037: 2to3 now escapes ‘u’ and ‘U’ in native strings.
  • Issue #17839: base64.decodebytes and base64.encodebytes now accept any object that exports a 1 dimensional array of bytes (this means the same is now also true for base64_codec)
  • Issue #19132: The pprint module now supports compact mode.
  • Issue #19137: The pprint module now correctly formats instances of set and frozenset subclasses.
  • Issue #10042: functools.total_ordering now correctly handles NotImplemented being returned by the underlying comparison function (Patch by Katie Miller)
  • Issue #19092: contextlib.ExitStack now correctly reraises exceptions from the __exit__ callbacks of inner context managers (Patch by Hrvoje Nikšić)
  • Issue #12641: Avoid passing “-mno-cygwin” to the mingw32 compiler, except when necessary. Patch by Oscar Benjamin.
  • Issue #5845: In site.py, only load readline history from ~/.python_history if no history has been read already. This avoids double writes to the history file at shutdown.
  • Properly initialize all fields of a SSL object after allocation.
  • Issue #19095: SSLSocket.getpeercert() now raises ValueError when the SSL handshake hasn’t been done.
  • Issue #4366: Fix building extensions on all platforms when –enable-shared is used.
  • Issue #19030: Fixed inspect.getmembers and inspect.classify_class_attrs to attempt activating descriptors before falling back to a __dict__ search for faulty descriptors. inspect.classify_class_attrs no longer returns Attributes whose home class is None.
  • C API:
  • Issue #1772673: The type of char* arguments now changed to const char*.
  • Issue #16129: Added a Py_SetStandardStreamEncoding pre-initialization API to allow embedding applications like Blender to force a particular encoding and error handler for the standard IO streams (initial patch by Bastien Montagne)
  • Tests:
  • Issue #19275: Fix test_site on AMD64 Snow Leopard
  • Issue #14407: Fix unittest test discovery in test_concurrent_futures.
  • Issue #18919: Unified and extended tests for audio modules: aifc, sunau and wave.
  • Issue #18714: Added tests for pdb.find_function().
  • Documentation:
  • Issue #18758: Fixed and improved cross-references.
  • Issue #18972: Modernize email examples and use the argparse module in them.
  • Build:
  • Issue #19130: Correct PCbuild/readme.txt, Python 3.3 and 3.4 require VS 2010.
  • Issue #15663: Update OS X 10.6+ installer to use Tcl/Tk 8.5.15.
  • Issue #14499: Fix several problems with OS X universal build support
  • Issue #19019: Change the OS X installer build script to use CFLAGS instead of OPT for special build options. By setting OPT, some compiler-specific options like -fwrapv were overridden and thus not used, which could result in broken interpreters when building with clang.

New in version 3.4.0 Alpha 2 (September 9th, 2013)

  • PEP 446, changing file descriptors to not be inherited by default in subprocesses

New in version 3.4.0 Alpha 1 (August 5th, 2013)

  • Python 3.4 includes a range of improvements of the 3.x series, including hundreds of small improvements and bug fixes.
  • Major new features and changes in the 3.4 release series so far include:
  • PEP 435, a standardized "enum" module
  • PEP 442, improved semantics for object finalization
  • PEP 443, adding single-dispatch generic functions to the standard library
  • PEP 445, a new C API for implementing custom memory allocators

New in version 3.3.2 (May 16th, 2013)

  • Core and Builtins:
  • Issue #17237: Fix crash in the ASCII decoder on m68k.
  • Issue #17408: Avoid using an obsolete instance of the copyreg module when the interpreter is shutdown and then started again.
  • Issue #17863: In the interactive console, don’t loop forever if the encoding can’t be fetched from stdin.
  • Issue #17867: Raise an ImportError if __import__ is not found in __builtins__.
  • Issue #17857: Prevent build failures with pre-3.5.0 versions of sqlite3, such as was shipped with Centos 5 and Mac OS X 10.4.
  • Issue #17413: sys.settrace callbacks were being passed a string instead of an exception instance for the ‘value’ element of the arg tuple if the exception originated from C code; now an exception instance is always provided.
  • Issue #17782: Fix undefined behaviour on platforms where struct timespec‘s “tv_nsec” member is not a C long.
  • Issue #17715: Fix segmentation fault from raising an exception in a __trunc__ method.
  • Issue #16447: Fixed potential segmentation fault when setting __name__ on a class.
  • Issue #17669: Fix crash involving finalization of generators using yield from.
  • Issue #17619: Make input() check for Ctrl-C correctly on Windows.
  • Issue #17610: Don’t rely on non-standard behavior of the C qsort() function.
  • Issue #17357: Add missing verbosity output when using -v/-vv.
  • Library:
  • Issue #17606: Fixed support of encoded byte strings in the XMLGenerator
  • .characters() and ignorableWhitespace() methods. Original patch by Sebastian Ortiz Vasquez.
  • Issue #17732: Ignore distutils.cfg options pertaining to install paths if a virtual environment is active.
  • Issue #1159051: Back out a fix for handling corrupted gzip files that broke backwards compatibility.
  • Issue #17915: Fix interoperability of xml.sax with file objects returned by codecs.open().
  • Issue #16601: Restarting iteration over tarfile no more continues from where it left off. Patch by Michael Birtwell.
  • Issue #17289: The readline module now plays nicer with external modules or applications changing the rl_completer_word_break_characters global variable. Initial patch by Bradley Froehle.
  • Issue #12181: select module: Fix struct kevent definition on OpenBSD 64-bit platforms. Patch by Federico Schwindt.
  • Issue #14173: Avoid crashing when reading a signal handler during interpreter shutdown.
  • Issue #16316: mimetypes now recognizes the .xz and .txz (.tar.xz) extensions.
  • Issue #15902: Fix imp.load_module() accepting None as a file when loading an extension module.
  • Issue #17802: Fix an UnboundLocalError in html.parser. Initial tests by Thomas Barlow.
  • Issue #15535: Fix namedtuple pickles which were picking up the OrderedDict instead of just the underlying tuple.
  • Issue #17192: Restore the patch for Issue #11729 which was ommitted in 3.3.1 when updating the bundled version of libffi used by ctypes. Update many libffi files that were missed in 3.3.1’s update to libffi-3.0.13.
  • Issue #17358: Modules loaded by imp.load_source() and load_compiled() (and by extention load_module()) now have a better chance of working when reloaded.
  • Issue #17353: Plistlib emitted empty data tags with deeply nested datastructures
  • Issue #11714: Use ‘with’ statements to assure a Semaphore releases a condition variable. Original patch by Thomas Rachel.
  • Issue #17795: Reverted backwards-incompatible change in SysLogHandler with Unix domain sockets.
  • Issue #17555: Fix ForkAwareThreadLock so that size of after fork registry does not grow exponentially with generation of process.
  • Issue #17707: multiprocessing.Queue’s get() method does not block for short timeouts.
  • Isuse #17720: Fix the Python implementation of pickle.Unpickler to correctly process the APPENDS opcode when it is used on non-list objects.
  • Issue #17012: shutil.which() no longer fallbacks to the PATH environment variable if empty path argument is specified. Patch by Serhiy Storchaka.
  • Issue #17710: Fix pickle raising a SystemError on bogus input.
  • Issue #17341: Include the invalid name in the error messages from re about invalid group names.
  • Issue #17702: os.environ now raises KeyError with the original environment variable name (str on UNIX), instead of using the encoded name (bytes on UNIX).
  • Issue #16163: Make the importlib based version of pkgutil.iter_importers work for submodules. Initial patch by Berker Peksag.
  • Issue #16804: Fix a bug in the ‘site’ module that caused running ‘python -S -m site’ to incorrectly throw an exception.
  • Issue #17016: Get rid of possible pointer wraparounds and integer overflows in the re module. Patch by Nickolai Zeldovich.
  • Issue #16658: add missing return to HTTPConnection.send() Patch by Jeff Knupp.
  • Issue #14971: unittest test discovery no longer gets confused when a function has a different __name__ than its name in the TestCase class dictionary.
  • Issue #17678: Fix DeprecationWarning in the http/cookiejar.py by changing the usage of get_origin_req_host() to origin_req_host.
  • Issue #17666: Fix reading gzip files with an extra field.
  • Issue #17502: Process DEFAULT values in mock side_effect that returns iterator. Patch by Michael Foord.
  • Issue #17572: Avoid chained exceptions while passing bad directives to time.strptime(). Initial patch by Claudiu Popa.
  • Issue #17435: threading.Timer’s __init__ method no longer uses mutable default values for the args and kwargs parameters.
  • Issue #17526: fix an IndexError raised while passing code without filename to inspect.findsource(). Initial patch by Tyler Doyle.
  • Issue #16550: Update the opcode descriptions of pickletools to use unsigned integers where appropriate. Initial patch by Serhiy Storchaka.
  • IDLE:
  • Issue #17838: Allow sys.stdin to be reassigned.
  • Issue #13495: Avoid loading the color delegator twice in IDLE.
  • Issue #17798: Allow IDLE to edit new files when specified on command line.
  • Issue #14735: Update IDLE docs to omit “Control-z on Windows”.
  • Issue #17585: Fixed IDLE regression. Now closes when using exit() or quit().
  • Issue #17657: Show full Tk version in IDLE’s about dialog. Patch by Todd Rovito.
  • Issue #17613: Prevent traceback when removing syntax colorizer in IDLE.
  • Issue #1207589: Backwards-compatibility patch for right-click menu in IDLE.
  • Issue #16887: IDLE now accepts Cancel in tabify/untabify dialog box.
  • Issue #17625: In IDLE, close the replace dialog after it is used.
  • Issue #14254: IDLE now handles readline correctly across shell restarts.
  • Issue #17614: IDLE no longer raises exception when quickly closing a file.
  • Issue #6698: IDLE now opens just an editor window when configured to do so.
  • Issue #8900: Using keyboard shortcuts in IDLE to open a file no longer raises an exception.
  • Issue #6649: Fixed missing exit status in IDLE. Patch by Guilherme Polo.
  • Tests:
  • Issue #17833: Fix test_gdb failures seen on machines where debug symbols for glibc are available (seen on PPC64 Linux).
  • Issue #7855: Add tests for ctypes/winreg for issues found in IronPython. Initial patch by Dino Viehland.
  • Issue #17712: Fix test_gdb failures on Ubuntu 13.04.
  • Issue #17835: Fix test_io when the default OS pipe buffer size is larger than one million bytes.
  • Issue #17065: Use process-unique key for winreg tests to avoid failures if test is run multiple times in parallel (eg: on a buildbot host).
  • Issue #12820: add tests for the xml.dom.minicompat module. Patch by John Chandler and Phil Connell.
  • Issue #17790: test_set now works with unittest test discovery. Patch by Zachary Ware.
  • Issue #17789: test_random now works with unittest test discovery. Patch by Zachary Ware.
  • Issue #17779: test_osx_env now works with unittest test discovery. Patch by Zachary Ware.
  • Issue #17766: test_iterlen now works with unittest test discovery. Patch by Zachary Ware.
  • Issue #17690: test_time now works with unittest test discovery. Patch by Zachary Ware.
  • Issue #17692: test_sqlite now works with unittest test discovery. Patch by Zachary Ware.
  • Issue #17843: Removed bz2 test data file that was triggering false-positive virus warnings with certain antivirus software.
  • Documentation:
  • Issue #15940: Specify effect of locale on time functions.
  • Issue #6696: add documentation for the Profile objects, and improve profile/cProfile docs. Patch by Tom Pinckney.
  • Issue #17915: Fix interoperability of xml.sax with file objects returned by codecs.open().
  • Build:
  • Issue #17547: In configure, explicitly pass -Wformat for the benefit for GCC 4.8.
  • Issue #17962: Build with OpenSSL 1.0.1e on Windows.

New in version 3.3.1 (April 8th, 2013)

  • Build:
  • Issue #17550: Fix the –enable-profiling configure switch.
  • Library:
  • Issue #17625: In IDLE, close the replace dialog after it is used.

New in version 3.3.1 RC 1 (March 26th, 2013)

  • PEP 380, syntax for delegating to a subgenerator (yield from)
  • PEP 393, flexible string representation (doing away with the distinction between "wide" and "narrow" Unicode builds)
  • A C implementation of the "decimal" module, with up to 120x speedup for decimal-heavy applications
  • The import system (__import__) is based on importlib by default
  • The new "lzma" module with LZMA/XZ support
  • PEP 397, a Python launcher for Windows
  • PEP 405, virtual environment support in core
  • PEP 420, namespace package support
  • PEP 3151, reworking the OS and IO exception hierarchy
  • PEP 3155, qualified name for classes and functions
  • PEP 409, suppressing exception context
  • PEP 414, explicit Unicode literals to help with porting
  • PEP 418, extended platform-independent clocks in the "time" module
  • PEP 412, a new key-sharing dictionary implementation that significantly saves memory for object-oriented code
  • PEP 362, the function-signature object
  • The new "faulthandler" module that helps diagnosing crashes
  • The new "unittest.mock" module
  • The new "ipaddress" module
  • The "sys.implementation" attribute
  • A policy framework for the email package, with a provisional (see PEP 411) policy that adds much improved unicode support for email header parsing
  • A "collections.ChainMap" class for linking mappings to a single unit
  • Wrappers for many more POSIX functions in the "os" and "signal" modules, as well as other useful functions such as "sendfile()"
  • Hash randomization, introduced in earlier bugfix releases, is now switched on by default

New in version 3.3.0 (September 30th, 2012)

  • New syntax features:
  • New yield from expression for generator delegation.
  • The u'unicode' syntax is accepted again for str objects.
  • New library modules:
  • faulthandler (helps debugging low-level crashes)
  • ipaddress (high-level objects representing IP addresses and masks)
  • lzma (compress data using the XZ / LZMA algorithm)
  • unittest.mock (replace parts of your system under test with mock objects)
  • venv (Python virtual environments, as in the popular virtualenv package)
  • New built-in features:
  • Reworked I/O exception hierarchy.
  • Implementation improvements:
  • Rewritten import machinery based on importlib.
  • More compact unicode strings.
  • More compact attribute dictionaries.
  • Significantly Improved Library Modules:
  • C Accelerator for the decimal module.
  • Better unicode handling in the email module (provisional).
  • Security improvements:
  • Hash randomization is switched on by default.

New in version 3.3.0 RC 3 (September 25th, 2012)

  • New syntax features:
  • New yield from expression for generator delegation.
  • The u'unicode' syntax is accepted again for str objects.
  • New library modules:
  • faulthandler (helps debugging low-level crashes)
  • ipaddress (high-level objects representing IP addresses and masks)
  • lzma (compress data using the XZ / LZMA algorithm)
  • unittest.mock (replace parts of your system under test with mock objects)
  • venv (Python virtual environments, as in the popular virtualenv package)
  • New built-in features:
  • Reworked I/O exception hierarchy.
  • Implementation improvements:
  • Rewritten import machinery based on importlib.
  • More compact unicode strings.
  • More compact attribute dictionaries.
  • Security improvements:
  • Hash randomization is switched on by default.

New in version 3.3.0 RC 2 (September 12th, 2012)

  • New syntax features:
  • New yield from expression for generator delegation.
  • The u'unicode' syntax is accepted again for str objects.
  • New library modules:
  • faulthandler (helps debugging low-level crashes)
  • ipaddress (high-level objects representing IP addresses and masks)
  • lzma (compress data using the XZ / LZMA algorithm)
  • venv (Python virtual environments, as in the popular virtualenv package)
  • New built-in features:
  • Reworked I/O exception hierarchy.
  • Implementation improvements:
  • Rewritten import machinery based on importlib.
  • More compact unicode strings.
  • More compact attribute dictionaries.
  • Security improvements:
  • Hash randomization is switched on by default.

New in version 3.3.0 Beta 1 (June 27th, 2012)

  • PEP 380, syntax for delegating to a subgenerator ("yield from")
  • PEP 393, flexible string representation (doing away with the distinction between "wide" and "narrow" Unicode builds)
  • A C implementation of the "decimal" module, with up to 80x speedup for decimal-heavy applications
  • The import system (__import__) now based on importlib by default
  • The new "lzma" module with LZMA/XZ support
  • PEP 397, a Python launcher for Windows
  • PEP 405, virtual environment support in core
  • PEP 420, namespace package support
  • PEP 3151, reworking the OS and IO exception hierarchy
  • PEP 3155, qualified name for classes and functions
  • PEP 409, suppressing exception context
  • PEP 414, explicit Unicode literals to help with porting
  • PEP 418, extended platform-independent clocks in the "time" module
  • PEP 412, a new key-sharing dictionary implementation that significantly saves memory for object-oriented code
  • PEP 362, the function-signature object
  • The new "faulthandler" module that helps diagnosing crashes
  • The new "unittest.mock" module
  • The new "ipaddress" module
  • The "sys.implementation" attribute
  • A policy framework for the email package, with a provisional (see PEP 411) policy that adds much improved unicode support for email header parsing
  • A "collections.ChainMap" class for linking mappings to a single unit
  • Wrappers for many more POSIX functions in the "os" and "signal" modules, as well as other useful functions such as "sendfile()"
  • Hash randomization, introduced in earlier bugfix releases, is now switched on by default

New in version 3.3.0 Alpha 4 (June 6th, 2012)

  • New packaging infrastructure
  • PEP 3118: New memoryview implementation and buffer protocol documentation
  • PEP 393: Flexible String Representation
  • PEP 3151: Reworking the OS and IO exception hierarchy
  • PEP 380: Syntax for Delegating to a Subgenerator
  • PEP 409: Suppressing exception context
  • PEP 414: Explicit Unicode literals
  • PEP 3155: Qualified name for classes and functions
  • Using importlib as the Implementation of Import
  • New Email Package Features
  • Other Language Changes
  • A Finer-Grained Import Lock
  • New and Improved Modules
  • Optimizations
  • Build and C API Changes
  • Porting to Python 3.3

New in version 3.2.3 (April 12th, 2012)

  • Work around a problem building extension modules under Windows 14 by undefining ``small`` before use in the Python headers.

New in version 3.2.3 RC2 (March 19th, 2012)

  • Library:
  • Issue #6884: Fix long-standing bugs with MANIFEST.in parsing in distutils on Windows.
  • Extension Modules:
  • Issue #14234: CVE-2012-0876: Randomize hashes of xml attributes in the hash table internal to the pyexpat module's copy of the expat library to avoid a denial of service due to hash collisions. Patch by David Malcolm with some modifications by the expat project.

New in version 3.3.0 Alpha 1 (March 5th, 2012)

  • Syntax for Delegating to a Subgenerator (yield from)
  • Flexible String Representation (doing away with the distinction between "wide" and "narrow" Unicode builds)
  • Suppressing Exception Context
  • Reworking the OS and IO exception hierarchy
  • The new "packaging" module, building upon the "distribute" and "distutils2" projects and deprecating "distutils"
  • The new "lzma" module with LZMA/XZ support
  • Qualified name for classes and functions
  • Explicit Unicode literals to help with porting
  • The new "faulthandler" module that helps diagnosing crashes
  • Wrappers for many more POSIX functions in the "os" and "signal" modules, as well as other useful functions such as "sendfile()"

New in version 3.2.2 (September 5th, 2011)

  • Fixes a regression in the urllib.request module that prevented opening many HTTP resources correctly with Python 3.2.1.

New in version 3.2.2 RC1 (August 16th, 2011)

  • numerous improvements to the unittest module
  • PEP 3147, support for .pyc repository directories
  • PEP 3149, support for version tagged dynamic libraries
  • PEP 3148, a new futures library for concurrent programming
  • PEP 384, a stable ABI for extension modules
  • PEP 391, dictionary-based logging configuration
  • an overhauled GIL implementation that reduces contention
  • an extended email package that handles bytes messages
  • a much improved ssl module with support for SSL contexts and certificate hostname matching
  • a sysconfig module to access configuration information
  • additions to the shutil module, among them archive file support
  • many enhancements to configparser, among them mapping protocol support
  • improvements to pdb, the Python debugger
  • countless fixes regarding bytes/string issues; among them full support for a bytes environment (filenames, environment variables)
  • many consistency and behavior fixes for numeric operations

New in version 3.2.1 (July 11th, 2011)

  • numerous improvements to the unittest module
  • PEP 3147, support for .pyc repository directories
  • PEP 3149, support for version tagged dynamic libraries
  • PEP 3148, a new futures library for concurrent programming
  • PEP 384, a stable ABI for extension modules
  • PEP 391, dictionary-based logging configuration
  • an overhauled GIL implementation that reduces contention
  • an extended email package that handles bytes messages
  • a much improved ssl module with support for SSL contexts and certificate hostname matching
  • a sysconfig module to access configuration information
  • additions to the shutil module, among them archive file support
  • many enhancements to configparser, among them mapping protocol support
  • improvements to pdb, the Python debugger
  • countless fixes regarding bytes/string issues; among them full support for a bytes environment (filenames, environment variables)
  • many consistency and behavior fixes for numeric operations

New in version 3.2.1 RC2 (July 4th, 2011)

  • numerous improvements to the unittest module
  • PEP 3147, support for .pyc repository directories
  • PEP 3149, support for version tagged dynamic libraries
  • PEP 3148, a new futures library for concurrent programming
  • PEP 384, a stable ABI for extension modules
  • PEP 391, dictionary-based logging configuration
  • an overhauled GIL implementation that reduces contention
  • an extended email package that handles bytes messages
  • a much improved ssl module with support for SSL contexts and certificate hostname matching
  • a sysconfig module to access configuration information
  • additions to the shutil module, among them archive file support
  • many enhancements to configparser, among them mapping protocol support
  • improvements to pdb, the Python debugger
  • countless fixes regarding bytes/string issues; among them full support for a bytes environment (filenames, environment variables)
  • many consistency and behavior fixes for numeric operations

New in version 3.2 Beta 1 (December 8th, 2010)

  • numerous improvements to the unittest module
  • PEP 3147, support for .pyc repository directories
  • PEP 3149, support for version tagged dynamic libraries
  • PEP 3148, a new futures library for concurrent programming
  • PEP 384, a stable ABI for extension modules
  • PEP 391, dictionary-based logging configuration
  • an overhauled GIL implementation that reduces contention
  • an extended email package that handles bytes messages
  • countless fixes regarding bytes/string issues; among them full support for a bytes environment (filenames, environment variables)
  • many consistency and behavior fixes for numeric operations
  • a sysconfig module to access configuration information
  • a pure-Python implementation of the datetime module
  • additions to the shutil module, among them archive file support
  • improvements to pdb, the Python debugger

New in version 3.1.3 (November 29th, 2010)

  • Core and Builtins:
  • Issue #10391: Don't dereference invalid memory in error messages in the ast module.
  • Library:
  • Issue #10459: Update CJK character names to Unicode 5.1.
  • Issue #10092: Properly reset locale in calendar.Locale*Calendar classes.
  • Issue #6098: Don't claim DOM level 3 conformance in minidom.
  • Issue #5762: Fix AttributeError raised by ``xml.dom.minidom`` when an empty XML namespace attribute is encountered.
  • Issue #1710703: Write structures for an empty ZIP archive when a ZipFile is created in modes 'a' or 'w' and then closed without adding any files. Raise BadZipfile (rather than IOError) when opening small non-ZIP files.
  • Issue #4493: urllib.request adds '/' in front of path components which does not start with '/. Common behavior exhibited by browsers and other clients.
  • Issue #6378: idle.bat now runs with the appropriate Python version rather than the system default. Patch by Sridhar Ratnakumar.
  • Issue #10407: Fix two NameErrors in distutils.
  • Issue #10198: fix duplicate header written to wave files when writeframes() is called without data.
  • Issue #10467: Fix BytesIO.readinto() after seeking into a position after the end of the file.
  • Issue #1682942: configparser supports alternative option/value delimiters.
  • Build:
  • Backport r83399 to allow test_distutils to pass on installed versions.
  • Issue #1303434: Generate ZIP file containing all PDBs (already done for rc1).
  • Stop packaging versioncheck tool (already done for rc1).
  • Accept Oracle Berkeley DB 4.8, 5.0 and 5.1 as backend for the dbm extension.
  • Tests:
  • Issue #9424: Replace deprecated assert* methods in the Python test suite.
  • Documentation:
  • Issue #10299: List the built-in functions in a table in functions.rst.

New in version 3.1.2 (March 22nd, 2010)

  • Core and Builtins:
  • Issue #7173: Generator finalization could invalidate sys.exc_info().
  • Library:
  • Issue #2698: The --compiler ignored was ignored for distutils' build_ext.
  • Issue #4961: Inconsistent/wrong result of askyesno function in tkMessageBox with Tcl/Tk-8.5.
  • Issue #7356: ctypes.util: Make parsing of ldconfig output independent of the locale.

New in version 3.1.1 (August 17th, 2009)

  • Core and Builtins:
  • Issue #6707: dir() on an uninitialized module caused a crash.
  • Issue #6540: Fixed crash for bytearray.translate() with invalid parameters.
  • Issue #6573: set.union() stopped processing inputs if an instance of self occurred in the argument chain.
  • Issue #6070: On posix platforms import no longer copies the execute bit from the .py file to the .pyc file if it is set.
  • Issue #6428: Since Python 3.0, the __bool__ method must return a bool object, and not an int. Fix the corresponding error message, and the documentation.
  • Issue #6347: Include inttypes.h as well as stdint.h in pyport.h. This fixes a build failure on HP-UX: int32_t and uint32_t are defined in inttypes.h instead of stdint.h on that platform.
  • Issue #6373: Fixed a SystemError when encoding with the latin-1 codec and the 'surrogateescape' error handler, a string which contains unpaired surrogates.
  • C-API:
  • Issue #6624: yArg_ParseTuple with "s" format when parsing argument with NUL: Bogus TypeError detail string.
  • Issue #6405: Remove duplicate type declarations in descrobject.h.
  • The code flags for old __future__ features are now available again.
  • Library:
  • Issue #6106: telnetlib.Telnet.process_rawq doesn't handle default WILL/WONT DO/DONT correctly.
  • Issue #6126: Fixed pdb command-line usage.
  • Issue #6629: Fix a data corruption issue in the new I/O library, which could occur when writing to a BufferedRandom object (e.g. a file opened in "rb+" or "wb+" mode) after having buffered a certain amount of data for reading. This bug was not present in the pure Python implementation.
  • Issue #6622: Fix "local variable 'secret' referenced before assignment" bug in POP3.apop.
  • Issue #6637: defaultdict.copy() did not work when the default factory was left unspecified. Also, the eval/repr round-trip would fail when the default_factory was None.
  • Issue #2715: Remove remnants of Carbon.File from binhex module.
  • Issue #6595: The Decimal constructor now allows arbitrary Unicode decimal digits in input, as recommended by the standard. Previously it was restricted to accepting [0-9].
  • Issues #5155, #5313, #5331: multiprocessing.Process._bootstrap was unconditionally calling "os.close(sys.stdin.fileno())" resulting in file descriptor errors
  • Issue #1424152: Fix for http.client, urllib.request to support SSL while working through proxy. Original patch by Christopher Li, changes made by Senthil Kumaran
  • importlib.abc.PyLoader did not inherit from importlib.abc.ResourceLoader like the documentation said it did even though the code in PyLoader relied on the abstract method required by ResourceLoader.
  • Issue #6431: Make Fraction type return NotImplemented when it doesn't know how to handle a comparison without loss of precision. Also add correct handling of infinities and nans for comparisons with float.
  • Issue #6415: Fixed warnings.warn segfault on bad formatted string.
  • Issue #6358: The exit status of a command started with os.popen() was reported differently than it did with python 2.x.
  • Issue #6323: The pdb debugger did not exit when running a script with a syntax error.
  • Issue #3392: The subprocess communicate() method no longer fails in select() when file descriptors are large; communicate() now uses poll() when possible.
  • Issue #6369: Fix an RLE decompression bug in the binhex module.
  • Issue #6344: Fixed a crash of mmap.read() when passed a negative argument.
  • Issue #4005: Fixed a crash of pydoc when there was a zip file present in sys.path.
  • Extension Modules:
  • Fix a segfault in expat.
  • Issue #4509: array.array objects are no longer modified after an operation failing due to the resize restriction in-place when the object has exported buffers.
  • Build:
  • Issue 4601: 'make install' did not set the appropriate permissions on directories.
  • Issue 5390: Add uninstall icon independent of whether file extensions are installed.
  • Test:
  • Fix a test in importlib.test.source.test_abc_loader that was incorrectly testing when a .pyc file lacked an code object bytecode.

New in version 3.1 (June 29th, 2009)

  • Core and Builtins:
  • Issue #6334: Fix bug in range length calculation for ranges with large arguments.
  • Issue #6329: Fixed iteration for memoryview objects (it was being blocked because it wasn't recognized as a sequence).
  • Library:
  • Issue #6314: logging.basicConfig() performs extra checks on the "level" argument.
  • Issue #6274: Fixed possible file descriptors leak in subprocess.py
  • Accessing io.StringIO.buffer now raises an AttributeError instead of io.UnsupportedOperation.
  • Issue #6271: mmap tried to close invalid file handle (-1) when anonymous. (On Unix)
  • Issue #1202: zipfile module would cause a struct.error when attempting to store files with a CRC32 > 2**31-1.
  • Extension Modules
  • Issue #5590: Remove unused global variable in pyexpat extension.

New in version 3.1 RC 2 (June 15th, 2009)

  • Core and Builtins:
  • Fixed SystemError triggered by "range([], 1, -1)".
  • Issue #5924: On Windows, a large PYTHONPATH environment variable (more than 255 characters) would be completely ignored.
  • Issue #4547: When debugging a very large function, it was not always possible to update the lineno attribute of the current frame.
  • Issue #5330: C functions called with keyword arguments were not reported by the various profiling modules (profile, cProfile). Patch by Hagen Fürstenau.
  • Library:
  • Issue #6258: Support AMD64 in bdist_msi.
  • Issue #6195: fixed doctest to no longer try to read 'source' data from binary files.
  • Issue #5262: Fixed bug in next rollover time computation in TimedRotatingFileHandler.
  • Issue #6217: The C implementation of io.TextIOWrapper didn't include the errors property. Additionally, the errors and encoding properties of StringIO are always None now.
  • Issue #6137: The pickle module now translates module names when loading or dumping pickles with a 2.x-compatible protocol, in order to make data sharing and migration easier. This behaviour can be disabled using the new `fix_imports` optional argument.
  • Removed the ipaddr module.
  • Issue #3613: base64.{encode,decode}string are now called base64.{encode,decode}bytes which reflects what type they accept and return.
  • The old names are still there as deprecated aliases.
  • Issue #5767: Remove sgmlop support from xmlrpc.client.
  • Issue #6150: Fix test_unicode on wide-unicode builds.
  • Issue #6149: Fix initialization of WeakValueDictionary objects from non-empty parameters.
  • C-API:
  • Issue #5735: Python compiled with --with-pydebug should throw an ImportError when trying to import modules compiled without--with-pydebug, and vice-versa.
  • Build:
  • Issue #6154: Make sure the intl library is added to LIBS if needed. Also added LIBS to OS X framework builds.
  • Issue #5809: Specifying both --enable-framework and --enable-shared is an error. Configure now explicity tells you about this.

New in version 3.1 Alpha 2 (April 16th, 2009)

  • Core and Builtins:
  • Implement PEP 378, Format Specifier for Thousands Separator, for integers.
  • Issue #5666: Py_BuildValue's 'c' code should create byte strings.
  • Issue #5499: The 'c' code for argument parsing functions now only accepts a byte, and the 'C' code only accepts a unicode character.
  • Issue #1665206: Remove the last eager import in _warnings.c and make it lazy.
  • Fix a segfault when running test_exceptions with coverage, caused by insufficient checks in accessors of Exception.__context__.
  • Issue #5604: non-ASCII characters in module name passed to imp.find_module() were converted to UTF-8 while the path is converted to the default filesystem encoding, causing nonsense.
  • Issue #5126: str.isprintable() returned False for space characters.
  • Issue #4865: On MacOSX /Library/Python/2.7/site-packages is added to the end sys.path, for compatibility with the system install of Python.
  • Issue #4688: Add a heuristic so that tuples and dicts containing only untrackable objects are not tracked by the garbage collector. This can reduce the size of collections and therefore the garbage collection overhead on long-running programs, depending on their particular use of datatypes.
  • Issue #5512: Rewrite PyLong long division algorithm (x_divrem) to improve its performance. Long divisions and remainder operations are now between 50% and 150% faster.
  • Issue #4258: Make it possible to use base 2**30 instead of base 2**15 for the internal representation of integers, for performance reasons. Base 2**30 is enabled by default on 64-bit machines. Add --enable-big-digits option to configure, which overrides the default. Add sys.int_info structseq to provide information about the internal format.
  • Issue #4474: PyUnicode_FromWideChar now converts characters outside the BMP to surrogate pairs, on systems with sizeof(wchar_t) == 4 and sizeof(Py_UNICODE) == 2.
  • Issue #5237: Allow auto-numbered fields in str.format(). For example: '{} {}'.format(1, 2) == '1 2'.
  • Issue #5392: when a very low recursion limit was set, the interpreter would abort with a fatal error after the recursion limit was hit twice.
  • Issue #3845: In PyRun_SimpleFileExFlags avoid invalid memory access with short file names.
  • Py_DECREF: Add `do { ... } while (0)' to avoid compiler warnings.
  • Library:
  • Issue 2625: added missing items() call to the for loop in mailbox.MH.get_message().
  • Issue #5640: Fix _multibytecodec so that CJK codecs don't repeat error substitutions from non-strict codec error callbacks in incrementalencoder and StreamWriter.
  • Issue #5656: Fix the coverage reporting when running the test suite with the -T argument.
  • Issue #5647: MutableSet.__iand__() no longer mutates self during iteration.
  • Issue #5624: Fix the _winreg module name still used in several modules.
  • Issue #5628: Fix io.TextIOWrapper.read() with a unreadable buffer.
  • Issue #5619: Multiprocessing children disobey the debug flag and causes popups on windows buildbots. Patch applied to work around this issue.
  • Issue #5400: Added patch for multiprocessing on netbsd compilation/support
  • Issue #5387: Fixed mmap.move crash by integer overflow.
  • Issue #5261: Patch multiprocessing's semaphore.c to support context manager use: "with multiprocessing.Lock()" works now.
  • Issue #5236: Change time.strptime() to only take strings. Didn't work with bytes already but the failure was non-obvious.
  • Issue #5177: Multiprocessing's SocketListener class now uses socket.SO_REUSEADDR on all connections so that the user no longer needs to wait 120 seconds for the socket to expire.
  • Issue #5595: Fix UnboundedLocalError in ntpath.ismount().
  • Issue #1174606: Calling read() without arguments of an unbounded file (typically /dev/zero under Unix) could crash the interpreter.
  • The max_buffer_size arguments of io.BufferedWriter, io.BufferedRWPair, and io.BufferedRandom have been deprecated for removal in Python 3.2.
  • Issue #5068: Fixed the tarfile._BZ2Proxy.read() method that would loop forever on incomplete input. That caused tarfile.open() to hang when used with mode 'r' or 'r:bz2' and a fileobj argument that contained no data or partial bzip2 compressed data.
  • Issue #2110: Add support for thousands separator and 'n' type specifier to Decimal.__format__
  • Fix Decimal.__format__ bug that swapped the meanings of the '' alignment characters.
  • The error detection code in FileIO.close() could fail to reflect the `errno` value, and report it as -1 instead.
  • Issue #5016: FileIO.seekable() could return False if the file position was negative when truncated to a C int. Patch by Victor Stinner.
  • Extension Modules:
  • Issue #5391: mmap now deals exclusively with bytes.
  • Issue #5463: In struct module, remove deprecated overflow wrapping when packing an integer: struct.pack('=L', -1) now raises struct.error instead of returning b'xffxffxffxff'. The _PY_STRUCT_RANGE_CHECKING and _PY_STRUCT_OVERFLOW_MASKING constants have been removed from the struct module.

New in version 2.6.1 (December 6th, 2008)

  • Core and Builtins:
  • Issue #3996: On Windows, the PyOS_CheckStack function would cause the interpreter to abort ("Fatal Python error: Could not reset the stack!") instead of throwing a MemoryError.
  • Issue #4367: Python would segfault during compiling when the unicodedata module couldn't be imported and N escapes were present.
  • Issue #4348: Some bytearray methods returned that didn't cause any change to the bytearray, returned the same bytearray instead of a copy.
  • Issue #4317: Fixed a crash in the imageop.rgb2rgb8() function.
  • Issue #4230: If ``__getattr__`` is a descriptor, it now functions correctly.
  • Issue #4048: The parser module now correctly validates relative imports.
  • Issue #4225: ``from __future__ import unicode_literals`` didn't work in an exec statement.
  • Issue #4176: Fixed a crash when pickling an object which ``__reduce__`` method does not return iterators for the 4th and 5th items.
  • Issue #4209: Enabling unicode_literals and the print_function in the same __future__ import didn't work.
  • On windows, os.chdir given unicode was not working if GetCurrentDirectoryW returned a path longer than MAX_PATH. (But It's doubtful this code path is really executed because I cannot move to such directory on win2k)
  • Issue #4069: When set.remove(element) is used with a set element, the element is temporarily replaced with an equivalent frozenset. But the eventual KeyError would always report the empty frozenset([]) as the missing key. Now it correctly refers to the initial element.
  • Fixed C99 style comments in several files. Python is now C89 compatible again.
  • Library:
  • Issue #3741: DISTUTILS_USE_SDK set causes msvc9compiler.py to raise an exception.
  • Issue #4363: The uuid.uuid1() and uuid.uuid4() functions now work even if the ctypes module is not present.
  • Issue #4116: Resolve member name conflict in ScrolledCanvas.__init__.
  • Issue #3774: Fixed an error when create a Tkinter menu item without command and then remove it.
  • Fixed a modulefinder crash on certain relative imports.
  • Issue #4150: Pdb's "up" command now works for generator frames in post-mortem debugging.
  • Issue #4092: Return ArgInfo as promised in the documentation from inspect.getargvalues.
  • Issue #3935: Properly support list subclasses in bisect's C implementation.
  • Issue #4014: Don't claim that Python has an Alpha release status, in addition to claiming it is Mature.
  • Build:
  • Issue #4389: Add icon to the uninstall entry in "add-and-remove-programs".
  • Issue #4289: Remove Cancel button from AdvancedDlg.
  • Issue #1656675: Register a drop handler for .py* files on Windows.
  • Issue #4120: Exclude manifest from extension modules in VS2008.
  • Issue #4091: Install pythonxy.dll in system32 again.
  • Issue #4018: Disable "for me" installations on Vista.
  • Issue #3758: Add ``patchcheck`` build target to .PHONY.
  • Issue #4204: Fixed module build errors on FreeBSD 4.
  • C-API:
  • Issue #4122: On Windows, fix a compilation error when using the Py_UNICODE_ISSPACE macro in an extension module.
  • Extension Modules:
  • Issue #4365: Add crtassem.h constants to the msvcrt module.
  • Issue #4396: The parser module now correctly validates the with statement.

New in version 3.0 (December 4th, 2008)

  • Core and Builtins:
  • Issue #3996: On Windows, the PyOS_CheckStack function would cause the interpreter to abort ("Fatal Python error: Could not reset the stack!") instead of throwing a MemoryError.
  • Issue #3689: The list reversed iterator now supports __length_hint__ instead of __len__. Behavior now matches other reversed iterators.
  • Issue #4367: Python would segfault during compiling when the unicodedata module couldn't be imported and N escapes were present.
  • Fix build failure of _cursesmodule.c building with -D_FORTIFY_SOURCE=2.
  • Library:
  • Issue #4387: binascii now refuses to accept str as binary input.
  • Issue #4073: Add 2to3 support to build_scripts, refactor that support in build_py.
  • IDLE would print a "Unhandled server exception!" message when internal debugging is enabled.
  • Issue #4455: IDLE failed to display the windows list when two windows have the same title.
  • Issue #3741: DISTUTILS_USE_SDK set causes msvc9compiler.py to raise an exception.
  • Issue #4433: Fixed an access violation when garbage collecting _ctypes.COMError instances.
  • Issue #4429: Fixed UnicodeDecodeError in ctypes.
  • Issue #4373: Corrected a potential reference leak in the pickle module and silenced a false positive ref leak in distutils.tests.test_build_ext.
  • Issue #4382: dbm.dumb did not specify the expected file encoding for opened files.
  • Issue #4383: When IDLE cannot make the connection to its subprocess, it would fail to properly display the error message.
  • Build:
  • Issue #4407: Fix source file that caused the compileall step in Windows installer to fail.
  • Docs:
  • Issue #4449: Fixed multiprocessing examples
  • Issue #3799: Document that dbm.gnu and dbm.ndbm will accept string arguments for keys and values which will be converted to bytes before committal.

New in version 2.6.0 (October 2nd, 2008)

  • Some significant new packages have been added to the standard library, such as the multiprocessing and json modules, but there aren’t many new features that aren’t related to Python 3.0 in some way.
  • Python 2.6 also sees a number of improvements and bugfixes throughout the source. A search through the change logs finds there were 259 patches applied and 612 bugs fixed between Python 2.5 and 2.6. Both figures are likely to be underestimates.

New in version 2.5.2 (February 25th, 2008)

  • Fix deallocation of array objects when allocation ran out of memory. Remove array test case that was incorrect on 64-bit systems.
  • Bug #2137: Remove test_struct.test_crasher, which was meaningful only on 32-bit systems.

New in version 2.5.2 RC1 (February 19th, 2008)

  • Added checks for integer overflows, contributed by Google. Some are only available if asserts are left in the code, in cases where they can't be triggered from Python code.
  • Issue #2045: Fix an infinite recursion triggered when printing a subclass of collections.defaultdict, if its default_factory is set to a bound method.
  • Issue #1920: "while 0" statements were completely removed by the compiler, even in the presence of an "else" clause, which is supposed to be run when the condition is false. Now the compiler correctly emits bytecode for the "else" suite.
  • A few crashers fixed: weakref_in_del.py (issue #1377858); loosing_dict_ref.py (issue #1303614, test67.py); borrowed_ref_[34].py (not in tracker).
  • Fix for #1303614 and #1174712 backported from the trunk: __dict__ descriptor abuse for subclasses of built-in types; subclassing from both ModuleType and another built-in types.
  • Bug #1915: Python compiles with --enable-unicode=no again. However several extension methods and modules do not work without unicode support.
  • Issue #1678380: distinction between 0.0 and -0.0 was lost during constant folding optimization. This was a regression from Python 2.4.
  • Issue #1882: when compiling code from a string, encoding cookies in the second line of code were not always recognized correctly.
  • Bug #1517: Possible segfault in lookup().
  • Issue #1638: %zd configure test fails on Linux.
  • Issue #1553: An erroneous __length_hint__ can make list() raise a SystemError.
  • Issue #1521: On 64bit platforms, using PyArgs_ParseTuple with the t# of w# format code incorrectly truncated the length to an int, even when PY_SSIZE_T_CLEAN is set. The str.decode method used to return incorrect results with huge strings.
  • Issue #1445: Fix a SystemError when accessing the ``cell_contents`` attribute of an empty cell object.
  • Issue #1265: Fix a problem with sys.settrace, if the tracing function uses a generator expression when at the same time the executed code is closing a paused generator.
  • Issue 1704621: Fix segfaults in list_repeat() and list_inplace_repeat().
  • Issue #1147: Generators were not raising a DeprecationWarning when a string was passed into throw().
  • Patch #1031213: Decode source line in SyntaxErrors back to its original source encoding.
  • Patch #1673759: add a missing overflow check when formatting floats with %G.
  • Patch #1733960: Allow T_LONGLONG to accept ints.
  • Prevent expandtabs() on string and unicode objects from causing a segfault when a large width is passed on 32-bit platforms.
  • Bug #1733488: Fix compilation of bufferobject.c on AIX.
  • Fix Issue #1703448: A joined thread could show up in the threading.enumerate() list after the join() for a brief period until it actually exited.
  • Patch #1966: Break infinite loop in httplib when the servers implements the chunked encoding incorrectly.
  • tarfile.py: Fix reading of xstar archives.
  • #2021: Allow tempfile.NamedTemporaryFile to be used in with statements by correctly supporting the context management protocol.
  • Fixed _ctypes.COMError so that it must be called with exactly three arguments, instances now have the hresult, text, and details instance variables.
  • #1507247, #2004: tarfile.py: Use mode 0700 for temporary directories and default permissions for missing directories.
  • #175006: The debugger used to skip the condition of a "while" statement after the first iteration. Now it correctly steps on the expression, and breakpoints on the "while" statement are honored on each loop.
  • The ctypes int types did not accept objects implementing __int__() in the constructor.
  • #1189216: Fix the zipfile module to work on archives with headers past the 2**31 byte boundary.
  • Issue #1336: fix a race condition in subprocess.Popen if the garbage collector kicked in at the wrong time that would cause the process to hang when the child wrote to stderr.
  • Bug #1687: Fixed plistlib.py restricts to Python int when writing.
  • Issue #1182: many arithmetic bugs in the decimal module have been fixed, and the decimal module has been updated to comply with the latest IBM Decimal Arithmetic specification (version 1.66) and testsuite (version 2.57). (Backported from Python 2.6a0.)
  • Patch #1637: fix urlparse for URLs like 'http://x.com?arg=/foo'.
  • Issue #1735: TarFile.extractall() now correctly sets directory permissions and times.
  • Bug #1713: posixpath.ismount() claims symlink to a mountpoint is a mountpoint.
  • Issue #1700: Regular expression inline flags incorrectly handle certain unicode characters.
  • Change ctypes version number to 1.0.3 (when Python 2.5.2 is released, ctypes 1.0.3 will be also be released).
  • Issue #1695: Fixed typo in the docstrings for time.localtime() and gmtime().
  • Issue #1642: Fix segfault in ctypes when trying to delete attributes.
  • os.access now returns True on Windows for any existing directory.
  • Issue #1531: tarfile.py: Read fileobj from the current offset, do not seek to the start.
  • Issue 1429818: patch for trace and doctest modules so they play nicely together.
  • doctest mis-used __loader__.get_data(), assuming universal newlines was used.
  • Issue #1705170: contextlib.contextmanager was still swallowing StopIteration in some cases. This should no longer happen.
  • Bug #1307: Fix smtpd so it doesn't raise an exception when there is no arg.
  • ctypes will now work correctly on 32-bit systems when Python is configured with --with-system-ffi.
  • Bug #1777530: ctypes.util.find_library uses dump(1) instead of objdump(1) on Solaris.
  • Bug #1153: repr.repr() now doesn't require set and dictionary items to be orderable to properly represent them.
  • Bug #1709599: Run test_1565150 only if the file system is NTFS.
  • When encountering a password-protected robots.txt file the RobotFileParser no longer prompts interactively for a username and password (bug 813986).
  • TarFile.__init__() no longer fails if no name argument is passed and the fileobj argument has no usable name attribute (e.g. StringIO).
  • Reverted the fix for bug #1548891 because it broke compatibility with arbitrary read buffers. Added a note in the documentation.
  • GB18030 codec now can encode additional two-byte characters that are missing in GBK.
  • Bug #1704793: Raise KeyError if unicodedata.lookup cannot represent the result in a single character.
  • Change location of the package index to pypi.python.org/pypi
  • Bug #1701409: Fix a segfault in printing ctypes.c_char_p and ctypes.c_wchar_p when they point to an invalid location. As a sideeffect the representation of these instances has changed.
  • Bug #1734723: Fix repr.Repr() so it doesn't ignore the maxtuple attribute.
  • Bug #1728403: Fix a bug that CJKCodecs StreamReader hangs when it reads a file that ends with incomplete sequence and sizehint argument for .read() is specified.
  • Bug #1730389: Have time.strptime() match spaces in a format argument with ``s `` instead of ``s*``.
  • SF 1668596/1720897: distutils now copies data files even if package_dir is empty.
  • Fix bug in marshal where bad data would cause a segfault due to lack of an infinite recursion check.
  • mailbox.py: Ignore stray directories found in Maildir's cur/new/tmp subdirectories.
  • HTML-escape the plain traceback in cgitb's HTML output, to prevent the traceback inadvertently or maliciously closing the comment and injecting HTML into the error page.
  • Bug #1290505: Properly clear time.strptime's locale cache when the locale changes between calls. Backport of r54646 and r54647.
  • Bug #1706381: Specifying the SWIG option "-c " in the setup.py file (as opposed to the command line) will now write file names ending in ".cpp" too.
  • Patch #1695229: Fix a regression with tarfile.open() and a missing name argument.
  • tarfile.py: Fix directory names to have only one trailing slash.
  • Fix test_pty.py to not hang on OS X (and theoretically other *nixes) when run in verbose mode.
  • Bug #1693258: IDLE would show two "Preferences" menu's with some versions of Tcl/Tk
  • Issue1385: The hmac module now computes the correct hmac when using hashes with a block size other than 64 bytes (such as sha384 and sha512).
  • Issue829951: In the smtplib module, SMTP.starttls() now complies with RFC 3207 and forgets any knowledge obtained from the server not obtained from the TLS negotiation itself. Patch contributed by Bill Fenner.
  • Patch #1736: Fix file name handling of _msi.FCICreate.
  • Backport r59862 (issue #712900): make long regexp matches interruptable.
  • #1940: make it possible to use curses.filter() before curses.initscr() as the documentation says.
  • Fix a potential 'SystemError: NULL result without error' in _ctypes.
  • Bug #1301: Bad assert in _tkinter fixed.
  • Patch #1114: fix curses module compilation on 64-bit AIX, & possibly other 64-bit LP64 platforms where attr_t is not the same size as a long. (Contributed by Luke Mewburn.)
  • Bug #1649098: Avoid declaration of zero-sized array declaration in structure.
  • Bug #1703286: ctypes no longer truncates 64-bit pointers.
  • Bug #1721309: prevent bsddb module from freeing random memory.
  • Bug #1233: fix bsddb.dbshelve.DBShelf append method to work as intended for RECNO databases.
  • Bug #1726026: Correct the field names of WIN32_FIND_DATAA and WIN32_FIND_DATAW structures in the ctypes.wintypes module.
  • Added support for linking the bsddb module against BerkeleyDB 4.6.x.
  • Fix libffi configure for hppa*-*-linux* | parisc*-*-linux*.
  • Build using system ffi library on arm*-linux*.
  • Bug #1372: zlibmodule.c: int overflow in PyZlib_decompress
  • bsddb module: Fix memory leak when using database cursors on databases without a DBEnv.
  • Bug #1637365: add subsection about "__name__ == __main__" to the Python tutorial.
  • Bug #1569057: Document that calling file.next() on a file open for writing has undefined behaviour. Backport of r54712.
  • Have the search path for building extensions follow the declared order in $CPPFLAGS and $LDFLAGS.
  • Bug #1234: Fixed semaphore errors on AIX 5.2
  • Bug #1699: Define _BSD_SOURCE only on OpenBSD.
  • Bug #1608: use -fwrapv when GCC supports it. This is important, newer GCC versions may optimize away overflow buffer overflow checks without this option!
  • Allow simultaneous installation of 32-bit and 64-bit versions on 64-bit Windows systems.
  • Patch #786737: Allow building in a tree of symlinks pointing to a readonly source.
  • Bug #1737210: Change Manufacturer of Windows installer to PSF.
  • Bug #1746880: Correctly install DLLs into system32 folder on Win64.
  • Define _BSD_SOURCE, to get access to POSIX extensions on OpenBSD 4.1 .
  • Patch #1673122: Use an explicit path to libtool when building a framework. This avoids picking up GNU libtool from a users PATH.
  • Allow Emacs 22 for building the documentation in info format.
  • Makefile.pre.in(buildbottest): Run an optional script pybuildbot.identify to include some information about the build environment.