Security¶

• bpo-36216: Changes urlsplit() to raise ValueError when the URL containscharacters that decompose under IDNA encoding (NFKC-normalization) intocharacters that affect how the URL is parsed.
• bpo-35121: Don’t send cookies of domain A without Domain attribute todomain B when domain A is a suffix match of domain B while using acookiejar withhttp.cookiejar.DefaultCookiePolicy policy. Patchby Karthikeyan Singaravelan.

Library¶

• bpo-35121: Don’t set cookie for a request when the request path is aprefix match of the cookie’s path attribute but doesn’t end with “/”.Patch by Karthikeyan Singaravelan.

Security¶

• bpo-35746: [CVE-2019-5010] Fix a NULL pointer deref in ssl module. Thecert parser did not handle CRL distribution points with empty DP or URIcorrectly. A malicious or buggy certificate can result into segfault.Vulnerability (TALOS-2018-0758) reported by Colin Read and Nicolas Edet ofCisco.
• bpo-34791: The xml.sax and xml.dom.domreg no longer use environmentvariables to override parser implementations whensys.flags.ignore_environment is set by -E or -I arguments.
• bpo-34623: CVE-2018-14647: The C accelerated _elementtree module nowinitializes hash randomization salt from _Py_HashSecret instead oflibexpat’s default CSPRNG.

Library¶

• bpo-33329: Fix multiprocessing regression on newer glibcs

Security¶

• bpo-33001: Minimal fix to prevent buffer overrun in os.symlink on Windows
• bpo-32981: Regexes in difflib and poplib were vulnerable to catastrophicbacktracking. These regexes formed potential DOS vectors (REDOS). Theyhave been refactored. This resolves CVE-2018-1060 and CVE-2018-1061. Patchby Jamie Davis.

Security¶

• bpo-30657: Fixed possible integer overflow in PyBytes_DecodeEscape,CVE-2017-1000158. Original patch by Jay Bosamiya; rebased to Python 3 byMiro Hrončok.
• bpo-30947: Upgrade libexpat embedded copy from version 2.2.1 to 2.2.3 toget security fixes.
• bpo-29169: Update zlib from 1.2.8 to 1.2.11 to get security fixes.

Library¶

• bpo-32072: Fixed issues with binary plists:
  • Fixed saving bytearrays.
  • Identical objects will be saved only once.
  • Equal references will be load as identical objects.
  • Added support for saving and loading recursive data structures.
• bpo-31170: expat: Update libexpat from 2.2.3 to 2.2.4. Fix copying ofpartial characters for UTF-8 input (libexpat bug 115):https://github.com/libexpat/libexpat/issues/115

Build¶

• bpo-29572: Update Windows build and OS X installers to use OpenSSL 1.0.2k.

Library¶

• bpo-30119: ftplib.FTP.putline() now throws ValueError on commands thatcontains CR or LF. Patch by Dong-hee Na.

Security¶

• bpo-29591: Update expat copy from 2.1.1 to 2.2.0 to get fixes ofCVE-2016-0718 and CVE-2016-4472. Seehttps://sourceforge.net/p/expat/bugs/537/ for more information.
• bpo-30694: Upgrade expat copy from 2.2.0 to 2.2.1 to get fixes of multiplesecurity vulnerabilities including: CVE-2017-9233 (External entityinfinite loop DoS), CVE-2016-9063 (Integer overflow, re-fix),CVE-2016-0718 (Fix regression bugs from 2.2.0’s fix to CVE-2016-0718) andCVE-2012-0876 (Counter hash flooding with SipHash). Note: theCVE-2016-5300 (Use os- specific entropy sources like getrandom) doesn’timpact Python, since Python already gets entropy from the OS to set theexpat secret usingXML_SetHashSalt().
• bpo-26657: Fix directory traversal vulnerability with http.server onWindows. This fixes a regression that was introduced in 3.3.4rc1 and3.4.0rc1. Based on patch by Philipp Hagemeister.
• bpo-30500: Fix urllib.parse.splithost() to correctly parse fragments. Forexample,splithost('//127.0.0.1#@evil.com/') now correctly returns the127.0.0.1 host, instead of treating@evil.com as the host in anauthentification (login@host).
• bpo-30730: Prevent environment variables injection in subprocess onWindows. Prevent passing other invalid environment variables and commandarguments.

Core and Builtins¶

• bpo-26617: Fix crash when GC runs during weakref callbacks.
• bpo-27945: Fixed various segfaults with dict when input collections aremutated during searching, inserting or comparing. Based on patches byDuane Griffin and Tim Mitchell.

Library¶

• bpo-27850: Remove 3DES from ssl module’s default cipher list to countermeasure sweet32 attack (CVE-2016-2183).

Documentation¶

• bpo-25008: Document smtpd.py as effectively deprecated and add a pointerto aiosmtpd, a third-party asyncio-based replacement.

Core and Builtins¶

• bpo-28648: Fixed crash in Py_DecodeLocale() in debug build on Mac OS Xwhen decode astral characters. Patch by Xiang Zhang.
• bpo-28426: Fixed potential crash in PyUnicode_AsDecodedObject() in debugbuild.

Library¶

• bpo-28563: Fixed possible DoS and arbitrary code execution when handleplural form selections in the gettext module. The expression parser nowsupports exact syntax supported by GNU gettext.
• In the curses module, raise an error if window.getstr() or window.instr()is passed a negative value.
• bpo-27783: Fix possible usage of uninitialized memory inoperator.methodcaller.
• bpo-27774: Fix possible Py_DECREF on unowned object in _sre.
• bpo-27760: Fix possible integer overflow in binascii.b2a_qp.
• bpo-27758: Fix possible integer overflow in the _csv module for largerecord lengths.
• bpo-27568: Prevent HTTPoxy attack (CVE-2016-1000110). Ignore theHTTP_PROXY variable when REQUEST_METHOD environment is set, whichindicates that the script is in CGI mode.
• bpo-27759: Fix selectors incorrectly retain invalid file descriptors.Patch by Mark Williams.

Build¶

• bpo-28248: Update Windows build to use OpenSSL 1.0.2j.

Tests¶

• bpo-27369: In test_pyexpat, avoid testing an error message detail thatchanged in Expat 2.2.0.

Tests¶

• bpo-26867: Ubuntu’s openssl OP_NO_SSLv3 is forced on by default; fix test.

Core and Builtins¶

• bpo-26478: Fix semantic bugs when using binary operators with dictionaryviews and tuples.
• bpo-26171: Fix possible integer overflow and heap corruption inzipimporter.get_data().

Library¶

• bpo-26556: Update expat to 2.1.1, fixes CVE-2015-1283.
• Fix TLS stripping vulnerability in smptlib, CVE-2016-0772. Reported byTeam Oststrom
• bpo-25939: On Windows open the cert store readonly inssl.enum_certificates.
• bpo-26012: Don’t traverse into symlinks for ** pattern inpathlib.Path.[r]glob().
• bpo-24120: Ignore PermissionError when traversing a tree withpathlib.Path.[r]glob(). Patch by Ulrich Petri.
• Skip getaddrinfo if host is already resolved. Patch by A. Jesse JiryuDavis.
• Add asyncio.timeout() context manager.
• bpo-26050: Add asyncio.StreamReader.readuntil() method. Patch by МаркКоренберг.

Tests¶

• bpo-25940: Changed test_ssl to use self-signed.pythontest.net. Thisavoids relying on svn.python.org, which recently changed root certificate.

Windows¶

• bpo-25844: Corrected =/== typo potentially leading to crash in launcher.

Core and Builtins¶

• bpo-25709: Fixed problem with in-place string concatenation and utf-8cache.
• bpo-24097: Fixed crash in object.__reduce__() if slot name is freed inside__getattr__.
• bpo-24731: Fixed crash on converting objects with special methods__bytes__, __trunc__, and __float__ returning instances of subclasses ofbytes, int, and float to subclasses of bytes, int, and floatcorrespondingly.
• bpo-25388: Fixed tokenizer crash when processing undecodable source codewith a null byte.
• bpo-22995: Default implementation of __reduce__ and __reduce_ex__ nowrejects builtin types with not defined __new__.
• bpo-24802: Avoid buffer overreads when int(), float(), compile(), exec()and eval() are passed bytes-like objects. These objects are notnecessarily terminated by a null byte, but the functions assumed theywere.
• bpo-24402: Fix input() to prompt to the redirected stdout whensys.stdout.fileno() fails.
• bpo-24806: Prevent builtin types that are not allowed to be subclassedfrom being subclassed through multiple inheritance.
• bpo-24848: Fixed a number of bugs in UTF-7 decoding of misformed data.
• bpo-25280: Import trace messages emitted in verbose (-v) mode are nolonger formatted twice.
• bpo-25003: os.urandom() doesn’t use getentropy() on Solaris becausegetentropy() is blocking, whereas os.urandom() should not block.getentropy() is supported since Solaris 11.3.
• bpo-25182: The stdprinter (used as sys.stderr before the io module isimported at startup) now uses the backslashreplace error handler.
• bpo-24891: Fix a race condition at Python startup if the file descriptorof stdin (0), stdout (1) or stderr (2) is closed while Python is creatingsys.stdin, sys.stdout and sys.stderr objects. These attributes are now setto None if the creation of the object failed, instead of raising anOSError exception. Initial patch written by Marco Paolini.
• bpo-21167: NAN operations are now handled correctly when python iscompiled with ICC even if -fp-model strict is not specified.
• bpo-4395: Better testing and documentation of binary operators. Patch byMartin Panter.
• bpo-24467: Fixed possible buffer over-read in bytearray. The bytearrayobject now always allocates place for trailing null byte and it’s buffernow is always null-terminated.
• bpo-24115: Update uses of PyObject_IsTrue(), PyObject_Not(),PyObject_IsInstance(), PyObject_RichCompareBool() and _PyDict_Contains()to check for and handle errors correctly.
• bpo-24257: Fixed system error in the comparison of fakedtypes.SimpleNamespace.
• bpo-22939: Fixed integer overflow in iterator object. Patch by ClementRouault.
• bpo-23985: Fix a possible buffer overrun when deleting a slice from thefront of a bytearray and then appending some other bytes data.
• bpo-24102: Fixed exception type checking in standard error handlers.
• bpo-23757: PySequence_Tuple() incorrectly called the concrete list APIwhen the data was a list subclass.
• bpo-24407: Fix crash when dict is mutated while being updated.
• bpo-24096: Make warnings.warn_explicit more robust against mutation of thewarnings.filters list.
• bpo-23996: Avoid a crash when a delegated generator raises an unnormalizedStopIteration exception. Patch by Stefan Behnel.
• bpo-24022: Fix tokenizer crash when processing undecodable source code.
• bpo-23309: Avoid a deadlock at shutdown if a daemon thread is abortedwhile it is holding a lock to a buffered I/O object, and the main threadtries to use the same I/O object (typically stdout or stderr). A fatalerror is emitted instead.
• bpo-22977: Fixed formatting Windows error messages on Wine. Patch byMartin Panter.
• bpo-23803: Fixed str.partition() and str.rpartition() when a separator iswider then partitioned string.
• bpo-23192: Fixed generator lambdas. Patch by Bruno Cauet.
• bpo-23629: Fix the default __sizeof__ implementation for variable-sizedobjects.
• bpo-24044: Fix possible null pointer dereference in list.sort in out ofmemory conditions.
• bpo-21354: PyCFunction_New function is exposed by python DLL again.

Library¶

• bpo-24903: Fix regression in number of arguments compileall accepts when‘-d’ is specified. The check on the number of arguments has been droppedcompletely as it never worked correctly anyway.

• bpo-25764: In the subprocess module, preserve any exception caused byfork() failure when preexec_fn is used.

• bpo-6478: _strptime’s regexp cache now is reset after changing timezonewith time.tzset().

• bpo-25177: Fixed problem with the mean of very small and very largenumbers. As a side effect, statistics.mean and statistics.variance shouldbe significantly faster.

• bpo-25718: Fixed copying object with state with boolean value is false.

• bpo-10131: Fixed deep copying of minidom documents. Based on patch byMarian Ganisin.

• bpo-25725: Fixed a reference leak in pickle.loads() when unpicklinginvalid data including tuple instructions.

• bpo-25663: In the Readline completer, avoid listing duplicate globalnames, and search the global namespace before searching builtins.

• bpo-25688: Fixed file leak in ElementTree.iterparse() raising an error.

• bpo-23914: Fixed SystemError raised by unpickler on broken pickle data.

• bpo-25691: Fixed crash on deleting ElementTree.Element attributes.

• bpo-25624: ZipFile now always writes a ZIP_STORED header for directoryentries. Patch by Dingyuan Wang.

• bpo-25583: Avoid incorrect errors raised by os.makedirs(exist_ok=True)when the OS gives priority to errors such as EACCES over EEXIST.

• bpo-25593: Change semantics of EventLoop.stop() in asyncio.

• bpo-6973: When we know a subprocess.Popen process has died, do not allowthe send_signal(), terminate(), or kill() methods to do anything as theycould potentially signal a different process.

• bpo-25578: Fix (another) memory leak in SSLSocket.getpeercer().

• bpo-25590: In the Readline completer, only call getattr() once perattribute.

• bpo-25498: Fix a crash when garbage-collecting ctypes objects created bywrapping a memoryview. This was a regression made in 3.4.3. Based onpatch by Eryksun.

• bpo-18010: Fix the pydoc web server’s module search function to handleexceptions from importing packages.

• bpo-25510: fileinput.FileInput.readline() now returns b’’ instead of ‘’ atthe end if the FileInput was opened with binary mode. Patch by RyosukeIto.

• bpo-25530: Disable the vulnerable SSLv3 protocol by default when creatingssl.SSLContext.

• bpo-25569: Fix memory leak in SSLSocket.getpeercert().

• bpo-21827: Fixed textwrap.dedent() for the case when largest commonwhitespace is a substring of smallest leading whitespace. Based on patchby Robert Li.

• bpo-25471: Sockets returned from accept() shouldn’t appear to benonblocking.

• bpo-25441: asyncio: Raise error from drain() when socket is closed.

• bpo-25411: Improved Unicode support in SMTPHandler through better use ofthe email package. Thanks to user simon04 for the patch.

• bpo-25380: Fixed protocol for the STACK_GLOBAL opcode inpickletools.opcodes.

• bpo-23972: Updates asyncio datagram create method allowing reuseport andreuseaddr socket options to be set prior to binding the socket. Mirroringthe existing asyncio create_server method the reuseaddr option fordatagram sockets defaults to True if the O/S is ‘posix’ (except if theplatform is Cygwin). Patch by Chris Laws.

• bpo-25304: Add asyncio.run_coroutine_threadsafe(). This lets you submit acoroutine to a loop from another thread, returning aconcurrent.futures.Future. By Vincent Michel.

• bpo-25319: When threading.Event is reinitialized, the underlying conditionshould use a regular lock rather than a recursive lock.

• bpo-25232: Fix CGIRequestHandler to split the query from the URL at thefirst question mark (?) rather than the last. Patch from Xiang Zhang.

• bpo-24657: Prevent CGIRequestHandler from collapsing slashes in the querypart of the URL as if it were a path. Patch from Xiang Zhang.

• bpo-22958: Constructor and update method of weakref.WeakValueDictionarynow accept the self and the dict keyword arguments.

• bpo-22609: Constructor of collections.UserDict now accepts the selfkeyword argument.

• bpo-25262: Added support for BINBYTES8 opcode in Python implementation ofunpickler. Highest 32 bits of 64-bit size for BINUNICODE8 and BINBYTES8opcodes no longer silently ignored on 32-bit platforms in Cimplementation.

• bpo-25034: Fix string.Formatter problem with auto-numbering and nestedformat_specs. Patch by Anthon van der Neut.

• bpo-25233: Rewrite the guts of asyncio.Queue and asyncio.Semaphore to bemore understandable and correct.

• bpo-23600: Default implementation of tzinfo.fromutc() was returning wrongresults in some cases.

• bpo-25203: Failed readline.set_completer_delims() no longer left themodule in inconsistent state.

• Prevent overflow in _Unpickler_Read.

• bpo-25047: The XML encoding declaration written by Element Tree nowrespects the letter case given by the user. This restores the ability towrite encoding names in uppercase like “UTF-8”, which worked in Python 2.

• bpo-19143: platform module now reads Windows version from kernel32.dll toavoid compatibility shims.

• bpo-23517: Fix rounding in fromtimestamp() and utcfromtimestamp() methodsof datetime.datetime: microseconds are now rounded to nearest with tiesgoing to nearest even integer (ROUND_HALF_EVEN), instead of being roundingtowards zero (ROUND_DOWN). It’s important that these methods use the samerounding mode than datetime.timedelta to keep the property:(datetime(1970,1,1) + timedelta(seconds=t)) ==datetime.utcfromtimestamp(t). It also the rounding mode used byround(float) for example.

• bpo-24684: socket.socket.getaddrinfo() now callsPyUnicode_AsEncodedString() instead of calling the encode() method of thehost, to handle correctly custom string with an encode() method whichdoesn’t return a byte string. The encoder of the IDNA codec is now calleddirectly instead of calling the encode() method of the string.

• bpo-24982: shutil.make_archive() with the “zip” format now adds entriesfor directories (including empty directories) in ZIP file.

• bpo-24857: Comparing call_args to a long sequence now correctly returns aboolean result instead of raising an exception. Patch by A Kaptur.

• bpo-25019: Fixed a crash caused by setting non-string key of expat parser.Based on patch by John Leitch.

• bpo-24917: time_strftime() buffer over-read.

• bpo-23144: Make sure that HTMLParser.feed() returns all the data, evenwhen convert_charrefs is True.

• bpo-16180: Exit pdb if file has syntax error, instead of trapping user inan infinite loop. Patch by Xavier de Gaye.

• bpo-21112: Fix regression in unittest.expectedFailure on subclasses. Patchfrom Berker Peksag.

• bpo-24931: Instances of subclasses of namedtuples have their own __dict__which breaks the inherited __dict__ property and breaks the _asdict()method. Removed the __dict__ property to prevent the conflict and fixed_asdict().

• bpo-24764: cgi.FieldStorage.read_multi() now ignores the Content-Lengthheader in part headers. Patch written by Peter Landry and reviewed byPierre Quentel.

• bpo-24774: Fix docstring in http.server.test. Patch from Chiu-Hsiang Hsu.

• bpo-21159: Improve message inconfigparser.InterpolationMissingOptionError. Patch from Łukasz Langa.

• bpo-23888: Handle fractional time in cookie expiry. Patch by ssh.

• bpo-23004: mock_open() now reads binary data correctly when the type ofread_data is bytes. Initial patch by Aaron Hill.

• bpo-23652: Make it possible to compile the select module against the libcheaders from the Linux Standard Base, which do not include some EPOLLmacros. Patch by Matt Frank.

• bpo-22932: Fix timezones in email.utils.formatdate. Patch from DmitryShachnev.

• bpo-23779: imaplib raises TypeError if authenticator tries to abort. Patchfrom Craig Holmquist.

• bpo-23319: Fix ctypes.BigEndianStructure, swap correctly bytes. Patchwritten by Matthieu Gautier.

• bpo-23254: Document how to close the TCPServer listening socket. Patchfrom Martin Panter.

• bpo-19450: Update Windows and OS X installer builds to use SQLite 3.8.11.

• bpo-23441: rcompleter now prints a tab character instead of displayingpossible completions for an empty word. Initial patch by Martin Sekera.

• bpo-24735: Fix invalid memory access initertools.combinations_with_replacement().

• bpo-17527: Add PATCH to wsgiref.validator. Patch from Luca Sbardella.

• bpo-24683: Fixed crashes in _json functions called with arguments ofinappropriate type.

• bpo-21697: shutil.copytree() now correctly handles symbolic links thatpoint to directories. Patch by Eduardo Seabra and Thomas Kluyver.

• bpo-24620: Random.setstate() now validates the value of state lastelement.

• bpo-22153: Improve unittest docs. Patch from Martin Panter and evilzero.

• bpo-24206: Fixed __eq__ and __ne__ methods of inspect classes.

• bpo-21750: mock_open.read_data can now be read from each instance, as itcould in Python 3.3.

• bpo-23247: Fix a crash in the StreamWriter.reset() of CJK codecs.

• bpo-18622: unittest.mock.mock_open().reset_mock would recurse infinitely.Patch from Nicola Palumbo and Laurent De Buyst.

• bpo-24608: chunk.Chunk.read() now always returns bytes, not str.

• bpo-18684: Fixed reading out of the buffer in the re module.

• bpo-24259: tarfile now raises a ReadError if an archive is truncatedinside a data segment.

• bpo-24552: Fix use after free in an error case of the _pickle module.

• bpo-24514: tarfile now tolerates number fields consisting of onlywhitespace.

• bpo-19176: Fixed doctype() related bugs in C implementation ofElementTree. A deprecation warning no longer issued by XMLParser subclasswith default doctype() method. Direct call of doctype() now issues awarning. Parser’s doctype() now is not called if target’s doctype() iscalled. Based on patch by Martin Panter.

• bpo-20387: Restore semantic round-trip correctness in tokenize/untokenizefor tab- indented blocks.

• bpo-24456: Fixed possible buffer over-read in adpcm2lin() and lin2adpcm()functions of the audioop module.

• bpo-24336: The contextmanager decorator now works with functions withkeyword arguments called “func” and “self”. Patch by Martin Panter.

• bpo-24489: ensure a previously set C errno doesn’t disturb cmath.polar().

• bpo-5633: Fixed timeit when the statement is a string and the setup isnot.

• bpo-24326: Fixed audioop.ratecv() with non-default weightB argument.Original patch by David Moore.

• bpo-23840: tokenize.open() now closes the temporary binary file on errorto fix a resource warning.

• bpo-24257: Fixed segmentation fault in sqlite3.Row constructor with fakedcursor type.

• bpo-22107: tempfile.gettempdir() and tempfile.mkdtemp() now try again whena directory with the chosen name already exists on Windows as well as onUnix. tempfile.mkstemp() now fails early if parent directory is not valid(not exists or is a file) on Windows.

• bpo-6598: Increased time precision and random number range inemail.utils.make_msgid() to strengthen the uniqueness of the message ID.

• bpo-24091: Fixed various crashes in corner cases in C implementation ofElementTree.

• bpo-21931: msilib.FCICreate() now raises TypeError in the case of a badargument instead of a ValueError with a bogus FCI error number. Patch byJeffrey Armstrong.

• bpo-23796: peek and read1 methods of BufferedReader now raise ValueErrorif they called on a closed object. Patch by John Hergenroeder.

• bpo-24521: Fix possible integer overflows in the pickle module.

• bpo-22931: Allow ‘[‘ and ‘]’ in cookie values.

• bpo-20274: Remove ignored and erroneous “kwargs” parameters from threeMETH_VARARGS methods on _sqlite.Connection.

• bpo-24094: Fix possible crash in json.encode with poorly behaved dictsubclasses.

• Asyncio issue 222 / PR 231 (Victor Stinner) – fix @coroutine functionswithout __name__.

• bpo-9246: On POSIX, os.getcwd() now supports paths longer than 1025 bytes.Patch written by William Orr.

• The keywords attribute of functools.partial is now always a dictionary.

• bpo-24099: Fix free-after-use bug in heapq’s siftup and siftdownfunctions. (See also: bpo-24100, bpo-24101)

• Backport collections.deque fixes from Python 3.5. Prevents reentrantbadness during deletion by deferring the decref until the container hasbeen restored to a consistent state.

• bpo-23008: Fixed resolving attributes with boolean value is False inpydoc.

• Fix asyncio issue 235: LifoQueue and PriorityQueue’s put didn’t incrementunfinished tasks (this bug was introduced in 3.4.3 when JoinableQueue wasmerged with Queue).

• bpo-23908: os functions now reject paths with embedded null character onWindows instead of silently truncate them.

• bpo-23728: binascii.crc_hqx() could return an integer outside of the range0-0xffff for empty data.

• bpo-23811: Add missing newline to the PyCompileError error message. Patchby Alex Shkop.

• bpo-17898: Fix exception in gettext.py when parsing certain plural forms.

• bpo-22982: Improve BOM handling when seeking to multiple positions of awritable text file.

• bpo-23865: close() methods in multiple modules now are idempotent and morerobust at shutdown. If they need to release multiple resources, all arereleased even if errors occur.

• bpo-23881: urllib.request.ftpwrapper constructor now closes the socket ifthe FTP connection failed to fix a ResourceWarning.

• bpo-23400: Raise same exception on both Python 2 and 3 if sem_open is notavailable. Patch by Davin Potts.

• bpo-15133: _tkinter.tkapp.getboolean() now supports Tcl_Obj and alwaysreturns bool. tkinter.BooleanVar now validates input values (acceptedbool, int, str, and Tcl_Obj). tkinter.BooleanVar.get() now always returnsbool.

• bpo-23338: Fixed formatting ctypes error messages on Cygwin. Patch byMakoto Kato.

• bpo-16840: Tkinter now supports 64-bit integers added in Tcl 8.4 andarbitrary precision integers added in Tcl 8.5.

• bpo-23834: Fix socket.sendto(), use the C Py_ssize_t type to store theresult of sendto() instead of the C int type.

• bpo-21526: Tkinter now supports new boolean type in Tcl 8.5.

• bpo-23838: linecache now clears the cache and returns an empty result onMemoryError.

• bpo-18473: Fixed 2to3 and 3to2 compatible pickle mappings. Fixedambigious reverse mappings. Added many new mappings. Import mapping isno longer applied to modules already mapped with full name mapping.

• bpo-23745: The new email header parser now handles duplicate MIMEparameter names without error, similar to how get_param behaves.

• bpo-23792: Ignore KeyboardInterrupt when the pydoc pager is active. Thismimics the behavior of the standard unix pagers, and prevents pipepagerfrom shutting down while the pager itself is still running.

• bpo-23742: ntpath.expandvars() no longer loses unbalanced single quotes.

• bpo-21802: The reader in BufferedRWPair now is closed even when closingwriter failed in BufferedRWPair.close().

• bpo-23671: string.Template now allows to specify the “self” parameter askeyword argument. string.Formatter now allows to specify the “self” andthe “format_string” parameters as keyword arguments.

• bpo-21560: An attempt to write a data of wrong type no longer causeGzipFile corruption. Original patch by Wolfgang Maier.

• bpo-23647: Increase impalib’s MAXLINE to accommodate modern mailbox sizes.

• bpo-23539: If body is None, http.client.HTTPConnection.request now setsContent-Length to 0 for PUT, POST, and PATCH headers to avoid 411 errorsfrom some web servers.

• bpo-22351: The nntplib.NNTP constructor no longer leaves the connectionand socket open until the garbage collector cleans them up. Patch byMartin Panter.

• bpo-23136: _strptime now uniformly handles all days in week 0, includingDec 30 of previous year. Based on patch by Jim Carroll.

• bpo-23700: Iterator of NamedTemporaryFile now keeps a reference toNamedTemporaryFile instance. Patch by Bohuslav Kabrda.

• bpo-22903: The fake test case created by unittest.loader when it failsimporting a test module is now picklable.

• bpo-23568: Add rdivmod support to MagicMock() objects. Patch by HåkanLövdahl.

• bpo-23138: Fixed parsing cookies with absent keys or values in cookiejar.Patch by Demian Brecht.

• bpo-23051: multiprocessing.Pool methods imap() and imap_unordered() nowhandle exceptions raised by an iterator. Patch by Alon Diamant and DavinPotts.

• bpo-22928: Disabled HTTP header injections in http.client. Original patchby Demian Brecht.

• bpo-23615: Modules bz2, tarfile and tokenize now can be reloaded withimp.reload(). Patch by Thomas Kluyver.

• bpo-23476: In the ssl module, enable OpenSSL’s X509_V_FLAG_TRUSTED_FIRSTflag on certificate stores when it is available.

• bpo-23576: Avoid stalling in SSL reads when EOF has been reached in theSSL layer but the underlying connection hasn’t been closed.

• bpo-23504: Added an __all__ to the types module.

• bpo-20204: Added the __module__ attribute to _tkinter classes.

• bpo-23521: Corrected pure python implementation of timedelta division.

  Eliminated OverflowError from timedelta * float for some floats; Correctedrounding in timedlta true division.

• bpo-21619: Popen objects no longer leave a zombie after exit in the withstatement if the pipe was broken. Patch by Martin Panter.

• bpo-6639: Module-level turtle functions no longer raise TclError afterclosing the window.

• bpo-814253: Warnings now are raised when group references and conditionalgroup references are used in lookbehind assertions in regular expressions.(See also: bpo-9179)

• bpo-23215: Multibyte codecs with custom error handlers that ignores errorsconsumed too much memory and raised SystemError or MemoryError. Originalpatch by Aleksi Torhamo.

• bpo-5700: io.FileIO() called flush() after closing the file. flush() wasnot called in close() if closefd=False.

• bpo-23374: Fixed pydoc failure with non-ASCII files when stdout encodingdiffers from file system encoding (e.g. on Mac OS).

• bpo-23481: Remove RC4 from the SSL module’s default cipher list.

• bpo-21548: Fix pydoc.synopsis() and pydoc.apropos() on modules with emptydocstrings.

• bpo-22885: Fixed arbitrary code execution vulnerability in the dbm.dumbmodule. Original patch by Claudiu Popa.

• bpo-23146: Fix mishandling of absolute Windows paths with forward slashesin pathlib.

• bpo-23421: Fixed compression in tarfile CLI. Patch by wdv4758h.

• bpo-23367: Fix possible overflows in the unicodedata module.

• bpo-23361: Fix possible overflow in Windows subprocess creation code.

• bpo-23801: Fix issue where cgi.FieldStorage did not always ignore theentire preamble to a multipart body.

• bpo-23310: Fix MagicMock’s initializer to work with __methods__, just likeconfigure_mock(). Patch by Kasia Jachim.

• asyncio: New event loop APIs: set_task_factory() and get_task_factory().

• asyncio: async() function is deprecated in favour of ensure_future().

• bpo-23898: Fix inspect.classify_class_attrs() to support attributes withoverloaded __eq__ and __bool__. Patch by Mike Bayer.

• bpo-24298: Fix inspect.signature() to correctly unwrap wrappers aroundbound methods.

• bpo-23572: Fixed functools.singledispatch on classes with falsymetaclasses. Patch by Ethan Furman.

IDLE¶

• bpo-15348: Stop the debugger engine (normally in a user process) beforeclosing the debugger window (running in the IDLE process). This preventsthe RuntimeErrors that were being caught and ignored.
• bpo-24455: Prevent IDLE from hanging when a) closing the shell while thedebugger is active (15347); b) closing the debugger with the [X] button(15348); and c) activating the debugger when already active (24455). Thepatch by Mark Roseman does this by making two changes. 1. Suspend andresume the gui.interaction method with the tcl vwait mechanism intendedfor this purpose (instead of root.mainloop & .quit). 2. In gui.run, allowany existing interaction to terminate first.
• Change ‘The program’ to ‘Your program’ in an IDLE ‘kill program?’ messageto make it clearer that the program referred to is the currently runninguser program, not IDLE itself.
• bpo-24750: Improve the appearance of the IDLE editor window status bar.Patch by Mark Roseman.
• bpo-25313: Change the handling of new built-in text color themes to betteraddress the compatibility problem introduced by the addition of IDLE Dark.Consistently use the revised idleConf.CurrentTheme everywhere in idlelib.
• bpo-24782: Extension configuration is now a tab in the IDLE Preferencesdialog rather than a separate dialog. The former tabs are now a sortedlist. Patch by Mark Roseman.
• bpo-22726: Re-activate the config dialog help button with some contentabout the other buttons and the new IDLE Dark theme.
• bpo-24820: IDLE now has an ‘IDLE Dark’ built-in text color theme. It ismore or less IDLE Classic inverted, with a cobalt blue background.Strings, comments, keywords, ... are still green, red, orange, ... . Touse it with IDLEs released before November 2015, hit the ‘Save as NewCustom Theme’ button and enter a new name, such as ‘Custom Dark’. Thecustom theme will work with any IDLE release, and can be modified.
• bpo-25224: README.txt is now an idlelib index for IDLE developers andcurious users. The previous user content is now in the IDLE doc chapter.‘IDLE’ now means ‘Integrated Development and Learning Environment’.
• bpo-24820: Users can now set breakpoint colors in Settings -> CustomHighlighting. Original patch by Mark Roseman.
• bpo-24972: Inactive selection background now matches active selectionbackground, as configured by users, on all systems. Found items are nowalways highlighted on Windows. Initial patch by Mark Roseman.
• bpo-24570: Idle: make calltip and completion boxes appear on Macs affectedby a tk regression. Initial patch by Mark Roseman.
• bpo-24988: Idle ScrolledList context menus (used in debugger) now work onMac Aqua. Patch by Mark Roseman.
• bpo-24801: Make right-click for context menu work on Mac Aqua. Patch byMark Roseman.
• bpo-25173: Associate tkinter messageboxes with a specific widget. For MacOSX, make them a ‘sheet’. Patch by Mark Roseman.
• bpo-25198: Enhance the initial html viewer now used for Idle Help. *Properly indent fixed-pitch text (patch by Mark Roseman). * Give codesnippet a very Sphinx- like light blueish-gray background. * Re-useinitial width and height set by users for shell and editor. * When theTable of Contents (TOC) menu is used, put the section header at the top ofthe screen.
• bpo-25225: Condense and rewrite Idle doc section on text colors.
• bpo-21995: Explain some differences between IDLE and console Python.
• bpo-22820: Explain need forprint when running file from Idle editor.
• bpo-25224: Doc: augment Idle feature list and no-subprocess section.
• bpo-25219: Update doc for Idle command line options. Some were missing andnotes were not correct.
• bpo-24861: Most of idlelib is private and subject to change. Useidleib.idle.* to start Idle. See idlelib.__init__.__doc__.
• bpo-25199: Idle: add synchronization comments for future maintainers.
• bpo-16893: Replace help.txt with help.html for Idle doc display. The newidlelib/help.html is rstripped Doc/build/html/library/idle.html. It looksbetter than help.txt and will better document Idle as released. Thetkinter html viewer that works for this file was written by Mark Roseman.The now unused EditorWindow.HelpDialog class and helt.txt file aredeprecated.
• bpo-24199: Deprecate unused idlelib.idlever with possible removal in 3.6.
• bpo-24790: Remove extraneous code (which also create 2 & 3 conflicts).
• bpo-23672: Allow Idle to edit and run files with astral chars in name.Patch by Mohd Sanad Zaki Rizvi.
• bpo-24745: Idle editor default font. Switch from Courier toplatform-sensitive TkFixedFont. This should not affect current customizedfont selections. If there is a problem, edit$HOME/.idlerc/config-main.cfg and remove ‘fontxxx’ entries from [EditorWindow]. Patch by Mark Roseman.
• bpo-21192: Idle editor. When a file is run, put its name in the restartbar. Do not print false prompts. Original patch by Adnan Umer.
• bpo-13884: Idle menus. Remove tearoff lines. Patch by Roger Serwy.
• bpo-23184: remove unused names and imports in idlelib. Initial patch by AlSweigart.

Tests¶

• bpo-25616: Tests for OrderedDict are extracted from test_collections intoseparate file test_ordered_dict.
• bpo-25099: Make test_compileall not fail when an entry on sys.path cannotbe written to (commonly seen in administrative installs on Windows).
• bpo-24751: When running regrtest with the-w command line option, atest run is no longer marked as a failure if all tests succeed whenre-run.
• bpo-21520: test_zipfile no longer fails if the word ‘bad’ appears anywherein the name of the current directory.
• bpo-23799: Added test.support.start_threads() for running and cleaning upmultiple threads.
• bpo-22390: test.regrtest now emits a warning if temporary files ordirectories are left after running a test.
• bpo-23583: Added tests for standard IO streams in IDLE.

Build¶

• bpo-23445: pydebug builds now use “gcc -Og” where possible, to make theresulting executable faster.
• bpo-24603: Update Windows builds to use OpenSSL1.0.2d and OS X 10.5installer to use OpenSSL 1.0.2e.

C API¶

• bpo-23998: PyImport_ReInitLock() now checks for lock allocation error

Documentation¶

• bpo-12067: Rewrite Comparisons section in the Expressions chapter of thelanguage reference. Some of the details of comparing mixed types wereincorrect or ambiguous. NotImplemented is only relevant at a lower levelthan the Expressions chapter. Added details of comparing range() objects,and default behaviour and consistency suggestions for user-definedclasses. Patch from Andy Maier.
• bpo-24952: Clarify the default size argument of stack_size() in the“threading” and “_thread” modules. Patch from Mattip.
• bpo-24808: Update the types of some PyTypeObject fields. Patch by JosephWeston.
• bpo-22812: Fix unittest discovery examples. Patch from Pam McA’Nulty.
• bpo-24129: Clarify the reference documentation for name resolution. Thisincludes removing the assumption that readers will be familiar with thename resolution scheme Python used prior to the introduction of lexicalscoping for function namespaces. Patch by Ivan Levkivskyi.
• bpo-20769: Improve reload() docs. Patch by Dorian Pula.
• bpo-23589: Remove duplicate sentence from the FAQ. Patch by Yongzhi Pan.
• bpo-24729: Correct IO tutorial to match implementation regarding encodingparameter to open function.
• bpo-24351: Clarify what is meant by “identifier” in the context ofstring.Template instances.
• bpo-22155: Add File Handlers subsection with createfilehandler to tkinterdoc. Remove obsolete example from FAQ. Patch by Martin Panter.
• bpo-24029: Document the name binding behavior for submodule imports.
• bpo-24077: Fix typo in man page for -I command option: -s, not -S.

Tools/Demos¶

• bpo-25440: Fix output of python-config –extension-suffix.
• bpo-23330: h2py now supports arbitrary filenames in #include.
• bpo-24031: make patchcheck now supports git checkouts, too.

Windows¶

• bpo-24306: Sets component ID for launcher to match 3.5 and later to avoiddowngrading.
• bpo-25022: Removed very outdated PC/example_nt/ directory.

Core and Builtins¶

• bpo-22735: Fix many edge cases (including crashes) involving custom mro()implementations.
• bpo-22896: Avoid using PyObject_AsCharBuffer(), PyObject_AsReadBuffer()and PyObject_AsWriteBuffer().
• bpo-21295: Revert some changes (issue #16795) to AST line numbers andcolumn offsets that constituted a regression.
• bpo-21408: The default __ne__() now returns NotImplemented if __eq__()returned NotImplemented. Original patch by Martin Panter.
• bpo-23321: Fixed a crash in str.decode() when error handler returnedreplacment string longer than mailformed input data.
• bpo-23048: Fix jumping out of an infinite while loop in the pdb.
• bpo-20335: bytes constructor now raises TypeError when encoding or errorsis specified with non-string argument. Based on patch by Renaud Blanch.
• bpo-22335: Fix crash when trying to enlarge a bytearray to 0x7fffffffbytes on a 32-bit platform.
• bpo-22653: Fix an assertion failure in debug mode when doing a reentrantdict insertion in debug mode.
• bpo-22643: Fix integer overflow in Unicode case operations (upper, lower,title, swapcase, casefold).
• bpo-22604: Fix assertion error in debug mode when dividing a complexnumber by (nan+0j).
• bpo-22470: Fixed integer overflow issues in “backslashreplace”,“xmlcharrefreplace”, and “surrogatepass” error handlers.
• bpo-22520: Fix overflow checking when generating the repr of a unicodeobject.
• bpo-22519: Fix overflow checking in PyBytes_Repr.
• bpo-22518: Fix integer overflow issues in latin-1 encoding.
• bpo-23165: Perform overflow checks before allocating memory in the_Py_char2wchar function.

Library¶

• bpo-23399: pyvenv creates relative symlinks where possible.
• bpo-23099: Closing io.BytesIO with exported buffer is rejected now toprevent corrupting exported buffer.
• bpo-23363: Fix possible overflow in itertools.permutations.
• bpo-23364: Fix possible overflow in itertools.product.
• bpo-23366: Fixed possible integer overflow in itertools.combinations.
• bpo-23369: Fixed possible integer overflow in_json.encode_basestring_ascii.
• bpo-23353: Fix the exception handling of generators inPyEval_EvalFrameEx(). At entry, save or swap the exception state even ifPyEval_EvalFrameEx() is called with throwflag=0. At exit, the exceptionstate is now always restored or swapped, not only if why is WHY_YIELD orWHY_RETURN. Patch co-written with Antoine Pitrou.
• bpo-18518: timeit now rejects statements which can’t be compiled outside afunction or a loop (e.g. “return” or “break”).
• bpo-23094: Fixed readline with frames in Python implementation of pickle.
• bpo-23268: Fixed bugs in the comparison of ipaddress classes.
• bpo-21408: Removed incorrect implementations of __ne__() which didn’treturned NotImplemented if __eq__() returned NotImplemented. The default__ne__() now works correctly.
• bpo-19996:email.feedparser.FeedParser now handles (malformed)headers with no key rather than assuming the body has started.
• bpo-23248: Update ssl error codes from latest OpenSSL git master.
• bpo-23098: 64-bit dev_t is now supported in the os module.
• bpo-23250: In the http.cookies module, capitalize “HttpOnly” and “Secure”as they are written in the standard.
• bpo-23063: In the disutils’ check command, fix parsing of reST with codeor code-block directives.
• bpo-23209: selectors.BaseSelector.close() now clears its internalreference to the selector mapping to break a reference cycle. Initialpatch written by Martin Richard. (See also: bpo-23225)
• bpo-21356: Make ssl.RAND_egd() optional to support LibreSSL. Theavailability of the function is checked during the compilation. Patchwritten by Bernard Spil.
• bpo-20896: Thessl.get_server_certificate() function now uses thePROTOCOL_SSLv23 protocol by default, notPROTOCOL_SSLv3, for maximum compatibility and supportplatforms wherePROTOCOL_SSLv3 support is disabled. (Seealso: bpo-22935)
• bpo-23111: In the ftplib, make ssl.PROTOCOL_SSLv23 the default protocolversion.
• bpo-23132: Mitigate regression in speed and clarity infunctools.total_ordering.
• bpo-22585: On OpenBSD 5.6 and newer, os.urandom() now calls getentropy(),instead of reading /dev/urandom, to get pseudo-random bytes.
• bpo-23112: Fix SimpleHTTPServer to correctly carry the query string andfragment when it redirects to add a trailing slash.
• bpo-23093: In the io, module allow more operations to work on detachedstreams.
• bpo-19104: pprint now produces evaluable output for wrapped strings.
• bpo-23071: Added missing names to codecs.__all__. Patch by Martin Panter.
• bpo-15513: Added a __sizeof__ implementation for pickle classes.
• bpo-19858: pickletools.optimize() now aware of the MEMOIZE opcode, canproduce more compact result and no longer produces invalid output if inputdata contains MEMOIZE opcodes together with PUT or BINPUT opcodes.
• bpo-22095: Fixed HTTPConnection.set_tunnel with default port. The portvalue in the host header was set to “None”. Patch by Demian Brecht.
• bpo-23016: A warning no longer produces an AttributeError when the programis run with pythonw.exe.
• bpo-21775: shutil.copytree(): fix crash when copying to VFAT. An exceptionhandler assumed that that OSError objects always have a ‘winerror’attribute. That is not the case, so the exception handler itself raisedAttributeError when run on Linux (and, presumably, any other non-WindowsOS). Patch by Greg Ward.
• bpo-1218234: Fix inspect.getsource() to load updated source of reloadedmodule. Initial patch by Berker Peksag.
• bpo-22959: In the constructor of http.client.HTTPSConnection, prefer thecontext’s check_hostname attribute over thecheck_hostname parameter.
• bpo-16043: Add a default limit for the amount of dataxmlrpclib.gzip_decode will return. This resolves CVE-2013-1753.
• bpo-22966: Fix __pycache__ pyc file name clobber when pyc_compile is askedto compile a source file containing multiple dots in the source file name.
• bpo-21971: Update turtledemo doc and add module to the index.
• bpo-21032: Fixed socket leak if HTTPConnection.getresponse() fails.Original patch by Martin Panter.
• bpo-22960: Add a context argument to xmlrpclib.ServerProxy constructor.
• bpo-22915: SAX parser now supports files opened with file descriptor orbytes path.
• bpo-22609: Constructors and update methods of mapping classes in thecollections module now accept the self keyword argument.
• bpo-22788: Addcontext parameter to logging.handlers.HTTPHandler.
• bpo-22921: Allow SSLContext to take thehostname parameter even ifOpenSSL doesn’t support SNI.
• bpo-22894: TestCase.subTest() would cause the test suite to be stoppedwhen in failfast mode, even in the absence of failures.
• bpo-22638: SSLv3 is now disabled throughout the standard library. It canstill be enabled by instantiating a SSLContext manually.
• bpo-22370: Windows detection in pathlib is now more robust.
• bpo-22841: Reject coroutines in asyncio add_signal_handler(). Patch byLudovic.Gasc.
• bpo-22849: Fix possible double free in the io.TextIOWrapper constructor.
• bpo-12728: Different Unicode characters having the same uppercase butdifferent lowercase are now matched in case-insensitive regularexpressions.
• bpo-22821: Fixed fcntl() with integer argument on 64-bit big-endianplatforms.
• bpo-22406: Fixed the uu_codec codec incorrectly ported to 3.x. Based onpatch by Martin Panter.
• bpo-17293: uuid.getnode() now determines MAC address on AIX using netstat.Based on patch by Aivars Kalvāns.
• bpo-22769: Fixed ttk.Treeview.tag_has() when called without arguments.
• bpo-22417: Verify certificates by default in httplib (PEP 476).
• bpo-22775: Fixed unpickling of http.cookies.SimpleCookie with protocol 2and above. Patch by Tim Graham.
• bpo-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.
• bpo-22776: Brought excluded code into the scope of a try block inSysLogHandler.emit().
• bpo-22665: Add missing get_terminal_size and SameFileError toshutil.__all__.
• bpo-17381: Fixed handling of case-insensitive ranges in regularexpressions.
• bpo-22410: Module level functions in the re module now cache compiledlocale-dependent regular expressions taking into account the locale.
• bpo-22759: Query methods on pathlib.Path() (exists(), is_dir(), etc.) nowreturn False when the underlying stat call raises NotADirectoryError.
• bpo-8876: distutils now falls back to copying files when hard linkingdoesn’t work. This allows use with special filesystems such as VirtualBoxshared folders.
• bpo-18853: Fixed ResourceWarning in shlex.__nain__.
• bpo-9351: Defaults set with set_defaults on an argparse subparser are nolonger ignored when also set on the parent parser.
• bpo-21991: Make email.headerregistry’s header ‘params’ attributes beread-only (MappingProxyType). Previously the dictionary was modifiablebut a new one was created on each access of the attribute.
• bpo-22641: In asyncio, the default SSL context for client connections isnow created using ssl.create_default_context(), for stronger security.
• bpo-22435: Fix a file descriptor leak when SocketServer bind fails.
• bpo-13096: Fixed segfault in CTypes POINTER handling of large values.
• bpo-11694: Raise ConversionError in xdrlib as documented. Patch by FilipGruszczyński and Claudiu Popa.
• bpo-22462: Fix pyexpat’s creation of a dummy frame to make it appear inexception tracebacks.
• bpo-21173: Fix len() on a WeakKeyDictionary when .clear() was called withan iterator alive.
• bpo-11866: Eliminated race condition in the computation of names for newthreads.
• bpo-21905: Avoid RuntimeError in pickle.whichmodule() when sys.modules ismutated while iterating. Patch by Olivier Grisel.
• bpo-22219: The zipfile module CLI now adds entries for directories(including empty directories) in ZIP file.
• bpo-22449: In the ssl.SSLContext.load_default_certs, consult theenvironmental variables SSL_CERT_DIR and SSL_CERT_FILE on Windows.
• bpo-20076: Added non derived UTF-8 aliases to locale aliases table.
• bpo-20079: Added locales supported in glibc 2.18 to locale alias table.
• bpo-22396: On 32-bit AIX platform, don’t expose os.posix_fadvise() noros.posix_fallocate() because their prototypes in system headers are wrong.
• bpo-22517: When a io.BufferedRWPair object is deallocated, clear itsweakrefs.
• bpo-22448: Improve canceled timer handles cleanup to prevent unboundmemory usage. Patch by Joshua Moore-Oliva.
• bpo-23009: Make sure selectors.EpollSelecrtor.select() works when no FD isregistered.

IDLE¶

• bpo-20577: Configuration of the max line length for the FormatParagraphextension has been moved from the General tab of the Idle preferencesdialog to the FormatParagraph tab of the Config Extensions dialog. Patchby Tal Einat.
• bpo-16893: Update Idle doc chapter to match current Idle and add newinformation.
• bpo-3068: Add Idle extension configuration dialog to Options menu. Changesare written to HOME/.idlerc/config-extensions.cfg. Original patch by TalEinat.
• bpo-16233: A module browser (File : Class Browser, Alt+C) requires aneditor window with a filename. When Class Browser is requested otherwise,from a shell, output window, or ‘Untitled’ editor, Idle no longer displaysan error box. It now pops up an Open Module box (Alt+M). If a valid nameis entered and a module is opened, a corresponding browser is also opened.
• bpo-4832: Save As to type Python files automatically adds .py to the nameyou enter (even if your system does not display it). Some systemsautomatically add .txt when type is Text files.
• bpo-21986: Code objects are not normally pickled by the pickle module. Tomatch this, they are no longer pickled when running under Idle.
• bpo-23180: Rename IDLE “Windows” menu item to “Window”. Patch by AlSweigart.

Tests¶

• bpo-23392: Added tests for marshal C API that works with FILE*.
• bpo-18982: Add tests for CLI of the calendar module.
• bpo-19548: Added some additional checks to test_codecs to ensure thatstatements in the updated documentation remain accurate. Patch by MartinPanter.
• bpo-22838: All test_re tests now work with unittest test discovery.
• bpo-22173: Update lib2to3 tests to use unittest test discovery.
• bpo-16000: Convert test_curses to use unittest.
• bpo-21456: Skip two tests in test_urllib2net.py if _ssl module notpresent. Patch by Remi Pointel.
• bpo-22770: Prevent some Tk segfaults on OS X when running gui tests.
• bpo-23211: Workaround test_logging failure on some OS X 10.6 systems.
• bpo-23345: Prevent test_ssl failures with large OpenSSL patch level values(like 0.9.8zc).
• bpo-22289: Prevent test_urllib2net failures due to ftp connection timeout.

Build¶

• bpo-15506: Use standard PKG_PROG_PKG_CONFIG autoconf macro in theconfigure script.
• bpo-22935: Allow the ssl module to be compiled if openssl doesn’t supportSSL 3.
• bpo-16537: Check whether self.extensions is empty in setup.py. Patch byJonathan Hosmer.
• bpo-18096: Fix library order returned by python-config.
• bpo-17219: Add library build dir for Python extension cross-builds.
• bpo-17128: Use private version of OpenSSL for 3.4.3 OS X 10.5+ installer.

C API¶

• bpo-22079: PyType_Ready() now checks that statically allocated type has nodynamically allocated bases.

Documentation¶

• bpo-19548: Update the codecs module documentation to better cover thedistinction between text encodings and other codecs, together with otherclarifications. Patch by Martin Panter.
• bpo-22914: Update the Python 2/3 porting HOWTO to describe a moreautomated approach.
• bpo-21514: The documentation of the json module now refers to new JSON RFC7159 instead of obsoleted RFC 4627.

Tools/Demos¶

• bpo-22314: pydoc now works when the LINES environment variable is set.

Windows¶

• bpo-17896: The Windows build scripts now expect external library sourcesto be inPCbuild\..\externals rather thanPCbuild\..\...
• bpo-17717: The Windows build scripts now use a copy of NASM pulled fromsvn.python.org to build OpenSSL.
• bpo-22644: The bundled version of OpenSSL has been updated to 1.0.1j.

Library¶

• bpo-10510: distutils register and upload methods now use HTML standardscompliant CRLF line endings.
• bpo-9850: Fixed macpath.join() for empty first component. Patch by OlegOshmyan.
• bpo-22427: TemporaryDirectory no longer attempts to clean up twice whenused in the with statement in generator.
• bpo-20912: Now directories added to ZIP file have correct Unix and MS-DOSdirectory attributes.
• bpo-21866: ZipFile.close() no longer writes ZIP64 central directoryrecords if allowZip64 is false.
• bpo-22415: Fixed debugging output of the GROUPREF_EXISTS opcode in the remodule. Removed trailing spaces in debugging output.
• bpo-22423: Unhandled exception in thread no longer causes unhandledAttributeError when sys.stderr is None.
• bpo-21332: Ensure thatbufsize=1 in subprocess.Popen() selects linebuffering, rather than block buffering. Patch by Akira Li.

Core and Builtins¶

• bpo-22258: Fix the the internal function set_inheritable() on Illumos.This platform exposes the functionioctl(FIOCLEX), but calling itfails with errno is ENOTTY: “Inappropriate ioctl for device”.set_inheritable() now falls back to the slowerfcntl() (F_GETFDand thenF_SETFD).
• bpo-21669: With the aid of heuristics in SyntaxError.__init__, the parsernow attempts to generate more meaningful (or at least more search enginefriendly) error messages when “exec” and “print” are used as statements.
• bpo-21642: In the conditional if-else expression, allow an integer writtenwith no space between itself and theelse keyword (e.g.Trueif42elseFalse) to be valid syntax.
• bpo-21523: Fix over-pessimistic computation of the stack effect of someopcodes in the compiler. This also fixes a quadratic compilation timeissue noticeable when compiling code with a large number of “and” and “or”operators.

Library¶

• bpo-21091: Fix API bug: email.message.EmailMessage.is_attachment is now amethod. Since EmailMessage is provisional, we can change the API in amaintenance release, but we use a trick to remain backward compatible with3.4.0/1.
• bpo-21079: Fix email.message.EmailMessage.is_attachment to return thecorrect result when the header has parameters as well as a value.
• bpo-22247: Add NNTPError to nntplib.__all__.
• bpo-4180: The warnings registries are now reset when the filters aremodified.
• bpo-22419: Limit the length of incoming HTTP request in wsgiref server to65536 bytes and send a 414 error code for higher lengths. Patchcontributed by Devin Cook.
• Lax cookie parsing in http.cookies could be a security issue when combinedwith non-standard cookie handling in some Web browsers. Reported bySergey Bobrov.
• bpo-22384: An exception in Tkinter callback no longer crashes the programwhen it is run with pythonw.exe.
• bpo-22168: Prevent turtle AttributeError with non-default Canvas on OS X.
• bpo-21147: sqlite3 now raises an exception if the request contains a nullcharacter instead of truncate it. Based on patch by Victor Stinner.
• bpo-21951: Fixed a crash in Tkinter on AIX when called Tcl command withempty string or tuple argument.
• bpo-21951: Tkinter now most likely raises MemoryError instead of crash ifthe memory allocation fails.
• bpo-22338: Fix a crash in the json module on memory allocation failure.
• bpo-22226: First letter no longer is stripped from the “status” key in theresult of Treeview.heading().
• bpo-19524: Fixed resource leak in the HTTP connection when an invalidresponse is received. Patch by Martin Panter.
• bpo-22051: turtledemo no longer reloads examples to re-run them.Initialization of variables and gui setup should be done in main(), whichis called each time a demo is run, but not on import.
• bpo-21933: Turtledemo users can change the code font size with a menuselection or control(command) ‘-‘ or ‘+’ or control-mousewheel. Originalpatch by Lita Cho.
• bpo-21597: The separator between the turtledemo text pane and the drawingcanvas can now be grabbed and dragged with a mouse. The code text panecan be widened to easily view or copy the full width of the text. Thecanvas can be widened on small screens. Original patches by Jan Kanis andLita Cho.
• bpo-18132: Turtledemo buttons no longer disappear when the window isshrunk. Original patches by Jan Kanis and Lita Cho.
• bpo-22216: smtplib now resets its state more completely after a quit. Themost obvious consequence of the previous behavior was a STARTTLS failureduring a connect/starttls/quit/connect/starttls sequence.
• bpo-22185: Fix an occasional RuntimeError in threading.Condition.wait()caused by mutation of the waiters queue without holding the lock. Patchby Doug Zongker.
• bpo-22182: Use e.args to unpack exceptions correctly indistutils.file_util.move_file. Patch by Claudiu Popa.
• The webbrowser module now uses subprocess’s start_new_session=True ratherthan a potentially risky preexec_fn=os.setsid call.
• bpo-22236: Fixed Tkinter images copying operations in NoDefaultRoot mode.
• bpo-22191: Fix warnings.__all__.
• bpo-15696: Add a __sizeof__ implementation for mmap objects on Windows.
• bpo-22068: Avoided reference loops with Variables and Fonts in Tkinter.
• bpo-22165: SimpleHTTPRequestHandler now supports undecodable file names.
• bpo-8797: Raise HTTPError on failed Basic Authentication immediately.Initial patch by Sam Bull.
• bpo-20729: Restored the use of lazy iterkeys()/itervalues()/iteritems() inthe mailbox module.
• bpo-21448: Changed FeedParser feed() to avoid O(N**2) behavior whenparsing long line. Original patch by Raymond Hettinger.
• bpo-22184: The functools LRU Cache decorator factory now gives an earlierand clearer error message when the user forgets the required parameters.
• bpo-17923: glob() patterns ending with a slash no longer match non-dirs onAIX. Based on patch by Delhallt.
• bpo-21121: Don’t force 3rd party C extensions to be built with-Werror=declaration- after-statement.
• bpo-21975: Fixed crash when using uninitialized sqlite3.Row (in particularwhen unpickling pickled sqlite3.Row). sqlite3.Row is now initialized inthe __new__() method.
• bpo-21580: Now Tkinter correctly handles bytes arguments passed to Tk. Inparticular this allows to initialize images from binary data.
• bpo-17172: Make turtledemo start as active on OS X even when run withsubprocess. Patch by Lita Cho.
• bpo-21704: Fix build error for _multiprocessing when semaphores are notavailable. Patch by Arfrever Frehtes Taifersar Arahesis.
• Fix repr(_socket.socket) on Windows 64-bit: don’t fail with OverflowErroron closed socket. repr(socket.socket) already works fine.
• bpo-16133: The asynchat.async_chat.handle_read() method now ignoresBlockingIOError exceptions.
• bpo-22044: Fixed premature DECREF in call_tzinfo_method. Patch by TomFlanagan.
• bpo-19884: readline: Disable the meta modifier key if stdout is not aterminal to not write the ANSI sequence “033[1034h” into stdout. Thissequence is used on some terminal (ex: TERM=xterm-256color”) to enablesupport of 8 bit characters.
• bpo-21888: plistlib’s load() and loads() now work if the fmt parameter isspecified.
• bpo-21044: tarfile.open() now handles fileobj with an integer ‘name’attribute. Based on patch by Antoine Pietri.
• bpo-21867: Prevent turtle crash due to invalid undo buffer size.
• bpo-19076: Don’t pass the redundant ‘file’ argument to self.error().
• bpo-21942: Fixed source file viewing in pydoc’s server mode on Windows.
• bpo-11259: asynchat.async_chat().set_terminator() now raises a ValueErrorif the number of received bytes is negative.
• bpo-12523: asynchat.async_chat.push() now raises a TypeError if it doesn’tget a bytes string
• bpo-21707: Add missing kwonlyargcount argument toModuleFinder.replace_paths_in_code().
• bpo-20639: calling Path.with_suffix(‘’) allows removing the suffix again.Patch by July Tikhonov.
• bpo-21714: Disallow the construction of invalid paths usingPath.with_name(). Original patch by Antony Lee.
• bpo-21897: Fix a crash with the f_locals attribute with closure variableswhen frame.clear() has been called.
• bpo-21151: Fixed a segfault in the winreg module whenNone is passedas aREG_BINARY value to SetValueEx. Patch by John Ehresman.
• bpo-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.
• bpo-21781: ssl.RAND_add() now supports strings longer than 2 GB.
• bpo-11453: asyncore: emit a ResourceWarning when an unclosed file_wrapperobject is destroyed. The destructor now closes the file if needed. Theclose() method can now be called twice: the second call does nothing.
• bpo-21858: Better handling of Python exceptions in the sqlite3 module.
• bpo-21476: Make sure the email.parser.BytesParser TextIOWrapper isdiscarded after parsing, so the input file isn’t unexpectedly closed.
• bpo-21729: Used the “with” statement in the dbm.dumb module to ensurefiles closing. Patch by Claudiu Popa.
• bpo-21491: socketserver: Fix a race condition in child processes reaping.
• bpo-21832: Require named tuple inputs to be exact strings.
• bpo-19145: The times argument for itertools.repeat now handles negativevalues the same way for keyword arguments as it does for positionalarguments.
• bpo-21812: turtle.shapetransform did not tranform the turtle on the firstcall. (Issue identified and fixed by Lita Cho.)
• bpo-21635: The difflib SequenceMatcher.get_matching_blocks() method cachedidn’t match the actual result. The former was a list of tuples and thelatter was a list of named tuples.
• bpo-21722: The distutils “upload” command now exits with a non-zero returncode when uploading fails. Patch by Martin Dengler.
• bpo-21723: asyncio.Queue: support any type of number (ex: float) for themaximum size. Patch written by Vajrasky Kok.
• bpo-21326: Add a new is_closed() method to asyncio.BaseEventLoop.run_forever() and run_until_complete() methods of asyncio.BaseEventLoopnow raise an exception if the event loop was closed.
• bpo-21774: Fixed NameError for an incorrect variable reference in the XMLMinidom code for creating processing instructions. (Found and fixed byClaudiu Popa.)
• bpo-21766: Prevent a security hole in CGIHTTPServer by URL unquoting pathsbefore checking for a CGI script at that path.
• bpo-21310: Fixed possible resource leak in failed open().
• bpo-21677: Fixed chaining nonnormalized exceptions in io close() methods.
• bpo-11709: Fix the pydoc.help function to not fail when sys.stdin is not avalid file.
• bpo-13223: Fix pydoc.writedoc so that the HTML documentation for methodsthat use ‘self’ in the example code is generated correctly.
• bpo-21463: In urllib.request, fix pruning of the FTP cache.
• bpo-21618: The subprocess module could fail to close open fds that wereinherited by the calling process and already higher than POSIX resourcelimits would otherwise allow. On systems with a functioning /proc/self/fdor /dev/fd interface the max is now ignored and all fds are closed.
• bpo-21552: Fixed possible integer overflow of too long string lengths inthe tkinter module on 64-bit platforms.
• bpo-14315: The zipfile module now ignores extra fields in the centraldirectory that are too short to be parsed instead of letting astruct.unpack error bubble up as this “bad data” appears in many realworld zip files in the wild and is ignored by other zip tools.
• bpo-21402: tkinter.ttk now works when default root window is not set.
• bpo-10203: sqlite3.Row now truly supports sequence protocol. Inparticular it supports reverse() and negative indices. Original patch byClaudiu Popa.
• bpo-18807: If copying (no symlinks) specified for a venv, then the pythoninterpreter aliases (python, python3) are now created by copying ratherthan symlinking.
• bpo-14710: pkgutil.get_loader() no longer raises an exception when None isfound in sys.modules.
• bpo-14710: pkgutil.find_loader() no longer raises an exception when amodule doesn’t exist.
• bpo-21481: Argparse equality and inequality tests now returnNotImplemented when comparing to an unknown type.
• bpo-8743: Fix interoperability between set objects and thecollections.Set() abstract base class.
• bpo-13355: random.triangular() no longer fails with a ZeroDivisionErrorwhen low equals high.
• bpo-21538: The plistlib module now supports loading of binary plist fileswhen reference or offset size is not a power of two.
• bpo-21801: Validate that __signature__ is None or an instance ofSignature.
• bpo-21923: Prevent AttributeError indistutils.sysconfig.customize_compiler due to possible uninitialized_config_vars.
• bpo-21323: Fix http.server to again handle scripts in CGI subdirectories,broken by the fix for securityissue #19435. Patch by Zach Byrne.
• bpo-22176: Update the ctypes module’s libffi to v3.1. This release addssupport for the Linux AArch64 and POWERPC ELF ABIv2 little endianarchitectures.

Build¶

• bpo-15661: python.org OS X installers are now distributed as signedinstaller packages compatible with the Gatekeeper security feature.
• bpo-21958: Define HAVE_ROUND when building with Visual Studio 2013 andabove. Patch by Zachary Turner.
• bpo-15759: “make suspicious”, “make linkcheck” and “make doctest” in Doc/now display special message when and only when there are failures.
• bpo-17095: Fix Modules/Setupshared support.
• bpo-21811: Anticipated fixes to support OS X versions > 10.9.
• bpo-21166: Prevent possible segfaults and other random failures of python–generate- posix-vars in pybuilddir.txt build target.

IDLE¶

• bpo-17390: Adjust Editor window title; remove ‘Python’, move version toend.
• bpo-14105: Idle debugger breakpoints no longer disappear when inseting ordeleting lines.
• bpo-17172: Turtledemo can now be run from Idle. Currently, the entry is onthe Help menu, but it may move to Run. Patch by Ramchandra Apt and LitaCho.
• bpo-21765: Add support for non-ascii identifiers to HyperParser.
• bpo-21940: Add unittest for WidgetRedirector. Initial patch by SaimadhavHeblikar.
• bpo-18592: Add unittest for SearchDialogBase. Patch by Phil Webster.
• bpo-21694: Add unittest for ParenMatch. Patch by Saimadhav Heblikar.
• bpo-21686: add unittest for HyperParser. Original patch by SaimadhavHeblikar.
• bpo-12387: Add missing upper(lower)case versions of default Windows keybindings for Idle so Caps Lock does not disable them. Patch by RogerSerwy.
• bpo-21695: Closing a Find-in-files output window while the search is stillin progress no longer closes Idle.
• bpo-18910: Add unittest for textView. Patch by Phil Webster.
• bpo-18292: Add unittest for AutoExpand. Patch by Saihadhav Heblikar.
• bpo-18409: Add unittest for AutoComplete. Patch by Phil Webster.

Tests¶

• bpo-22166: With the assistance of a new internal _codecs._forget_codechelping function, test_codecs now clears the encoding caches to avoid theappearance of a reference leak
• bpo-22236: Tkinter tests now don’t reuse default root window. New rootwindow is created for every test class.
• bpo-20746: Fix test_pdb to run in refleak mode (-R). Patch by Xavier deGaye.
• bpo-22060: test_ctypes has been somewhat cleaned up and simplified; it nowuses unittest test discovery to find its tests.
• bpo-22104: regrtest.py no longer holds a reference to the suite of testsloaded from test modules that don’t define test_main().
• bpo-22002: Addedload_package_tests function to test.support and usedit to implement/augment test discovery in test_asyncio, test_email,test_importlib, test_json, and test_tools.
• bpo-21976: Fix test_ssl to accept LibreSSL version strings. Thanks toWilliam Orr.
• bpo-21918: Converted test_tools from a module to a package containingseparate test files for each tested script.
• bpo-20155: Changed HTTP method names in failing tests in test_httpserversso that packet filtering software (specifically Windows Base FilteringEngine) does not interfere with the transaction semantics expected by thetests.
• bpo-19493: Refactored the ctypes test package to skip tests explicitlyrather than silently.
• bpo-18492: All resources are now allowed when tests are not run byregrtest.py.
• bpo-21634: Fix pystone micro-benchmark: use floor division instead of truedivision to benchmark integers instead of floating point numbers. Setpystone version to 1.2. Patch written by Lennart Regebro.
• bpo-21605: Added tests for Tkinter images.
• bpo-21493: Added test for ntpath.expanduser(). Original patch by ClaudiuPopa.
• bpo-19925: Added tests for the spwd module. Original patch by VajraskyKok.
• bpo-21522: Added Tkinter tests for Listbox.itemconfigure(),PanedWindow.paneconfigure(), and Menu.entryconfigure().

Documentation¶

• bpo-21777: The binary sequence methods on bytes and bytearray are nowdocumented explicitly, rather than assuming users will be able to derivethe expected behaviour from the behaviour of the corresponding strmethods.

Windows¶

• bpo-21671: The bundled version of OpenSSL has been updated to 1.0.1i. (Seealso: bpo-22160, CVE-2014-0224)
• bpo-10747: Use versioned labels in the Windows start menu. Patch by OliveKilburn.

Tools/Demos¶

• bpo-22201: Command-line interface of the zipfile module now correctlyextracts ZIP files with directory entries. Patch by Ryan Wilson.
• bpo-21906: Make Tools/scripts/md5sum.py work in Python 3. Patch by ZacharyWare.
• bpo-21629: Fix Argument Clinic’s “–converters” feature.

Core and Builtins¶

• bpo-21418: Fix a crash in the builtin function super() when called withoutargument and without current frame (ex: embedded Python).
• bpo-21425: Fix flushing of standard streams in the interactiveinterpreter.
• bpo-21435: In rare cases, when running finalizers on objects in cyclictrash a bad pointer dereference could occur due to a subtle flaw ininternal iteration logic.

Library¶

• bpo-10744: Fix PEP 3118 format strings on ctypes objects with a nontrivialshape.
• bpo-20998: Fixed re.fullmatch() of repeated single character pattern withignore case. Original patch by Matthew Barnett.
• bpo-21075: fileinput.FileInput now reads bytes from standard stream ifbinary mode is specified. Patch by Sam Kimbrel.
• bpo-21396: Fix TextIOWrapper(..., write_through=True) to not force aflush() on the underlying binary stream. Patch by akira.
• bpo-21470: Do a better job seeding the random number generator by usingenough bytes to span the full state space of the Mersenne Twister.
• bpo-21398: Fix an unicode error in the pydoc pager when the documentationcontains characters not encodable to the stdout encoding.

Tests¶

• bpo-17756: Fix test_code test when run from the installed location.
• bpo-17752: Fix distutils tests when run from the installed location.

IDLE¶

• bpo-18104: Add idlelib/idle_test/htest.py with a few sample tests to beginconsolidating and improving human-validated tests of Idle. Change otherfiles as needed to work with htest. Running the module as __main__ runsall tests.

Core and Builtins¶

• bpo-21274: Define PATH_MAX for GNU/Hurd in Python/pythonrun.c.
• bpo-21209: Fix sending tuples to custom generator objects with the yieldfrom syntax.
• bpo-21134: Fix segfault when str is called on an uninitializedUnicodeEncodeError, UnicodeDecodeError, or UnicodeTranslateError object.
• bpo-19537: Fix PyUnicode_DATA() alignment under m68k. Patch by AndreasSchwab.
• bpo-20929: Add a type cast to avoid shifting a negative number.
• bpo-20731: Properly position in source code files even if they are openedin text mode. Patch by Serhiy Storchaka.
• bpo-20637: Key-sharing now also works for instance dictionaries ofsubclasses. Patch by Peter Ingebretson.
• bpo-12546: Allow\x00 to be used as a fill character when using str,int, float, and complex __format__ methods.
• bpo-13598: Modify string.Formatter to support auto-numbering ofreplacement fields. It now matches the behavior of str.format() in thisregard. Patches by Phil Elson and Ramchandra Apte.

Library¶

• bpo-21088: Bugfix for curses.window.addch() regression in 3.4.0. Inporting to Argument Clinic, the first two arguments were reversed.
• bpo-21469: Reduced the risk of false positives in robotparser by checkingto make sure that robots.txt has been read or does not exist prior toreturning True in can_fetch().
• bpo-21321: itertools.islice() now releases the reference to the sourceiterator when the slice is exhausted. Patch by Anton Afanasyev.
• bpo-9815: assertRaises now tries to clear references to local variables inthe exception’s traceback.
• bpo-13204: Calling sys.flags.__new__ would crash the interpreter, now itraises a TypeError.
• bpo-19385: Make operations on a closed dbm.dumb database always raise thesame exception.
• bpo-21207: Detect when the os.urandom cached fd has been closed orreplaced, and open it anew.
• bpo-21291: subprocess’s Popen.wait() is now thread safe so that multiplethreads may be calling wait() or poll() on a Popen instance at the sametime without losing the Popen.returncode value.
• bpo-21127: Path objects can now be instantiated from str subclassinstances (such asnumpy.str_).
• bpo-15002: urllib.response object to use _TemporaryFileWrapper (and_TemporaryFileCloser) facility. Provides a better way to handle filedescriptor close. Patch contributed by Christian Theune.
• bpo-12220: mindom now raises a custom ValueError indicating it doesn’tsupport spaces in URIs instead of letting a ‘split’ ValueError bubble up.
• bpo-21239: patch.stopall() didn’t work deterministically when the samename was patched more than once.
• bpo-21222: Passing name keyword argument to mock.create_autospec nowworks.
• bpo-21197: Add lib64 -> lib symlink in venvs on 64-bit non-OS X POSIX.
• bpo-17498: Some SMTP servers disconnect after certain errors, violatingstrict RFC conformance. Instead of losing the error code when we issuethe subsequent RSET, smtplib now returns the error code and defers raisingthe SMTPServerDisconnected error until the next command is issued.
• bpo-17826: setting an iterable side_effect on a mock function created bycreate_autospec now works. Patch by Kushal Das.
• bpo-7776: FixHost: header and reconnection when usinghttp.client.HTTPConnection.set_tunnel(). Patch by Nikolaus Rath.
• bpo-20968: unittest.mock.MagicMock now supports division. Patch byJohannes Baiter.
• bpo-21529: Fix arbitrary memory access in JSONDecoder.raw_decode with anegative second parameter. Bug reported by Guido Vranken. (See also:CVE-2014-4616)
• bpo-21169: getpass now handles non-ascii characters that the input streamencoding cannot encode by re-encoding using the replace error handler.
• bpo-21171: Fixed undocumented filter API of the rot13 codec. Patch byBerker Peksag.
• bpo-21172: isinstance check relaxed from dict to collections.Mapping.
• bpo-21155: asyncio.EventLoop.create_unix_server() now raises a ValueErrorif path and sock are specified at the same time.
• bpo-21149: Improved thread-safety in logging cleanup during interpretershutdown. Thanks to Devin Jeanpierre for the patch.
• bpo-20145:assertRaisesRegex andassertWarnsRegex now raise aTypeError if the second argument is not a string or compiled regex.
• bpo-21058: Fix a leak of file descriptor intempfile.NamedTemporaryFile(), close the file descriptor ifio.open() fails
• bpo-21200: Return None from pkgutil.get_loader() when __spec__ is missing.
• bpo-21013: Enhance ssl.create_default_context() when used for server sidesockets to provide better security by default.
• bpo-20633: Replace relative import by absolute import.
• bpo-20980: Stop wrapping exception when using ThreadPool.
• bpo-21082: In os.makedirs, do not set the process-wide umask. Note thischanges behavior of makedirs when exist_ok=True.
• bpo-20990: Fix issues found by pyflakes for multiprocessing.
• bpo-21015: SSL contexts will now automatically select an elliptic curvefor ECDH key exchange on OpenSSL 1.0.2 and later, and otherwise default to“prime256v1”.
• bpo-20995: Enhance default ciphers used by the ssl module to enable bettersecurity an prioritize perfect forward secrecy.
• bpo-20884: Don’t assume that __file__ is defined on importlib.__init__.
• bpo-21499: Ignore __builtins__ in several test_importlib.test_api tests.
• bpo-20879: Delay the initialization of encoding and decoding tables forbase32, ascii85 and base85 codecs in the base64 module, and delay theinitialization of the unquote_to_bytes() table of the urllib.parse module,to not waste memory if these modules are not used.
• bpo-19157: Include the broadcast address in the usuable hosts for IPv6 inipaddress.
• bpo-11599: When an external command (e.g. compiler) fails, distutils nowprints out the whole command line (instead of just the command name) ifthe environment variable DISTUTILS_DEBUG is set.
• bpo-4931: distutils should not produce unhelpful “error: None” messagesanymore. distutils.util.grok_environment_error is kept but doc-deprecated.
• bpo-20875: Prevent possible gzip “‘read’ is not defined” NameError. Patchby Claudiu Popa.
• bpo-11558:email.message.Message.attach now returns a more usefulerror message ifattach is called on a message for whichis_multipart is False.
• bpo-20283: RE pattern methods now accept the string keyword parameters asdocumented. The pattern and source keyword parameters are left asdeprecated aliases.
• bpo-20778: Fix modulefinder to work with bytecode-only modules.
• bpo-20791: copy.copy() now doesn’t make a copy when the input is a bytesobject. Initial patch by Peter Otten.
• bpo-19748: On AIX, time.mktime() now raises an OverflowError for yearoutsize range [1902; 2037].
• bpo-20816: Fix inspect.getcallargs() to raise correct TypeError formissing keyword- only arguments. Patch by Jeremiah Lowin.
• bpo-20817: Fix inspect.getcallargs() to fail correctly if more than 3arguments are missing. Patch by Jeremiah Lowin.
• bpo-6676: Ensure a meaningful exception is raised when attempting to parsemore than one XML document per pyexpat xmlparser instance. (Originalpatches by Hirokazu Yamamoto and Amaury Forgeot d’Arc, with suggestedwording by David Gutteridge)
• bpo-21117: Fix inspect.signature to better support functools.partial. Dueto the specifics of functools.partial implementation,positional-or-keyword arguments passed as keyword arguments becomekeyword-only.
• bpo-21209: Fix asyncio.tasks.CoroWrapper to workaround a bug in yield-fromimplementation in CPythons prior to 3.4.1.
• asyncio: Add gi_{frame,running,code} properties to CoroWrapper (upstreamissue #163).
• bpo-21311: Avoid exception in _osx_support with non-standard compilerconfigurations. Patch by John Szakmeister.
• bpo-11571: Ensure that the turtle window becomes the topmost window whenlaunched on OS X.
• bpo-21276: posixmodule: Don’t define USE_XATTRS on KFreeBSD and the Hurd.
• bpo-21226: Set up modules properly in PyImport_ExecCodeModuleObject (andfriends).

IDLE¶

• bpo-21139: Change default paragraph width to 72, the PEP 8 recommendation.
• bpo-21284: Paragraph reformat test passes after user changes reformatwidth.
• bpo-17654: Ensure IDLE menus are customized properly on OS X fornon-framework builds and for all variants of Tk.

Build¶

• The Windows build now includes OpenSSL 1.0.1g
• bpo-21285: Refactor and fix curses configure check to always search in ancursesw directory.
• bpo-15234: For BerkelyDB and Sqlite, only add the found library andinclude directories if they aren’t already being searched. This avoids anexplicit runtime library dependency.
• bpo-20644: OS X installer build support for documentation build changes in3.4.1: assume externally supplied sphinx-build is available in /usr/bin.

C API¶

• bpo-20942: PyImport_ImportFrozenModuleObject() no longer sets __file__ tomatch what importlib does; this affects _frozen_importlib as well as anymodule loaded using imp.init_frozen().

Documentation¶

• bpo-17386: Expanded functionality of theDoc/make.bat script to makeit much more comparable toDoc/Makefile.
• bpo-21043: Remove the recommendation for specific CA organizations and tomention the ability to load the OS certificates.
• bpo-20765: Add missing documentation for PurePath.with_name() andPurePath.with_suffix().
• bpo-19407: New package installation and distribution guides based on thePython Packaging Authority tools. Existing guides have been retained aslegacy links from the distutils docs, as they still contain some requiredreference material for tool developers that isn’t recorded anywhere else.
• bpo-19697: Document cases where __main__.__spec__ is None.

Tests¶

• bpo-18604: Consolidated checks for GUI availability. All platforms now atleast check whether Tk can be instantiated when the GUI resource isrequested.
• bpo-21275: Fix a socket test on KFreeBSD.
• bpo-21223: Pass test_site/test_startup_imports when some of the extensionsare built as builtins.
• bpo-20635: Added tests for Tk geometry managers.
• Add test case for freeze.
• bpo-20743: Fix a reference leak in test_tcl.
• bpo-21097: Move test_namespace_pkgs into test_importlib.
• bpo-20939: Avoid various network test failures due to new redirect ofhttp://www.python.org/ tohttps://www.python.org: usehttp://www.example.com instead.
• bpo-20668: asyncio tests no longer rely on tests.txt file. (Patch byVajrasky Kok)
• bpo-21093: Prevent failures of ctypes test_macholib on OS X if a copy oflibz exists in $HOME/lib or /usr/local/lib.

Tools/Demos¶

• Add support foryieldfrom to 2to3.
• Add support for the PEP 465 matrix multiplication operator to 2to3.
• bpo-16047: Fix module exception list and __file__ handling in freeze.Patch by Meador Inge.
• bpo-11824: Consider ABI tags in freeze. Patch by Meador Inge.
• bpo-20535: PYTHONWARNING no longer affects the run_tests.py script. Patchby Arfrever Frehtes Taifersar Arahesis.

Library¶

• bpo-20939: Fix test_geturl failure in test_urllibnet due to new redirectofhttp://www.python.org/ tohttps://www.python.org.

Documentation¶

• Merge in all documentation changes since branching 3.4.0rc1.

Core and Builtins¶

• bpo-20786: Fix signatures for dict.__delitem__ and property.__delete__builtins.

Library¶

• bpo-20839: Don’t trigger a DeprecationWarning in the still supportedpkgutil.get_loader() API when __loader__ isn’t set on a module (nor whenpkgutil.find_loader() is called directly).

Build¶

• bpo-14512: Launch pydoc -b instead of pydocgui.pyw on Windows.
• bpo-20748: Uninstalling pip does not leave behind the pyc of theuninstaller anymore.
• bpo-20568: The Windows installer now installs the unversionedpipcommand in addition to the versionedpip3 andpip3.4 commands.
• bpo-20757: The ensurepip helper for the Windows uninstaller now skipsuninstalling pip (rather than failing) if the user has updated pip to adifferent version from the one bundled with ensurepip.
• bpo-20465: Update OS X and Windows installer builds to use SQLite 3.8.3.1.

Core and Builtins¶

• bpo-20625: Parameter names in __annotations__ were not mangled properly.Discovered by Jonas Wielicki, patch by Yury Selivanov.
• bpo-20261: In pickle, lookup __getnewargs__ and __getnewargs_ex__ on thetype of the object.
• bpo-20619: Give the AST nodes of keyword-only arguments a column and linenumber.
• bpo-20526: Revert changes ofissue #19466 which introduces a regression:don’t clear anymore the state of Python threads early during the Pythonshutdown.

Library¶

• bpo-20710: The pydoc summary line no longer displays the “self” parameterfor bound methods.
• bpo-20566: Change asyncio.as_completed() to use a Queue, to avoid O(N**2)behavior.
• bpo-20704: Implement new debug API in asyncio. Add new methodsBaseEventLoop.set_debug() and BaseEventLoop.get_debug(). Add support forsetting ‘asyncio.tasks._DEBUG’ variable with ‘PYTHONASYNCIODEBUG’environment variable.
• asyncio: Refactoring and fixes: BaseEventLoop.sock_connect() raises anerror if the address is not resolved; use __slots__ in Handle andTimerHandle; as_completed() and wait() raise TypeError if the passed listof Futures is a single Future; call_soon() and other ‘call_*()’ functionsraise TypeError if the passed callback is a coroutine function;_ProactorBasePipeTransport uses _FlowControlMixin;WriteTransport.set_write_buffer_size() calls _maybe_pause_protocol() toconsider pausing receiving if the watermark limits have changed; fix_check_resolved_address() for IPv6 address; and other minor improvements,along with multiple documentation updates.
• bpo-20684: Fix inspect.getfullargspec() to not to follow __wrapped__chains. Make its behaviour consistent with bound methods first argument.Patch by Nick Coghlan and Yury Selivanov.
• bpo-20681: Add new error handling API in asyncio. New APIs:loop.set_exception_handler(), loop.default_exception_handler(), andloop.call_exception_handler().
• bpo-20673: Implement support for UNIX Domain Sockets in asyncio. New APIs:loop.create_unix_connection(), loop.create_unix_server(),streams.open_unix_connection(), and streams.start_unix_server().
• bpo-20616: Add a format() method to tracemalloc.Traceback.
• bpo-19744: the ensurepip installation step now just prints a warning tostderr rather than failing outright if SSL/TLS is unavailable. This allowslocal installation of POSIX builds without SSL/TLS support.
• bpo-20594: Avoid name clash with the libc function posix_close.

Build¶

• bpo-20641: Run MSI custom actions (pip installation, pyc compilation) withthe NoImpersonate flag, to support elevated execution (UAC).
• bpo-20221: Removed conflicting (or circular) hypot definition whencompiled with VS 2010 or above. Initial patch by Tabrez Mohammed.
• bpo-20609: Restored the ability to build 64-bit Windows binaries on 32-bitWindows, which was broken by the change inissue #19788.

Core and Builtins¶

• bpo-19255: The builtins module is restored to initial value beforecleaning other modules. The sys and builtins modules are cleaned last.
• bpo-20588: Make Python-ast.c C89 compliant.
• bpo-20437: Fixed 22 potential bugs when deleting objects references.
• bpo-20500: Displaying an exception at interpreter shutdown no longer riskstriggering an assertion failure in PyObject_Str.
• bpo-20538: UTF-7 incremental decoder produced inconsistent string wheninput was truncated in BASE64 section.
• bpo-20404: io.TextIOWrapper (and hence the open() builtin) now uses theinternal codec marking system added forissue #19619 to throw LookupErrorfor known non- text encodings at stream construction time. The existingoutput type checks remain in place to deal with unmarked third partycodecs.
• bpo-17162: Add PyType_GetSlot.
• bpo-20162: Fix an alignment issue in the siphash24() hash function whichcaused a crash on PowerPC 64-bit (ppc64).

Library¶

• bpo-20530: The signatures for slot builtins have been updated to reflectthe fact that they only accept positional-only arguments.
• bpo-20517: Functions in the os module that accept two filenames nowregister both filenames in the exception on failure.
• bpo-20563: The ipaddress module API is now considered stable.
• bpo-14983: email.generator now always adds a line end after each MIMEboundary marker, instead of doing so only when there is an epilogue. Thisfixes an RFC compliance bug and solves an issue with signed MIME parts.
• bpo-20540: Fix a performance regression (vs. Python 3.2) when layering amultiprocessing Connection over a TCP socket. For small payloads, Nagle’salgorithm would introduce idle delays before the entire transmission of amessage.
• bpo-16983: the new email header parsing code will now decode encoded wordsthat are (incorrectly) surrounded by quotes, and register a defect.
• bpo-19772: email.generator no longer mutates the message object when doinga down- transform from 8bit to 7bit CTEs.
• bpo-20536: the statistics module now correctly handle Decimal instanceswith positive exponents
• bpo-18805: the netmask/hostmask parsing in ipaddress now more reliablyfilters out illegal values and correctly allows any valid prefix length.
• bpo-20481: For at least Python 3.4, the statistics module will requirethat all inputs for a single operation be of a single consistent type, orelse a mixed of ints and a single other consistent type. This avoids someinteroperability issues that arose with the previous approach of coercingto a suitable common type.
• bpo-20478: the statistics module now treats collections.Counter inputslike any other iterable.
• bpo-17369: get_filename was raising an exception if the filenameparameter’s RFC2231 encoding was broken in certain ways. This was aregression relative to python2.
• bpo-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.
• bpo-20531: Revert 3.4 version of fix for #19063, and apply the 3.3version. That is, donot raise an error if unicode is passed toemail.message.Message.set_payload.
• bpo-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 shouldreally come from the policy; that will get fixed in 3.5.
• bpo-19920: TarFile.list() no longer fails when outputs a listingcontaining non- encodable characters. Based on patch by Vajrasky Kok.
• bpo-20515: Fix NULL pointer dereference introduced byissue #20368.
• bpo-19186: Restore namespacing of expat symbols inside the pyexpat module.
• bpo-20053: ensurepip (and hence venv) are no longer affected by thesettings in the default pip configuration file.
• bpo-20426: When passing the re.DEBUG flag, re.compile() displays the debugoutput every time it is called, regardless of the compilation cache.
• bpo-20368: The null character now correctly passed from Tcl to Python.Improved error handling in variables-related commands.
• bpo-20435: Fix _pyio.StringIO.getvalue() to take into account newlinetranslation settings.
• tracemalloc: Fix slicing traces and fix slicing a traceback.
• bpo-20354: Fix an alignment issue in the tracemalloc module on 64-bitplatforms. Bug seen on 64-bit Linux when using “make profile-opt”.
• bpo-17159: inspect.signature now accepts duck types of functions, whichadds support for Cython functions. Initial patch by Stefan Behnel.
• bpo-18801: Fix inspect.classify_class_attrs to correctly classifyobject.__new__ and object.__init__.
• Fixed cmath.isinf’s name in its argument parsing code.
• bpo-20311: poll and epoll now round the timeout away from zero, instead ofrounding towards zero, in select and selectors modules:select.epoll.poll(), selectors.PollSelector.poll() andselectors.EpollSelector.poll(). For example, a timeout of one microsecond(1e-6) is now rounded to one millisecondi (1e-3), instead of being roundedto zero. However, the granularity property and asyncio’s resolutionfeature were removed again. (See also: bpo-20452)
• asyncio: Some refactoring; various fixes; add write flow control to unixpipes; Future.set_exception() instantiates the exception argument if it isa class; improved proactor pipe transport; support wait_for(f, None);don’t log broken/disconnected pipes; use ValueError instead of assert forforbidden subprocess_{shell,exec} arguments; added a convenience API forsubprocess management; added StreamReader.at_eof(); properly handleduplicate coroutines/futures in gather(), wait(), as_completed(); use abytearray for buffering in StreamReader; and more.
• bpo-20288: fix handling of invalid numeric charrefs in HTMLParser.
• bpo-20424: Python implementation of io.StringIO now supports lonesurrogates.
• bpo-20308: inspect.signature now works on classes without user-defined__init__ or __new__ methods.
• bpo-20372: inspect.getfile (and a bunch of other inspect functions thatuse it) doesn’t crash with unexpected AttributeError on classes defined inC without __module__.
• bpo-20356: inspect.signature formatting uses ‘/’ to separatepositional-only parameters from others.
• bpo-20223: inspect.signature now supports methods defined withfunctools.partialmethods.
• bpo-19456: ntpath.join() now joins relative paths correctly when a driveis present.
• bpo-19077: tempfile.TemporaryDirectory cleanup no longer fails when calledduring shutdown. Emitting resource warning in __del__ no longer fails.Original patch by Antoine Pitrou.
• bpo-20394: Silence Coverity warning in audioop module.
• bpo-20367: Fix behavior of concurrent.futures.as_completed() for duplicatearguments. Patch by Glenn Langford.
• bpo-8260: The read(), readline() and readlines() methods ofcodecs.StreamReader returned incomplete data when were called afterreadline() or read(size). Based on patch by Amaury Forgeot d’Arc.
• bpo-20105: the codec exception chaining now correctly sets the tracebackof the original exception as its __traceback__ attribute.
• bpo-17481: inspect.getfullargspec() now uses inspect.signature() API.
• bpo-15304: concurrent.futures.wait() can block forever even if Futureshave completed. Patch by Glenn Langford.
• bpo-14455: plistlib: fix serializing integers in the range of an unsignedlong long but outside of the range of signed long long for binary plistfiles.

IDLE¶

• bpo-20406: Use Python application icons for Idle window title bars. Patchmostly by Serhiy Storchaka.
• Update the python.gif icon for the Idle classbrowser and pathbowser fromthe old green snake to the new blue and yellow snakes.
• bpo-17721: Remove non-functional configuration dialog help button until wemake it actually gives some help when clicked. Patch by Guilherme Simões.

Tests¶

• bpo-20532: Tests which use _testcapi now are marked as CPython only.
• bpo-19920: Added tests for TarFile.list(). Based on patch by VajraskyKok.
• bpo-19990: Added tests for the imghdr module. Based on patch by ClaudiuPopa.
• bpo-20474: Fix test_socket “unexpected success” failures on OS X 10.7+.

Tools/Demos¶

• bpo-20530: Argument Clinic’s signature format has been revised again. Thenew syntax is highly human readable while still preventing falsepositives. The syntax also extends Python syntax to denote “self” andpositional-only parameters, allowing inspect.Signature objects to betotally accurate for all supported builtins in Python 3.4.
• bpo-20456: Argument Clinic now observes the C preprocessor conditionalcompilation statements of the C files it parses. When a Clinic block isinside a conditional code, it adjusts its output to match, includingautomatically generating an empty methoddef macro.
• bpo-20456: Cloned functions in Argument Clinic now use the correct name,not the name of the function they were cloned from, for text stringsinside generated code.
• bpo-20456: Fixed Argument Clinic’s test suite and “–converters” feature.
• bpo-20456: Argument Clinic now allows specifying different names for aparameter in Python and C, using “as” on the parameter line.
• bpo-20326: Argument Clinic now uses a simple, unique signature to annotatetext signatures in docstrings, resulting in fewer false positives. “self”parameters are also explicitly marked, allowing inspect.Signature() toauthoritatively detect (and skip) said parameters.
• bpo-20326: Argument Clinic now generates separate checksums for the inputand output sections of the block, allowing external tools to verify thatthe input has not changed (and thus the output is not out-of-date).

Build¶

• bpo-20465: Update SQLite shipped with OS X installer to 3.8.3.

C API¶

• bpo-20517: Added new functions allowing OSError exceptions to referencetwo filenames instead of one: PyErr_SetFromErrnoWithFilenameObjects() andPyErr_SetExcFromWindowsErrWithFilenameObjects().

Documentation¶

• bpo-20488: Change wording to say importlib isthe implementation ofimport instead of justan implementation.
• bpo-6386: Clarify in the tutorial that specifying a symlink to executemeans the directory containing the executed script and not the symlink isadded to sys.path.

Core and Builtins¶

• bpo-20189: Four additional builtin types (PyTypeObject,PyMethodDescr_Type, _PyMethodWrapper_Type, and PyWrapperDescr_Type) havebeen modified to provide introspection information for builtins.
• bpo-17825: Cursor “^” is correctly positioned for SyntaxError andIndentationError.
• bpo-2382: SyntaxError cursor “^” is now written at correct position inmost cases when multibyte characters are in line (before “^”). This stillnot works correctly with wide East Asian characters.
• bpo-18960: The first line of Python script could be executed twice whenthe source encoding was specified on the second line. Now the sourceencoding declaration on the second line isn’t effective if the first linecontains anything except a comment. ‘python -x’ works now again withfiles with the source encoding declarations, and can be used to makePython batch files on Windows.

Library¶

• asyncio: Various improvements and small changes not all covered by issueslisted below. E.g. wait_for() now cancels the inner task if the timeoutocccurs; tweaked the set of exported symbols; renamed Empty/Full toQueueEmpty/QueueFull; “with (yield from lock)” now uses a separate contextmanager; readexactly() raises if not enough data was read; PTY supporttweaks.
• bpo-20311: asyncio: Add a granularity attribute to BaseEventLoop: maximumbetween the resolution of the BaseEventLoop.time() method and theresolution of the selector. The granuarility is used in the scheduler toround time and deadline.
• bpo-20311: selectors: Add a resolution attribute to BaseSelector.
• bpo-20189: unittest.mock now no longer assumes that any object for whichit could get an inspect.Signature is a callable written in Python. Fixcourtesy of Michael Foord.
• bpo-20317: ExitStack.__exit__ could create a self-referential loop if anexception raised by a cleanup operation already had its context setcorrectly (for example, by the @contextmanager decorator). The infiniteloop this caused is now avoided by checking if the expected context isalready set before trying to fix it.
• bpo-20374: Fix build with GNU readline >= 6.3.
• bpo-20262: Warnings are raised now when duplicate names are added in theZIP file or too long ZIP file comment is truncated.
• bpo-20165: The unittest module no longer considers tests marked with@expectedFailure successful if they pass.
• bpo-18574: Added missing newline in 100-Continue reply fromhttp.server.BaseHTTPRequestHandler. Patch by Nikolaus Rath.
• bpo-20270: urllib.urlparse now supports empty ports.
• bpo-20243: TarFile no longer raise ReadError when opened in write mode.
• bpo-20238: TarFile opened with external fileobj and “w:gz” mode didn’twrite complete output on close.
• bpo-20245: The open functions in the tarfile module now correctly handleempty mode.
• bpo-20242: Fixed basicConfig() format strings for the alternativeformatting styles. Thanks to kespindler for the bug report and patch.
• bpo-20246: Fix buffer overflow in socket.recvfrom_into.
• bpo-20206: Fix edge case in email.quoprimime.encode where it truncatedlines ending in a character needing encoding but no newline by using amore efficient algorithm that doesn’t have the bug. (See also: bpo-5803)
• bpo-19082: Working xmlrpc.server and xmlrpc.client examples. Both inmodules and in documentation. Initial patch contributed by Vajrasky Kok.
• bpo-20138: The wsgiref.application_uri() and wsgiref.request_uri()functions now conform to PEP 3333 when handle non-ASCII URLs.
• bpo-19097: Raise the correct Exception when cgi.FieldStorage is given aninvalid fileobj.
• bpo-20152: Ported Python/import.c over to Argument Clinic.
• bpo-13107: argparse and optparse no longer raises an exception when outputa help on environment with too small COLUMNS. Based on patch by ElazarGershuni.
• bpo-20207: Always disable SSLv2 except when PROTOCOL_SSLv2 is explicitlyasked for.
• bpo-18960: The tokenize module now ignore the source encoding declarationon the second line if the first line contains anything except a comment.
• bpo-20078: Reading malformed zipfiles no longer hangs with 100% CPUconsumption.
• bpo-20113: os.readv() and os.writev() now raise an OSError exception onerror instead of returning -1.
• bpo-19719: Make importlib.abc.MetaPathFinder.find_module(),PathEntryFinder.find_loader(), and Loader.load_module() use PEP 451 APIsto help with backwards-compatibility.
• bpo-20144: inspect.Signature now supports parsing simple symbolicconstants as parameter default values in __text_signature__.
• bpo-20072: Fixed multiple errors in tkinter with wantobjects is False.
• bpo-20229: Avoid plistlib deprecation warning in platform.mac_ver().
• bpo-14455: Fix some problems with the new binary plist support inplistlib.

IDLE¶

• bpo-17390: Add Python version to Idle editor window title bar. Originalpatches by Edmond Burnett and Kent Johnson.
• bpo-18960: IDLE now ignores the source encoding declaration on the secondline if the first line contains anything except a comment.

Tests¶

• bpo-20358: Tests for curses.window.overlay and curses.window.overwrite nolonger specify min{row,col} > max{row,col}.
• bpo-19804: The test_find_mac test in test_uuid is now skipped if theifconfig executable is not available.
• bpo-19886: Use better estimated memory requirements for bigmem tests.

Tools/Demos¶

• bpo-20390: Argument Clinic’s “file” output preset now defaults to“{dirname}/clinic/{basename}.h”.
• bpo-20390: Argument Clinic’s “class” directive syntax has been extendedwith two new required arguments: “typedef” and “type_object”.
• bpo-20390: Argument Clinic: If __new__ or __init__ functions didn’t usekwargs (or args), the PyArg_NoKeywords (or PyArg_NoPositional) callsgenerated are only run when the type object is an exact match.
• bpo-20390: Argument Clinic now fails if you have required parameters afteroptional parameters.
• bpo-20390: Argument Clinic converters now have a new template they caninject code into: “modifiers”. Code put there is run in the parsingfunction after argument parsing but before the call to the impl.
• bpo-20376: Argument Clinic now escapes backslashes in docstrings.
• bpo-20381: Argument Clinic now sanity checks the default argument whenc_default is also specified, providing a nice failure message fordisallowed values.
• bpo-20189: Argument Clinic now ensures that parser functions for __new__are always of type newfunc, the type of the tp_new slot. Similarly, parserfunctions for __init__ are now always of type initproc, the type oftp_init.
• bpo-20189: Argument Clinic now suppresses the docstring for __new__ and__init__ functions if no docstring is provided in the input.
• bpo-20189: Argument Clinic now suppresses the “self” parameter in the implfor @staticmethod functions.
• bpo-20294: Argument Clinic now supports argument parsing for __new__ and__init__ functions.
• bpo-20299: Argument Clinic custom converters may now change the defaultvalue of c_default and py_default with a class member.
• bpo-20287: Argument Clinic’s output is now configurable, allowing delayingits output or even redirecting it to a separate file.
• bpo-20226: Argument Clinic now permits simple expressions (e.g.“sys.maxsize - 1”) as default values for parameters.
• bpo-19936: Added executable bits or shebang lines to Python scripts whichrequires them. Disable executable bits and shebang lines in test andbenchmark files in order to prevent using a random system python, and insource files of modules which don’t provide command line interface. Fixedshebang lines in the unittestgui and checkpip scripts.
• bpo-20268: Argument Clinic now supports cloning the parameters and returnconverter of existing functions.
• bpo-20228: Argument Clinic now has special support for class specialmethods.
• bpo-20214: Fixed a number of small issues and documentation errors inArgument Clinic (see issue for details).
• bpo-20196: Fixed a bug where Argument Clinic did not generate correctparsing code for functions with positional-only parameters where allarguments are optional.
• bpo-18960: 2to3 and the findnocoding.py script now ignore the sourceencoding declaration on the second line if the first line containsanything except a comment.
• bpo-19723: The marker comments Argument Clinic uses have been changed toimprove readability.
• bpo-20157: When Argument Clinic renames a parameter because its namecollides with a C keyword, it no longer exposes that rename toPyArg_Parse.
• bpo-20141: Improved Argument Clinic’s support for the PyArg_Parse “O!”format unit.
• bpo-20144: Argument Clinic now supports simple symbolic constants asparameter default values.
• bpo-20143: The line numbers reported in Argument Clinic errors are nowmore accurate.
• bpo-20142: Py_buffer variables generated by Argument Clinic are nowinitialized with a default value.

Build¶

• bpo-12837: Silence a tautological comparison warning on OS X under Clangin socketmodule.c.

Core and Builtins¶

• bpo-17432: Drop UCS2 from names of Unicode functions in python3.def.
• bpo-19526: Exclude all new API from the stable ABI. Exceptions can be madeif a need is demonstrated.
• bpo-19969: PyBytes_FromFormatV() now raises an OverflowError if “%c”argument is not in range [0; 255].
• bpo-19995: %c, %o, %x, and %X now issue a DeprecationWarning onnon-integer input; reworded docs to clarify that an integer type shoulddefine both __int__ and __index__.
• bpo-19787: PyThread_set_key_value() now always set the value. In Python3.3, the function did nothing if the key already exists (if the currentvalue is a non-NULL pointer).
• bpo-14432: Remove the thread state field from the frame structure. Fix acrash when a generator is created in a C thread that is destroyed whilethe generator is still used. The issue was that a generator contains aframe, and the frame kept a reference to the Python state of the destroyedC thread. The crash occurs when a trace function is setup.
• bpo-19576: PyGILState_Ensure() now initializes threads. At startup, Pythonhas no concrete GIL. If PyGILState_Ensure() is called from a new threadfor the first time and PyEval_InitThreads() was not called yet, a GILneeds to be created.
• bpo-17576: Deprecation warning emitted now when __int__() or __index__()return not int instance.
• bpo-19932: Fix typo in import.h, missing whitespaces in functionprototypes.
• bpo-19736: Add module-level statvfs constants defined for GNU/glibc basedsystems.
• bpo-20097: Fix bad use of “self” in importlib’s WindowsRegistryFinder.
• bpo-19729: In str.format(), fix recursive expansion in format spec.
• bpo-19638: Fix possible crash / undefined behaviour from huge (more than 2billion characters) input strings in _Py_dg_strtod.

Library¶

• bpo-20154: Deadlock in asyncio.StreamReader.readexactly().
• bpo-16113: Remove sha3 module again.
• bpo-20111: pathlib.Path.with_suffix() now sanity checks the given suffix.
• Fix breakage in TestSuite.countTestCases() introduced byissue #11798.
• bpo-20108: Avoid parameter name clash in inspect.getcallargs().
• bpo-19918: Fix PurePath.relative_to() under Windows.
• bpo-19422: Explicitly disallow non-SOCK_STREAM sockets in the ssl module,rather than silently let them emit clear text data.
• bpo-20046: Locale alias table no longer contains entities which can becalculated. Generalized support of the euro modifier.
• bpo-20027: Fixed locale aliases for devanagari locales.
• bpo-20067: Tkinter variables now work when wantobjects is false.
• bpo-19020: Tkinter now uses splitlist() instead of split() in configuremethods.
• bpo-19744: ensurepip now provides a better error message when Python isbuilt without SSL/TLS support (pip currently requires that support to run,even if only operating with local wheel files)
• bpo-19734: ensurepip now ignores all pip environment variables to avoidodd behaviour based on user configuration settings
• Fix TypeError on “setup.py upload –show-response”.
• bpo-20045: Fix “setup.py register –list-classifiers”.
• bpo-18879: When a method is looked up on a temporary file, avoid closingthe file before the method is possibly called.
• bpo-20037: Avoid crashes when opening a text file late at interpretershutdown.
• bpo-19967: Thanks to the PEP 442, asyncio.Future now uses a destructor tolog uncaught exceptions, instead of the dedicated _TracebackLogger class.
• Added a Task.current_task() class method to asyncio.
• bpo-19850: Set SA_RESTART in asyncio when registering a signal handler tolimit EINTR occurrences.
• Implemented write flow control in asyncio for proactor event loop(Windows).
• Change write buffer in asyncio use to avoid O(N**2) behavior. Makewrite()/sendto() accept bytearray/memoryview.
• bpo-20034: Updated alias mapping to most recent locale.alias file fromX.org distribution using makelocalealias.py.
• bpo-5815: Fixed support for locales with modifiers. Fixed support forlocale encodings with hyphens.
• bpo-20026: Fix the sqlite module to handle correctly invalid isolationlevel (wrong type).
• bpo-18829: csv.Dialect() now checks type for delimiter, escapechar andquotechar fields. Original patch by Vajrasky Kok.
• bpo-19855: uuid.getnode() on Unix now looks on the PATH for theexecutables used to find the mac address, with /sbin and /usr/sbin asfallbacks.
• bpo-20007: HTTPResponse.read(0) no more prematurely closes connection.Original patch by Simon Sapin.
• bpo-19946: multiprocessing now uses runpy to initialize __main__ in childprocesses when necessary, allowing it to correctly handle scripts withoutsuffixes and submodules that use explicit relative imports or otherwiserely on parent modules being correctly imported prior to execution.
• bpo-19921: When Path.mkdir() is called with parents=True, any missingparent is created with the default permissions, ignoring the mode argument(mimicking the POSIX “mkdir -p” command).
• bpo-19887: Improve the Path.resolve() algorithm to support certain symlinkchains.
• bpo-19912: Fixed numerous bugs in ntpath.splitunc().
• bpo-19911: ntpath.splitdrive() now correctly processes the ‘İ’ character(U+0130, LATIN CAPITAL LETTER I WITH DOT ABOVE).
• bpo-19532: python -m compileall with no filename/directory arguments nowrespects the -f and -q flags instead of ignoring them.
• bpo-19623: Fixed writing to unseekable files in the aifc module.
• bpo-19946: multiprocessing.spawn now raises ImportError when the module tobe used as the main module cannot be imported.
• bpo-17919: select.poll.register() again works with poll.POLLNVAL on AIX.Fixed integer overflow in the eventmask parameter.
• bpo-19063: if a Charset’s body_encoding was set to None, the email packagewould generate a message claiming the Content-Transfer-Encoding was 7bit,and produce garbage output for the content. This now works. A couple ofother set_payload mishandlings of non-ASCII are also fixed. In addition,calling set_payload with a string argument without specifying a charsetnow raises an error (this is a new error in 3.4).
• bpo-15475: Add __sizeof__ implementations for itertools objects.
• bpo-19944: Fix importlib.find_spec() so it imports parents as needed andmove the function to importlib.util.
• bpo-19880: Fix a reference leak in unittest.TestCase. Explicitly breakreference cycles between frames and the _Outcome instance.
• bpo-17429: platform.linux_distribution() now decodes files from the UTF-8encoding with the surrogateescape error handler, instead of decoding fromthe locale encoding in strict mode. It fixes the function on Fedora 19which is probably the first major distribution release with a non-ASCIIname. Patch written by Toshio Kuratomi.
• bpo-19343: Expose FreeBSD-specific APIs in resource module. Originalpatch by Koobs.
• bpo-19929: Call os.read with 32768 within subprocess.Popen.communicaterather than 4096 for efficiency. A microbenchmark shows Linux and OS Xboth using ~50% less cpu time this way.
• bpo-19506: Use a memoryview to avoid a data copy when piping data to stdinwithin subprocess.Popen.communicate. 5-10% less cpu usage.
• bpo-19876: selectors unregister() no longer raises ValueError or OSErrorif the FD is closed (as long as it was registered).
• bpo-19908: pathlib now joins relative Windows paths correctly when a driveis present. Original patch by Antoine Pitrou.
• bpo-19296: Silence compiler warning in dbm_open
• bpo-6784: Strings from Python 2 can now be unpickled as bytes objects bysetting the encoding argument of Unpickler to be ‘bytes’. Initial patch byMerlijn van Deen.
• bpo-19839: Fix regression in bz2 module’s handling of non-bzip2 data atEOF, and analogous bug in lzma module.
• bpo-19881: Fix pickling bug where cpickle would emit bad pickle data forlarge bytes string (i.e., with size greater than 2**32-1).
• bpo-19138: doctest’s IGNORE_EXCEPTION_DETAIL now allows a match when noexception detail exists (no colon following the exception’s name, or acolon does follow but no text follows the colon).
• bpo-19927: Add __eq__ to path-based loaders in importlib.
• bpo-19827: On UNIX, setblocking() and settimeout() methods ofsocket.socket can now avoid a second syscall if the ioctl() function canbe used, or if the non- blocking flag of the socket is unchanged.
• bpo-19785: smtplib now supports SSLContext.check_hostname and server nameindication for TLS/SSL connections.
• bpo-19784: poplib now supports SSLContext.check_hostname and server nameindication for TLS/SSL connections.
• bpo-19783: nntplib now supports SSLContext.check_hostname and server nameindication for TLS/SSL connections.
• bpo-19782: imaplib now supports SSLContext.check_hostname and server nameindication for TLS/SSL connections.
• bpo-20123: Fix pydoc.synopsis() for “binary” modules.
• bpo-19834: Support unpickling of exceptions pickled by Python 2.
• bpo-19781: ftplib now supports SSLContext.check_hostname and server nameindication for TLS/SSL connections.
• bpo-19509: Add SSLContext.check_hostname to match the peer’s certificatewith server_hostname on handshake.
• bpo-15798: Fixed subprocess.Popen() to no longer fail if file descriptor0, 1 or 2 is closed.
• bpo-17897: Optimized unpickle prefetching.
• bpo-3693: Make the error message more helpful when the array.array()constructor is given a str. Move the array module typecode documentationto the docstring of the constructor.
• bpo-19088: Fixed incorrect caching of the copyreg module inobject.__reduce__() and object.__reduce_ex__().
• bpo-19698: Removed exec_module() methods fromimportlib.machinery.BuiltinImporter and ExtensionFileLoader.
• bpo-18864: Added a setter for ModuleSpec.has_location.
• Fixed _pickle.Unpickler to not fail when loading empty strings aspersistent IDs.
• bpo-11480: Fixed copy.copy to work with classes with custom metaclasses.Patch by Daniel Urban.
• bpo-6477: Added support for pickling the types of built-in singletons(i.e., Ellipsis, NotImplemented, None).
• bpo-19713: Add remaining PEP 451-related deprecations and move away fromusing find_module/find_loaer/load_module.
• bpo-19708: Update pkgutil to use the new importer APIs.
• bpo-19703: Update pydoc to use the new importer APIs.
• bpo-19851: Fixed a regression in reloading sub-modules.
• ssl.create_default_context() sets OP_NO_COMPRESSION to prevent CRIME.
• bpo-19802: Add socket.SO_PRIORITY.
• bpo-11508: Fixed uuid.getnode() and uuid.uuid1() on environment withvirtual interface. Original patch by Kent Frazier.
• bpo-11489: JSON decoder now accepts lone surrogates.
• bpo-19545: Avoid chained exceptions while passing stray % totime.strptime(). Initial patch by Claudiu Popa.

IDLE¶

• bpo-20058: sys.stdin.readline() in IDLE now always returns only one line.
• bpo-19481: print() of string subclass instance in IDLE no longer hangs.
• bpo-18270: Prevent possible IDLE AttributeError on OS X when no initialshell window is present.

Tests¶

• bpo-20055: Fix test_shutil under Windows with symlink privileges held.Patch by Vajrasky Kok.
• bpo-20070: Don’t run test_urllib2net when network resources are notenabled.
• bpo-19938: Re-enabled test_bug_1333982 in test_dis, which had beendisabled since 3.0 due to the changes in listcomp handling.
• bpo-19320: test_tcl no longer fails when wantobjects is false.
• bpo-19919: Fix flaky SSL test. connect_ex() sometimes returns EWOULDBLOCKon Windows or VMs hosted on Windows.
• bpo-19912: Added tests for ntpath.splitunc().
• bpo-19828: Fixed test_site when the whole suite is run with -S.
• bpo-19928: Implemented a test for repr() of cell objects.
• bpo-19535: Fixed test_docxmlrpc, test_functools, test_inspect, andtest_statistics when python is run with -OO.
• bpo-19926: Removed unneeded test_main from test_abstract_numbers. Patch byVajrasky Kok.
• bpo-19572: More skipped tests explicitly marked as skipped.
• bpo-19595: Re-enabled a long-disabled test in test_winsound. (See also:bpo-19987)
• bpo-19588: Fixed tests in test_random that were silently skipped most ofthe time. Patch by Julian Gindi.

Build¶

• bpo-19728: Enable pip installation by default on Windows.
• bpo-16136: Remove VMS support
• bpo-18215: Add script Tools/ssl/test_multiple_versions.py to compile andrun Python’s unit tests with multiple versions of OpenSSL.
• bpo-19922: define _INCLUDE__STDC_A1_SOURCE in HP-UX to include mbstate_tfor mbrtowc().
• bpo-19788: kill_python(_d).exe is now run as a PreBuildEvent on thepythoncore sub- project. This should prevent build errors due a previousbuild’s python(_d).exe still running.

Documentation¶

• bpo-20265: Updated some parts of the Using Windows document.
• bpo-20266: Updated some parts of the Windows FAQ.
• bpo-20255: Updated the about and bugs pages.
• bpo-20253: Fixed a typo in the ipaddress docs that advertised an illegalattribute name. Found by INADA Naoki.
• bpo-18840: Introduce the json module in the tutorial, and de-emphasize thepickle module.
• bpo-19845: Updated the Compiling Python on Windows section.
• bpo-19795: Improved markup of True/False constants.

Tools/Demos¶

• bpo-19659: Added documentation for Argument Clinic.
• bpo-19976: Argument Clinic METH_NOARGS functions now always take twoparameters.

Core and Builtins¶

• Use the repr of a module name in more places in import, especiallyexceptions.
• bpo-19619: str.encode, bytes.decode and bytearray.decode now use aninternal API to throw LookupError for known non-text encodings, ratherthan attempting the encoding or decoding operation and then throwing aTypeError for an unexpected output type. (The latter mechanism remains inplace for third party non-text encodings)
• bpo-19183: Implement PEP 456 ‘secure and interchangeable hash algorithm’.Python now uses SipHash24 on all major platforms.
• bpo-12892: The utf-16* and utf-32* encoders no longer allow surrogate codepoints (U+D800-U+DFFF) to be encoded. The utf-32* decoders no longerdecode byte sequences that correspond to surrogate code points. Thesurrogatepass error handler now works with the utf-16* and utf-32* codecs.Based on patches by Victor Stinner and Kang-Hao (Kenny) Lu.
• bpo-17806: Added keyword-argument support for “tabsize” tostr/bytes.expandtabs().
• bpo-17828: Output type errors in str.encode(), bytes.decode() andbytearray.decode() now direct users to codecs.encode() or codecs.decode()as appropriate.
• bpo-17828: The interpreter now attempts to chain errors that occur incodec processing with a replacement exception of the same type thatincludes the codec name in the error message. It ensures it only does thiswhen the creation of the replacement exception won’t lose any information.
• bpo-19466: Clear the frames of daemon threads earlier during the Pythonshutdown to call objects destructors. So “unclosed file” resource warningsare now corretly emitted for daemon threads.
• bpo-19514: Deduplicate some _Py_IDENTIFIER declarations. Patch by AndreiDorian Duma.
• bpo-17936: Fix O(n**2) behaviour when adding or removing many subclassesof a given type.
• bpo-19428: zipimport now handles errors when reading truncated or invalidZIP archive.
• bpo-18408: Add a new PyFrame_FastToLocalsWithError() function to handleexceptions when merging fast locals into f_locals of a frame.PyEval_GetLocals() now raises an exception and return NULL on failure.
• bpo-19369: Optimized the usage of __length_hint__().
• bpo-18603: Ensure that PyOS_mystricmp and PyOS_mystrnicmp are in thePython executable and not removed by the linker’s optimizer.
• bpo-19306: Add extra hints to the faulthandler module’s stack dumps thatthese are “upside down”.

Library¶

• bpo-3158: doctest can now find doctests in functions and methods writtenin C.
• bpo-13477: Added command line interface to the tarfile module. Originalpatch by Berker Peksag.
• bpo-19674: inspect.signature() now produces a correct signature for somebuiltins.
• bpo-19722: Added opcode.stack_effect(), which computes the stack effect ofbytecode instructions.
• bpo-19735: Implement private function ssl._create_stdlib_context() tocreate SSLContext objects in Python’s stdlib module. It provides a singleconfiguration point and makes use of SSLContext.load_default_certs().
• bpo-16203: Add re.fullmatch() function and regex.fullmatch() method, whichanchor the pattern at both ends of the string to match. Original patch byMatthew Barnett.
• bpo-13592: Improved the repr for regular expression pattern objects. Basedon patch by Hugo Lopes Tavares.
• bpo-19641: Added the audioop.byteswap() function to convert big-endiansamples to little-endian and vice versa.
• bpo-15204: Deprecated the ‘U’ mode in file-like objects.
• bpo-17810: Implement PEP 3154, pickle protocol 4.
• bpo-19668: Added support for the cp1125 encoding.
• bpo-19689: Add ssl.create_default_context() factory function. It creates anew SSLContext object with secure default settings.
• bpo-19727: os.utime(..., None) is now potentially more precise underWindows.
• bpo-17201: ZIP64 extensions now are enabled by default. Patch by WilliamMallard.
• bpo-19292: Add SSLContext.load_default_certs() to load default root CAcertificates from default stores or system stores. By default the methodloads CA certs for authentication of server certs.
• bpo-19673: Add pathlib to the stdlib as a provisional module (PEP 428).
• bpo-16596: pdb in a generator now properly skips over yield and yield fromrather than stepping out of the generator into its caller. (This isessential for stepping through asyncio coroutines.)
• bpo-17916: Added dis.Bytecode.from_traceback() anddis.Bytecode.current_offset to easily display “current instruction”markers in the new disassembly API (Patch by Claudiu Popa).
• bpo-19552: venv now supports bootstrapping pip into virtual environments
• bpo-17134: Finalize interface to Windows’ certificate store. Cert and CRLenumeration are now two functions. enum_certificates() also returnspurpose flags as set of OIDs.
• bpo-19555: Restore sysconfig.get_config_var(‘SO’), (and the distutilsequivalent) with a DeprecationWarning pointing people at $EXT_SUFFIX.
• bpo-8813: Add SSLContext.verify_flags to change the verification flags ofthe context in order to enable certification revocation list (CRL) checksor strict X509 rules.
• bpo-18294: Fix the zlib module to make it 64-bit safe.
• bpo-19682: Fix compatibility issue with old version of OpenSSL that wasintroduced byIssue #18379.
• bpo-14455: plistlib now supports binary plists and has an updated API.
• bpo-19633: Fixed writing not compressed 16- and 32-bit wave files onbig-endian platforms.
• bpo-18379: SSLSocket.getpeercert() returns CA issuer AIA fields, OCSP andCRL distribution points.
• bpo-18138: Implement cadata argument of SSLContext.load_verify_location()to load CA certificates and CRL from memory. It supports PEM and DERencoded strings.
• bpo-18775: Add name and block_size attribute to HMAC object. They nowprovide the same API elements as non-keyed cryptographic hash functions.
• bpo-17276: MD5 as default digestmod for HMAC is deprecated. The HMACmodule supports digestmod names, e.g. hmac.HMAC(‘sha1’).
• bpo-19449: in csv’s writerow, handle non-string keys when generating theerror message that certain keys are not in the ‘fieldnames’ list.
• bpo-13633: Added a new convert_charrefs keyword arg to HTMLParser that,when True, automatically converts all character references.
• bpo-2927: Added the unescape() function to the html module.
• bpo-8402: Added the escape() function to the glob module.
• bpo-17618: Add Base85 and Ascii85 encoding/decoding to the base64 module.
• bpo-19634: time.strftime(“%y”) now raises a ValueError on AIX when given ayear before 1900.
• Fix test.support.bind_port() to not cause an error when Python wascompiled on a system with SO_REUSEPORT defined in the headers but run on asystem with an OS kernel that does not support that reasonably new socketoption.
• Fix compilation error under gcc of the ctypes module bundled libffi forarm.
• bpo-19448: Add private API to SSL module to lookup ASN.1 objects by OID,NID, short name and long name.
• bpo-19282: dbm.open now supports the context management protocol. (Initalpatch by Claudiu Popa)
• bpo-8311: Added support for writing any bytes-like objects in the aifc,sunau, and wave modules.
• bpo-5202: Added support for unseekable files in the wave module.
• bpo-19544: Restore global option to ignore ~/.pydistutils.cfg inDistutils, accidentally removed in backout of distutils2 changes. (Seealso: bpo-1180)
• bpo-19523: Closed FileHandler leak which occurred when delay was set.
• bpo-19544: Restore support for –user and –group parameters to sdistcommand accidentally rolled back as part of the distutils2 rollback. (Seealso: bpo-6516)
• bpo-13674: Prevented time.strftime from crashing on Windows when given ayear before 1900 and a format of %y.
• bpo-19406: implementation of the ensurepip module (part of PEP 453). Patchby Donald Stufft and Nick Coghlan.
• bpo-19544: Restore use of urllib over http allowing use of http_proxy forDistutils upload command, a feature accidentally lost in the rollback ofdistutils2. (See also: bpo-6286)
• bpo-19544: Restore the read_pkg_file method todistutils.dist.DistributionMetadata accidentally removed in the undo ofdistutils2. (See also: bpo-7457)
• bpo-16685: Added support for any bytes-like objects in the audioop module.Removed support for strings.
• bpo-7171: Add Windows implementation ofinet_ntop andinet_pton tosocket module. Patch by Atsuo Ishimoto.
• bpo-19261: Added support for writing 24-bit samples in the sunau module.
• bpo-1097797: Added CP273 encoding, used on IBM mainframes in Germany andAustria. Mapping provided by Michael Bierenfeld.
• bpo-1575020: Fixed support of 24-bit wave files on big-endian platforms.
• bpo-19378: Fixed a number of cases in the dis module where the new “file”parameter was not being honoured correctly
• bpo-19378: Removed the “dis.Bytecode.show_info” method
• bpo-19378: Renamed the “dis.Bytecode.display_code” method to“dis.Bytecode.dis” and converted it to returning a string rather thanprinting output.
• bpo-19378: the “line_offset” parameter in the new “dis.get_instructions”API has been renamed to “first_line” (and the default value and usagechanged accordingly). This should reduce confusion with the more commonuse of “offset” in the dis docs to refer to bytecode offsets.
• bpo-18678: Corrected spwd struct member names in spwd module:sp_nam->sp_namp, and sp_pwd->sp_pwdp. The old names are kept as extrastructseq members, for backward compatibility.
• bpo-6157: Fixed tkinter.Text.debug(). tkinter.Text.bbox() now raisesTypeError instead of TclError on wrong number of arguments. Originalpatch by Guilherme Polo.
• bpo-10197: Rework subprocess.get[status]output to use subprocessfunctionality and thus to work on Windows. Patch by Nick Coghlan
• bpo-6160: The bbox() method of tkinter.Spinbox now returns a tuple ofintegers instead of a string. Based on patch by Guilherme Polo.
• bpo-19403: contextlib.redirect_stdout is now reentrant
• bpo-19286: Directories inpackage_data are no longer added to thefilelist, preventing failure outlined in the ticket.
• bpo-19480: HTMLParser now accepts all valid start-tag names as defined bythe HTML5 standard.
• bpo-15114: The html.parser module now raises a DeprecationWarning when thestrict argument of HTMLParser or the HTMLParser.error method are used.
• bpo-19410: Undo the special-casing removal of ‘’ forimportlib.machinery.FileFinder.
• bpo-19424: Fix the warnings module to accept filename containing surrogatecharacters.
• bpo-19435: Fix directory traversal attack on CGIHttpRequestHandler.
• bpo-19227: Remove pthread_atfork() handler. The handler was added to solve#18747 but has caused issues.
• bpo-19420: Fix reference leak in module initalization code of_hashopenssl.c
• bpo-19329: Optimized compiling charsets in regular expressions.
• bpo-19227: Try to fix deadlocks caused by re-seeding then OpenSSLpseudo-random number generator on fork().
• bpo-16037: HTTPMessage.readheaders() raises an HTTPException when morethan 100 headers are read. Adapted from patch by Jyrki Pulliainen.
• bpo-16040: CVE-2013-1752: nntplib: Limit maximum line lengths to 2048 toprevent readline() calls from consuming too much memory. Patch by JyrkiPulliainen.
• bpo-16041: CVE-2013-1752: poplib: Limit maximum line lengths to 2048 toprevent readline() calls from consuming too much memory. Patch by JyrkiPulliainen.
• bpo-17997: Change behavior ofssl.match_hostname() to follow RFC 6125,for security reasons. It now doesn’t match multiple wildcards norwildcards inside IDN fragments.
• bpo-16039: CVE-2013-1752: Change use of readline in imaplib module tolimit line length. Patch by Emil Lind.
• bpo-19330: the unnecessary wrapper functions have been removed from theimplementations of the new contextlib.redirect_stdout andcontextlib.suppress context managers, which also ensures they providereasonable help() output on instances
• bpo-19393: Fix symtable.symtable function to not be confused when thereare functions or classes named “top”.
• bpo-18685: Restore re performance to pre-PEP 393 levels.
• bpo-19339: telnetlib module is now using time.monotonic() when availableto compute timeout.
• bpo-19399: fix sporadic test_subprocess failure.
• bpo-13234: Fix os.listdir to work with extended paths on Windows. Patch bySantoso Wijaya.
• bpo-19375: The site module adding a “site-python” directory to sys.path,if it exists, is now deprecated.
• bpo-19379: Lazily import linecache in the warnings module, to make startupwith warnings faster until a warning gets printed.
• bpo-19288: Fixed the “in” operator of dbm.gnu databases for stringargument. Original patch by Arfrever Frehtes Taifersar Arahesis.
• bpo-19287: Fixed the “in” operator of dbm.ndbm databases for stringargument. Original patch by Arfrever Frehtes Taifersar Arahesis.
• bpo-19327: Fixed the working of regular expressions with too big charset.
• bpo-17400: New ‘is_global’ attribute for ipaddress to tell if an addressis allocated by IANA for global or private networks.
• bpo-19350: Increasing the test coverage of macurl2path. Patch by ColinWilliams.
• bpo-19365: Optimized the parsing of long replacement string in re.sub*()functions.
• bpo-19352: Fix unittest discovery when a module can be reached throughseveral paths (e.g. under Debian/Ubuntu with virtualenv).
• bpo-15207: Fix mimetypes to read from correct part of Windows registryOriginal patch by Dave Chambers
• bpo-16595: Add prlimit() to resource module.
• bpo-19324: Expose Linux-specific constants in resource module.
• Load SSL’s error strings in hashlib.
• bpo-18527: Upgrade internal copy of zlib to 1.2.8.
• bpo-19274: Add a filterfunc parameter to PyZipFile.writepy.
• bpo-8964: fix platform._sys_version to handle IronPython 2.6+. Patch byMartin Matusiak.
• bpo-19413: Restore pre-3.3 reload() semantics of re-finding modules.
• bpo-18958: Improve error message for json.load(s) while passing a stringthat starts with a UTF-8 BOM.
• bpo-19307: Improve error message for json.load(s) while passing objects ofthe wrong type.
• bpo-16038: CVE-2013-1752: ftplib: Limit amount of data read by limitingthe call to readline(). Original patch by Michał Jastrzębski andGiampaolo Rodola.
• bpo-17087: Improved the repr for regular expression match objects.

Tests¶

• bpo-19664: test_userdict’s repr test no longer depends on the order ofdict elements.
• bpo-19440: Clean up test_capi by removing an unnecessary __future__import, converting from test_main to unittest.main, and running the_testcapi module tests as subTests of a unittest TestCase method.
• bpo-19378: the main dis module tests are now run with both stdoutredirectionand passing an explicit file parameter
• bpo-19378: removed the not-actually-helpful assertInstructionMatches andassertBytecodeExactlyMatches helpers from bytecode_helper
• bpo-18702: All skipped tests now reported as skipped.
• bpo-19439: interpreter embedding tests are now executed on Windows (Patchby Zachary Ware)
• bpo-19085: Added basic tests for all tkinter widget options.
• bpo-19384: Fix test_py_compile for root user, patch by Claudiu Popa.

Documentation¶

• bpo-18326: Clarify that list.sort’s arguments are keyword-only. Also,attempt to reduce confusion in the glossary by not saying there aredifferent “types” of arguments and parameters.

Build¶

• bpo-19358: “make clinic” now runs the Argument Clinic preprocessor overall CPython source files.
• Update SQLite to 3.8.1, xz to 5.0.5, and Tcl/Tk to 8.6.1 on Windows.
• bpo-16632: Enable DEP and ASLR on Windows.
• bpo-17791: Drop PREFIX and EXEC_PREFIX definitions from PC/pyconfig.h
• Add workaround for VS 2010 nmake clean issue. VS 2010 doesn’t set up PATHfor nmake.exe correctly.
• bpo-19550: Implement Windows installer changes of PEP 453 (ensurepip).
• bpo-19520: Fix compiler warning in the _sha3 module on 32bit Windows.
• bpo-19356: Avoid using a C variabled named “_self”, it’s a reserved wordin some C compilers.
• bpo-15792: Correct build options on Win64. Patch by Jeremy Kloth.
• bpo-19373: Apply upstream change to Tk 8.5.15 fixing OS X 10.9 screenrefresh problem for OS X installer build.
• bpo-19649: On OS X, the same set of file names are now installed in bindirectories for all configurations: non-framework vs framework, and singlearch vs universal builds. pythonx.y-32 is now always installed for64-bit/32-bit universal builds. The obsolete and undocumented pythonw*symlinks are no longer installed anywhere.
• bpo-19553: PEP 453 - “make install” and “make altinstall” now install orupgrade pip by default, using the bundled pip provided by the newensurepip module. A new configure option,–with-ensurepip[=upgrade|install|no], is available to override thedefault ensurepip “–upgrade” option. The option can also be set with“make [alt]install ENSUREPIP=[upgrade|install|no]”.
• bpo-19551: PEP 453 - the OS X installer now installs pip by default.
• Update third-party libraries for OS X installers: xz 5.0.3 -> 5.0.5,SQLite 3.7.13 -> 3.8.1
• bpo-15663: Revert OS X installer built-in Tcl/Tk support for 3.4.0b1. Somethird-party projects, such as Matplotlib and PIL/Pillow, depended on beingable to build with Tcl and Tk frameworks in /Library/Frameworks.

Tools/Demos¶

• bpo-19730: Argument Clinic now supports all the existing PyArg “formatunits” as legacy converters, as well as two new features: “selfconverters” and the “version” directive.
• bpo-19552: pyvenv now bootstraps pip into virtual environments by default(pass –without-pip to request the old behaviour)
• bpo-19390: Argument Clinic no longer accepts malformed Python and C ids.

Core and Builtins¶

• bpo-19301: Give classes and functions that are explicitly marked global aglobal qualname.
• bpo-19279: UTF-7 decoder no longer produces illegal strings.
• bpo-16612: Add “Argument Clinic”, a compile-time preprocessor for C filesto generate argument parsing code. (See PEP 436.)
• bpo-18810: Shift stat calls in importlib.machinery.FileFinder such thatthe code is optimistic that if something exists in a directory namedexactly like the possible package being searched for that it’s inactuality a directory.
• bpo-18416: importlib.machinery.PathFinder now treats ‘’ as the cwd andimportlib.machinery.FileFinder no longer special-cases ‘’ to ‘.’. Thisleads to modules imported from cwd to now possess an absolute file pathfor __file__ (this does not affect modules specified by path on the CLIbut it does affect -m/runpy). It also allows FileFinder to be moreconsistent by not having an edge case.
• bpo-4555: All exported C symbols are now prefixed with either “Py” or“_Py”.
• bpo-19219: Speed up marshal.loads(), and make pyc files slightly (5% to10%) smaller.
• bpo-19221: Upgrade Unicode database to version 6.3.0.
• bpo-16742: The result of the C callback PyOS_ReadlineFunctionPointer mustnow be a string allocated by PyMem_RawMalloc() or PyMem_RawRealloc() (orNULL if an error occurred), instead of a string allocated byPyMem_Malloc() or PyMem_Realloc().
• bpo-19199: RemovePyThreadState.tick_counter field
• Fix macro expansion of _PyErr_OCCURRED(), and make sure to use it in atleast one place so as to avoid regressions.
• bpo-19087: Improve bytearray allocation in order to allow cheap popping ofdata at the front (slice deletion).
• bpo-19014: memoryview.cast() is now allowed on zero-length views.
• bpo-18690: memoryview is now automatically registered withcollections.abc.Sequence
• bpo-19078: memoryview now correctly supports the reversed builtin (Patchby Claudiu Popa)

Library¶

• bpo-17457: unittest test discovery now works with namespace packages.Patch by Claudiu Popa.
• bpo-18235: Fix the sysconfig variables LDSHARED and BLDSHARED under AIX.Patch by David Edelsohn.
• bpo-18606: Add the new “statistics” module (PEP 450). Contributed bySteven D’Aprano.
• bpo-12866: The audioop module now supports 24-bit samples.
• bpo-19254: Provide an optimized Python implementation of pbkdf2_hmac.
• bpo-19201: Add “x” mode (exclusive creation) in opening file to bz2, gzipand lzma modules. Patches by Tim Heaney and Vajrasky Kok. (See also:bpo-19222, bpo-19223)
• Fix a reference count leak in _sre.
• bpo-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 withthe code. This module will haveprovisional status in Python 3.4.
• bpo-19276: Fixed the wave module on 64-bit big-endian platforms.
• bpo-19266: Rename the new-in-3.4contextlib.ignore context manager tocontextlib.suppress in order to be more consistent with existingdescriptions of that operation elsewhere in the language and standardlibrary documentation (Patch by Zero Piraeus).
• bpo-18891: Completed the new email package (provisional) API additions byadding new classes EmailMessage, MIMEPart, and ContentManager.
• bpo-18281: Unused stat constants removed fromtarfile.
• bpo-18999: Multiprocessing now supports ‘contexts’ with the same API asthe module, but bound to specified start methods.
• bpo-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 bytesobject.
• bpo-18725: The textwrap module now supports truncating multiline text.
• bpo-18776: atexit callbacks now display their full traceback when theyraise an exception.
• bpo-17827: Add the missing documentation forcodecs.encode andcodecs.decode.
• bpo-19218: Rename collections.abc to _collections_abc in order to speed upinterpreter start.
• bpo-18582: Add ‘pbkdf2_hmac’ to the hashlib module. It implements PKCS#5password-based key derivation functions with HMAC as pseudorandomfunction.
• bpo-19131: The aifc module now correctly reads and writes sampwidth ofcompressed streams.
• bpo-19209: Remove import of copyreg from the os module to speed upinterpreter startup. stat_result and statvfs_result are now hard-coded toreside in the os module.
• bpo-19205: Don’t import the ‘re’ module in site and sysconfig module tospeed up interpreter start.
• bpo-9548: Add a minimal “_bootlocale” module that is imported by the _iomodule instead of the full locale module.
• bpo-18764: Remove the ‘print’ alias for the PDB ‘p’ command so that it nolonger shadows the print function.
• bpo-19158: A rare race in BoundedSemaphore could allow .release() toooften.
• bpo-15805: Add contextlib.redirect_stdout().
• bpo-18716: Deprecate the formatter module.
• bpo-10712: 2to3 has a new “asserts” fixer that replaces deprecated namesof unittest methods (e.g. failUnlessEqual -> assertEqual).
• bpo-18037: 2to3 now escapes'\u' and'\U' in native strings.
• bpo-17839: base64.decodebytes and base64.encodebytes now accept any objectthat exports a 1 dimensional array of bytes (this means the same is nowalso true for base64_codec)
• bpo-19132: The pprint module now supports compact mode.
• bpo-19137: The pprint module now correctly formats instances of set andfrozenset subclasses.
• bpo-10042: functools.total_ordering now correctly handles NotImplementedbeing returned by the underlying comparison function (Patch by KatieMiller)
• bpo-19092: contextlib.ExitStack now correctly reraises exceptions from the__exit__ callbacks of inner context managers (Patch by Hrvoje Nikšić)
• bpo-12641: Avoid passing “-mno-cygwin” to the mingw32 compiler, exceptwhen necessary. Patch by Oscar Benjamin.
• bpo-5845: In site.py, only load readline history from ~/.python_history ifno history has been read already. This avoids double writes to thehistory file at shutdown.
• Properly initialize all fields of a SSL object after allocation.
• bpo-19095: SSLSocket.getpeercert() now raises ValueError when the SSLhandshake hasn’t been done.
• bpo-4366: Fix building extensions on all platforms when –enable-shared isused.
• bpo-19030: Fixedinspect.getmembers andinspect.classify_class_attrsto attempt activating descriptors before falling back to a __dict__ searchfor faulty descriptors.inspect.classify_class_attrs no longer returnsAttributes whose home class is None.

C API¶

• bpo-1772673: The type ofchar* arguments now changed toconstchar*.
• bpo-16129: Added aPy_SetStandardStreamEncoding pre-initialization APIto allow embedding applications like Blender to force a particularencoding and error handler for the standard IO streams (initial patch byBastien Montagne)

Tests¶

• bpo-19275: Fix test_site on AMD64 Snow Leopard
• bpo-14407: Fix unittest test discovery in test_concurrent_futures.
• bpo-18919: Unified and extended tests for audio modules: aifc, sunau andwave.
• bpo-18714: Added tests forpdb.find_function().

Documentation¶

• bpo-18758: Fixed and improved cross-references.
• bpo-18972: Modernize email examples and use the argparse module in them.

Build¶

• bpo-19130: Correct PCbuild/readme.txt, Python 3.3 and 3.4 require VS 2010.
• bpo-15663: Update OS X 10.6+ installer to use Tcl/Tk 8.5.15.
• bpo-14499: Fix several problems with OS X universal build support: 1.ppc arch detection for extension module builds broke with Xcode 5 2. ppcarch detection in configure did not work on OS X 10.4 3. -sysroot and-arch flags were unnecessarily duplicated 4. there was no obvious way toconfigure an intel-32 only build.
• bpo-19019: Change the OS X installer build script to use CFLAGS instead ofOPT for special build options. By setting OPT, some compiler-specificoptions like -fwrapv were overridden and thus not used, which could resultin broken interpreters when building with clang.

Core and Builtins¶

• bpo-18818: The “encodingname” part of PYTHONIOENCODING is now optional.
• bpo-19098: Prevent overflow in the compiler when the recursion limit isset absurdly high.

Library¶

• bpo-18929:inspect.classify_class_attrs() now correctly finds classattributes returned bydir() that are located in the metaclass.
• bpo-18950: Fix miscellaneous bugs in the sunau module.Au_read.readframes() now updates current file position and reads correctnumber of frames from multichannel stream. Au_write.writeframesraw() nowcorrectly updates current file position. Au_read.getnframes() now returnsan integer (as in Python 2). Au_read and Au_write now correctly works withfile object if start file position is not a zero.
• bpo-18594: The fast path for collections.Counter() was never taken due toan over- restrictive type check.
• bpo-19053: ZipExtFile.read1() with non-zero argument no more returns emptybytes until end of data.
• logging: added support for Unix domain sockets to SocketHandler andDatagramHandler.
• bpo-18996: TestCase.assertEqual() now more cleverly shorten differingstrings in error report.
• bpo-19034: repr() for tkinter.Tcl_Obj now exposes string reperesentation.
• bpo-18978:urllib.request.Request now allows the method to beindicated on the class and no longer sets it to None in__init__.
• bpo-18626: the inspect module now offers a basic command lineintrospection interface (Initial patch by Claudiu Popa)
• bpo-3015: Fixed tkinter with wantobject=False. Any Tcl command callreturned empty string.
• bpo-19037: The mailbox module now makes all changes to maildir filesbefore moving them into place, to avoid race conditions with otherprograms that may be accessing the maildir directory.
• bpo-14984: On POSIX systems, when netrc is called without a filenameargument (and therefore is reading the user’s $HOME/.netrc file), it nowenforces the same security rules as typical ftp clients: the .netrc filemust be owned by the user that owns the process and must not be readableby any other user.
• bpo-18873: The tokenize module now detects Python source code encodingonly in comment lines.
• bpo-17764: Enable http.server to bind to a user specified networkinterface. Patch contributed by Malte Swart.
• bpo-18937: Add an assertLogs() context manager to unittest.TestCase toensure that a block of code emits a message using the logging module.
• bpo-17324: Fix http.server’s request handling case on trailing ‘/’. Patchcontributed by Vajrasky Kok.
• bpo-19018: The heapq.merge() function no longer suppresses IndexError inthe underlying iterables.
• bpo-18784: The uuid module no longer attempts to load libc via ctypes.CDLLif all the necessary functions have already been found in libuuid. Patchby Evgeny Sologubov.
• ThePYTHONFAULTHANDLER environment variable now only enables thefaulthandler module if the variable is non-empty. Same behaviour thanother variables likePYTHONDONTWRITEBYTECODE.
• bpo-1565525: New functiontraceback.clear_frames will clear the localvariables of all the stack frames referenced by a traceback object.

Tests¶

• bpo-18952: Fix regression in support data downloads introduced whentest.support was converted to a package. Regression noticed by ZacharyWare.

IDLE¶

• bpo-18873: IDLE now detects Python source code encoding only in commentlines.
• bpo-18988: The “Tab” key now works when a word is already autocompleted.

Documentation¶

• bpo-17003: Unified the size argument names in the io module with commonpractice.

Build¶

• bpo-18596: Support the use of address sanity checking in recent versionsof clang and GCC by appropriately marking known false alarms in the smallobject allocator. Patch contributed by Dhiru Kholia.

Tools/Demos¶

• bpo-18873: 2to3 and the findnocoding.py script now detect Python sourcecode encoding only in comment lines.

Core and Builtins¶

• bpo-18942: sys._debugmallocstats() output was damaged on Windows.
• bpo-18571: Implementation of the PEP 446: file descriptors and filehandles are now created non-inheritable; add functionsos.get/set_inheritable(), os.get/set_handle_inheritable() andsocket.socket.get/set_inheritable().
• bpo-11619: The parser and the import machinery do not encode Unicodefilenames anymore on Windows.
• bpo-18808: Non-daemon threads are now automatically joined when asub-interpreter is shutdown (it would previously dump a fatal error).
• Remove support for compiling on systems without getcwd().
• bpo-18774: Remove last bits of GNU PTH thread code and thread_pth.h.
• bpo-18771: Add optimization to set object lookups to reduce the cost ofhash collisions. The core idea is to inspect a second key/hash pair foreach cache line retrieved.
• bpo-16105: When a signal handler fails to write to the file descriptorregistered withsignal.set_wakeup_fd(), report an exception instead ofignoring the error.
• bpo-18722: Remove uses of the “register” keyword in C code.
• bpo-18667: Add missing “HAVE_FCHOWNAT” symbol to posix._have_functions.
• bpo-16499: Add command line option for isolated mode.
• bpo-15301: Parsing fd, uid, and gid parameters for builtins inModules/posixmodule.c is now far more robust.
• bpo-18368: PyOS_StdioReadline() no longer leaks memory when realloc()fail.
• bpo-17934: Add a clear() method to frame objects, to help clean upexpensive details (local variables) and break reference cycles.
• bpo-18780: %-formatting codes %d, %i, and %u now treat int-subclasses asint (displays value of int-subclass instead of str(int-subclass) ).

Library¶

• bpo-18808: Thread.join() now waits for the underlying thread state to bedestroyed before returning. This prevents unpredictable aborts inPy_EndInterpreter() when some non-daemon threads are still running.
• bpo-18458: Prevent crashes with newer versions of libedit. Its readlineemulation has changed from 0-based indexing to 1-based like gnu readline.
• bpo-18852: Handle case ofreadline.__doc__ beingNone in the newreadline activation code insite.py.
• bpo-18672: Fixed format specifiers for Py_ssize_t in debugging output inthe _sre module.
• bpo-18830: inspect.getclasstree() no longer produces duplicate entrieseven when input list contains duplicates.
• bpo-18878: sunau.open now supports the context management protocol. Basedon patches by Claudiu Popa and R. David Murray.
• bpo-18909: Fix _tkinter.tkapp.interpaddr() on Windows 64-bit, don’t cast64-bit pointer to long (32 bits).
• bpo-18876: The FileIO.mode attribute now better reflects the actual modeunder which the file was opened. Patch by Erik Bray.
• bpo-16853: Add new selectors module.
• bpo-18882: Add threading.main_thread() function.
• bpo-18901: The sunau getparams method now returns a namedtuple rather thana plain tuple. Patch by Claudiu Popa.
• bpo-17487: The result of the wave getparams method now is pickleableagain. Patch by Claudiu Popa.
• bpo-18756: os.urandom() now uses a lazily-opened persistent filedescriptor, so as to avoid using many file descriptors when run inparallel from multiple threads.
• bpo-18418: After fork(), reinit all threads states, not only active ones.Patch by A. Jesse Jiryu Davis.
• bpo-17974: Switch unittest from using getopt to using argparse.
• bpo-11798: TestSuite now drops references to own tests after execution.
• bpo-16611: http.cookie now correctly parses the ‘secure’ and ‘httponly’cookie flags.
• bpo-11973: Fix a problem in kevent. The flags and fflags fields are nowproperly handled as unsigned.
• bpo-18807:pyvenv now takes a –copies argument allowing copiesinstead of symlinks even where symlinks are available and the default.
• bpo-18538:python-mdis now uses argparse for argument processing.Patch by Michele Orrù.
• bpo-18394: Close cgi.FieldStorage’s optional file.
• bpo-17702: On error, os.environb now suppresses the exception context whenraising a new KeyError with the original key.
• bpo-16809: Fixed some tkinter incompabilities with Tcl/Tk 8.6.
• bpo-16809: Tkinter’s splitlist() and split() methods now accept Tcl_Objargument.
• bpo-18324: set_payload now correctly handles binary input. This alsosupersedes the previous fixes for #14360, #1717, and #16564.
• bpo-18794: Add a fileno() method and a closed attribute to select.devpollobjects.
• bpo-17119: Fixed integer overflows when processing large strings andtuples in the tkinter module.
• bpo-18747: Re-seed OpenSSL’s pseudo-random number generator after fork. Apthread_atfork() parent handler is used to seed the PRNG with pid, timeand some stack data.
• bpo-8865: Concurrent invocation of select.poll.poll() now raises aRuntimeError exception. Patch by Christian Schubert.
• bpo-18777: The ssl module now uses the new CRYPTO_THREADID API of OpenSSL1.0.0+ instead of the deprecated CRYPTO id callback function.
• bpo-18768: Correct doc string of RAND_edg(). Patch by Vajrasky Kok.
• bpo-18178: Fix ctypes on BSD. dlmalloc.c was compiled twice which brokemalloc weak symbols.
• bpo-18709: Fix CVE-2013-4238. The SSL module now handles NULL bytes insidesubjectAltName correctly. Formerly the module has used OpenSSL’sGENERAL_NAME_print() function to get the string represention of ASN.1strings forrfc822Name (email),dNSName (DNS) anduniformResourceIdentifier (URI).
• bpo-18701: Remove support of old CPython versions (<3.0) from C code.
• bpo-18756: Improve error reporting in os.urandom() when the failure is dueto something else than /dev/urandom not existing (for example, exhaustingthe file descriptor limit).
• bpo-18673: Add O_TMPFILE to os module. O_TMPFILE requires Linux kernel3.11 or newer. It’s only defined on system with 3.11 uapi headers, too.
• bpo-18532: Change the builtin hash algorithms’ names to lower case namesas promised by hashlib’s documentation.
• bpo-8713: add new spwan and forkserver start methods, and new functionsget_all_start_methods, get_start_method, and set_start_method, tomultiprocessing.
• bpo-18405: Improve the entropy of crypt.mksalt().
• bpo-12015: The tempfile module now uses a suffix of 8 random charactersinstead of 6, to reduce the risk of filename collision. The entropy wasreduced when uppercase letters were removed from the charset used togenerate random characters.
• bpo-18585: Addtextwrap.shorten() to collapse and truncate a pieceof text to a given length.
• bpo-18598: Tweak exception message for importlib.import_module() toinclude the module name when a key argument is missing.
• bpo-19151: Fix docstring and use of _get_supported_file_loaders() toreflect 2-tuples.
• bpo-19152: Add ExtensionFileLoader.get_filename().
• bpo-18676: Change ‘positive’ to ‘non-negative’ in queue.py put and getdocstrings and ValueError messages. Patch by Zhongyue Luo
• Fix refcounting issue with extension types in tkinter.
• bpo-8112: xlmrpc.server’s DocXMLRPCServer server no longer raises an errorif methods have annotations; it now correctly displays the annotations.
• bpo-18600: Added policy argument to email.message.Message.as_string, andas_bytes and __bytes__ methods to Message.
• bpo-18671: Output more information when logging exceptions occur.
• bpo-18621: Prevent the site module’s patched builtins from keeping toomany references alive for too long.
• bpo-4885: Add weakref support to mmap objects. Patch by Valerie Lambert.
• bpo-8860: Fixed rounding in timedelta constructor.
• bpo-18849: Fixed a Windows-specific tempfile bug where collision with anexisting directory caused mkstemp and related APIs to fail instead ofretrying. Report and fix by Vlad Shcherbina.
• bpo-18920: argparse’s default destination for the version action (-v,–version) has also been changed to stdout, to match the Pythonexecutable.

Tests¶

• bpo-18623: Factor out the _SuppressCoreFiles context manager intotest.support. Patch by Valerie Lambert.
• bpo-12037: Fix test_email for desktop Windows.
• bpo-15507: test_subprocess’s test_send_signal could fail if the testrunner were run in an environment where the process inherited an ignoresetting for SIGINT. Restore the SIGINT handler to the desiredKeyboardInterrupt raising one during that test.
• bpo-16799: Switched from getopt to argparse style in regrtest’s argumentparsing. Added more tests for regrtest’s argument parsing.
• bpo-18792: Use “127.0.0.1” or ”::1” instead of “localhost” as much aspossible, since “localhost” goes through a DNS lookup under recent Windowsversions.

IDLE¶

• bpo-18489: Add tests for SearchEngine. Original patch by Phil Webster.

Documentation¶

• bpo-18743: Fix references to non-existant “StringIO” module.
• bpo-18783: Removed existing mentions of Python long type in docstrings,error messages and comments.

Build¶

• bpo-1584: Provide configure options to override default search paths forTcl and Tk when building _tkinter.
• bpo-15663: Tcl/Tk 8.5.14 is now included with the OS X 10.6+ 64-/32-bitinstaller. It is no longer necessary to install a third-party version ofTcl/Tk 8.5 to work around the problems in the Apple-supplied Tcl/Tk 8.5shipped in OS X 10.6 and later releases.

Tools/Demos¶

• bpo-18922: Now The Lib/smtpd.py and Tools/i18n/msgfmt.py scripts writetheir version strings to stdout, and not to sderr.

Core and Builtins¶

• bpo-16741: Fix an error reporting in int().
• bpo-17899: Fix rare file descriptor leak in os.listdir().
• bpo-10241: Clear extension module dict copies at interpreter shutdown.Patch by Neil Schemenauer, minimally modified.
• bpo-9035: ismount now recognises volumes mounted below a drive root onWindows. Original patch by Atsuo Ishimoto.
• bpo-18214: Improve finalization of Python modules to avoid setting theirglobals to None, in most cases.
• bpo-18112: PEP 442 implementation (safe object finalization).
• bpo-18552: Check return value of PyArena_AddPyObject() inobj2ast_object().
• bpo-18560: Fix potential NULL pointer dereference in sum().
• bpo-18520: Add a new PyStructSequence_InitType2() function, same thanPyStructSequence_InitType() except that it has a return value (0 onsuccess, -1 on error).
• bpo-15905: Fix theoretical buffer overflow in handling of sys.argv[0],prefix and exec_prefix if the operation system does not obey MAXPATHLEN.
• bpo-18408: Fix many various bugs in code handling errors, especially onmemory allocation failure (MemoryError).
• bpo-18344: Fix potential ref-leaks in _bufferedreader_read_all().
• bpo-18342: Use the repr of a module name when an import fails when usingfrom...import....
• bpo-17872: Fix a segfault in marshal.load() when input stream returns morebytes than requested.
• bpo-18338:python--version now prints version string to stdout, and notto stderr. Patch by Berker Peksag and Michael Dickens.
• bpo-18426: Fix NULL pointer dereference in C extension import whenPyModule_GetDef() returns an error.
• bpo-17206: On Windows, increase the stack size from 2 MB to 4.2 MB to fixa stack overflow in the marshal module (fix a crash in test_marshal).Patch written by Jeremy Kloth.
• bpo-3329: Implement the PEP 445: Add new APIs to customize Python memoryallocators.
• bpo-18328: Reorder ops in PyThreadState_Delete*() functions. Now thetstate is first removed from TLS and then deallocated.
• bpo-13483: Use VirtualAlloc in obmalloc on Windows.
• bpo-18184: PyUnicode_FromFormat() and PyUnicode_FromFormatV() now raiseOverflowError when an argument of %c format is out of range.
• bpo-18111: The min() and max() functions now support a default argument tobe returned instead of raising a ValueError on an empty sequence.(Contributed by Julian Berman.)
• bpo-18137: Detect integer overflow on precision in float.__format__() andcomplex.__format__().
• bpo-18183: Fix various unicode operations on strings with large unicodecodepoints.
• bpo-18180: Fix ref leak in _PyImport_GetDynLoadWindows().
• bpo-18038: SyntaxError raised during compilation sources with illegalencoding now always contains an encoding name.
• bpo-17931: Resolve confusion on Windows between pids and process handles.
• Tweak the exception message when the magic number or size value in abytecode file is truncated.
• bpo-17932: Fix an integer overflow issue on Windows 64-bit in iterators:change the C type of seqiterobject.it_index from long to Py_ssize_t.
• bpo-18065: Don’t set __path__ to the package name for frozen packages.
• bpo-18088: When reloading a module, unconditionally reset all relevantattributes on the module (e.g. __name__, __loader__, __package__,__file__, __cached__).
• bpo-17937: Try harder to collect cyclic garbage at shutdown.
• bpo-12370: Prevent class bodies from interfering with the __class__closure.
• bpo-17644: Fix a crash in str.format when curly braces are used in squarebrackets.
• bpo-17237: Fix crash in the ASCII decoder on m68k.
• bpo-17927: Frame objects kept arguments alive if they had been copied intoa cell, even if the cell was cleared.
• bpo-1545463: At shutdown, defer finalization of codec modules so thatstderr remains usable.
• bpo-7330: Implement width and precision (ex: “%5.3s”) for the formatstring of PyUnicode_FromFormat() function, original patch written by YsjRay.
• bpo-1545463: Global variables caught in reference cycles are nowgarbage-collected at shutdown.
• bpo-17094: Clear stale thread states after fork(). Note that this is apotentially disruptive change since it may release some system resourceswhich would otherwise remain perpetually alive (e.g. database connectionskept in thread-local storage).
• bpo-17408: Avoid using an obsolete instance of the copyreg module when theinterpreter is shutdown and then started again.
• bpo-5845: Enable tab-completion in the interactive interpreter by default,thanks to a new sys.__interactivehook__.
• bpo-17115: Module initialization now includes setting __package__ and__loader__ attributes to None. (See also: bpo-17116)
• bpo-17853: Ensure locals of a class that shadow free variables always winover the closures.
• bpo-17863: In the interactive console, don’t loop forever if the encodingcan’t be fetched from stdin.
• bpo-17867: Raise an ImportError if __import__ is not found in__builtins__.
• bpo-18698: Ensure importlib.reload() returns the module out ofsys.modules.
• bpo-17857: Prevent build failures with pre-3.5.0 versions of sqlite3, suchas was shipped with Centos 5 and Mac OS X 10.4.
• bpo-17413: sys.settrace callbacks were being passed a string instead of anexception instance for the ‘value’ element of the arg tuple if theexception originated from C code; now an exception instance is alwaysprovided.
• bpo-17782: Fix undefined behaviour on platforms wherestructtimespec‘s “tv_nsec” member is not a C long.
• bpo-17722: When looking up __round__, resolve descriptors.
• bpo-16061: Speed up str.replace() for replacing 1-character strings.
• bpo-17715: Fix segmentation fault from raising an exception in a __trunc__method.
• bpo-17643: Add __callback__ attribute to weakref.ref.
• bpo-16447: Fixed potential segmentation fault when setting __name__ on aclass.
• bpo-17669: Fix crash involving finalization of generators using yieldfrom.
• bpo-14439: Python now prints the traceback on runpy failure at startup.
• bpo-17469: Fix _Py_GetAllocatedBlocks() and sys.getallocatedblocks() whenrunning on valgrind.
• bpo-17619: Make input() check for Ctrl-C correctly on Windows.
• bpo-17357: Add missing verbosity messages for -v/-vv that were lost duringthe importlib transition.
• bpo-17610: Don’t rely on non-standard behavior of the C qsort() function.
• bpo-17323: The “[X refs, Y blocks]” printed by debug builds has beendisabled by default. It can be re-enabled with the-Xshowrefcountoption.
• bpo-17328: Fix possible refleak in dict.setdefault.
• bpo-17275: Corrected class name in init error messages of the C version ofBufferedWriter and BufferedRandom.
• bpo-7963: Fixed misleading error message that issued when object is calledwithout arguments.
• bpo-8745: Small speed up zipimport on Windows. Patch by Catalin Iacob.
• bpo-5308: Raise ValueError when marshalling too large object (a sequencewith size >= 2**31), instead of producing illegal marshal data.
• bpo-12983: Bytes literals with invalid\x escape now raise aSyntaxError and a full traceback including line number.
• bpo-16967: In function definition, evaluate positional defaults beforekeyword-only defaults.
• bpo-17173: Remove uses of locale-dependent C functions (isalpha() etc.) inthe interpreter.
• bpo-17137: When an Unicode string is resized, the internal wide characterstring (wstr) format is now cleared.
• bpo-17043: The unicode-internal decoder no longer read past the end ofinput buffer.
• bpo-17098: All modules now have __loader__ set even if they pre-exist thebootstrapping of importlib.
• bpo-16979: Fix error handling bugs in the unicode-escape-decode decoder.
• bpo-16772: The base argument to the int constructor no longer acceptsfloats, or other non-integer objects with an __int__ method. Objects withan __index__ method are now accepted.
• bpo-10156: In the interpreter’s initialization phase, unicode globals arenow initialized dynamically as needed.
• bpo-16980: Fix processing of escaped non-ascii bytes in theunicode-escape-decode decoder.
• bpo-16975: Fix error handling bug in the escape-decode bytes decoder.
• bpo-14850: Now a charmap decoder treats U+FFFE as “undefined mapping” inany mapping, not only in a string.
• bpo-16613: Addm argument tocollections.Chainmap.new_child to allowthe new child map to be specified explicitly.
• bpo-16730: importlib.machinery.FileFinder now no longers raises anexception when trying to populate its cache and it finds out the directoryis unreadable or has turned into a file. Reported and diagnosed by DavidPritchard.
• bpo-16906: Fix a logic error that prevented most static strings from beingcleared.
• bpo-11461: Fix the incremental UTF-16 decoder. Original patch by AmauryForgeot d’Arc.
• bpo-16856: Fix a segmentation fault from calling repr() on a dict with akey whose repr raise an exception.
• bpo-16367: Fix FileIO.readall() on Windows for files larger than 2 GB.
• bpo-16761: Calling int() with base argument only now raises TypeError.
• bpo-16759: Support the full DWORD (unsigned long) range in Reg2Py whenretrieving a REG_DWORD value. This corrects functions likewinreg.QueryValueEx that may have been returning truncated values.
• bpo-14420: Support the full DWORD (unsigned long) range in Py2Reg whenpassed a REG_DWORD value. Fixes OverflowError in winreg.SetValueEx.
• bpo-11939: Set the st_dev attribute of stat_result to allow Windows totake advantage of the os.path.samefile/sameopenfile/samestatimplementations used by other platforms.
• bpo-16772: The int() constructor’s second argument (base) no longeraccepts non integer values. Consistent with the behavior in Python 2.
• bpo-14470: Remove w9xpopen support per PEP 11.
• bpo-9856: Replace deprecation warning with raising TypeError inobject.__format__. Patch by Florent Xicluna.
• bpo-16597: In buffered and text IO, call close() on the underlying streamif invoking flush() fails.
• bpo-16722: In the bytes() constructor, try to call __bytes__ on theargument before __index__.
• bpo-16421: loading multiple modules from one shared object is now handledcorrectly (previously, the first module loaded from that file was silentlyreturned). Patch by Václav Šmilauer.
• bpo-16602: When a weakref’s target was part of a long deallocation chain,the object could remain reachable through its weakref even though itsrefcount had dropped to zero.
• bpo-16495: Remove extraneous NULL encoding check from bytes_decode().
• bpo-16619: Create NameConstant AST class to represent None, True, andFalse literals. As a result, these constants are never loaded at runtimefrom builtins.
• bpo-16455: On FreeBSD and Solaris, if the locale is C, theASCII/surrogateescape codec is now used (instead of the locale encoding)to decode the command line arguments. This change fixes inconsistencieswith os.fsencode() and os.fsdecode(), because these operating systemsannounce an ASCII locale encoding, but actually use the ISO-8859-1encoding in practice.
• bpo-16562: Optimize dict equality testing. Patch by Serhiy Storchaka.
• bpo-16588: Silence unused-but-set warnings in Python/thread_pthread
• bpo-16592: stringlib_bytes_join doesn’t raise MemoryError on allocationfailure.
• bpo-16546: Fix: ast.YieldFrom argument is now mandatory.
• bpo-16514: Fix regression causing a traceback when sys.path[0] is None(actually, any non-string or non-bytes type).
• bpo-16306: Fix multiple error messages when unknown command lineparameters where passed to the interpreter. Patch by Hieu Nguyen.
• bpo-16215: Fix potential double memory free in str.replace(). Patch bySerhiy Storchaka.
• bpo-16290: A float return value from the __complex__ special method is nolonger accepted in the complex() constructor.
• bpo-16416: On Mac OS X, operating system data are now alwaysencoded/decoded to/from UTF-8/surrogateescape, instead of the localeencoding (which may be ASCII if no locale environment variable is set), toavoid inconsistencies with os.fsencode() and os.fsdecode() functions whichare already using UTF-8/surrogateescape.
• bpo-16453: Fix equality testing of dead weakref objects.
• bpo-9535: Fix pending signals that have been received but not yet handledby Python to not persist after os.fork() in the child process.
• bpo-14794: Fix slice.indices to return correct results for huge values,rather than raising OverflowError.
• bpo-15001: fix segfault on “del sys.modules[‘__main__’]”. Patch by VictorStinner.
• bpo-8271: the utf-8 decoder now outputs the correct number of U+FFFDcharacters when used with the ‘replace’ error handler on invalid utf-8sequences. Patch by Serhiy Storchaka, tests by Ezio Melotti.
• bpo-5765: Apply a hard recursion limit in the compiler instead of blowingthe stack and segfaulting. Initial patch by Andrea Griffini.
• bpo-16402: When slicing a range, fix shadowing of exceptions from__index__.
• bpo-16336: fix input checking in the surrogatepass error handler. Patch bySerhiy Storchaka.
• bpo-8401: assigning an int to a bytearray slice (e.g. b[3:4] = 5) nowraises an error.
• bpo-7317: Display full tracebacks when an error occurs asynchronously.Patch by Alon Horev with update by Alexey Kachayev.
• bpo-16309: Make PYTHONPATH=”” behavior the same as if PYTHONPATH not setat all.
• bpo-10189: Improve the error reporting of SyntaxErrors related to globaland nonlocal statements.
• Fix segfaults on setting __qualname__ on builtin types and attempting todelete it on any type.
• bpo-14625: Rewrite the UTF-32 decoder. It is now 3x to 4x faster. Patchwritten by Serhiy Storchaka.
• bpo-16345: Fix an infinite loop whenfromkeys on a dict subclassreceived a nonempty dict from the constructor.
• bpo-16271: Fix strange bugs that resulted from __qualname__ appearing in aclass’s __dict__ and on type.
• bpo-12805: Make bytes.join and bytearray.join faster when the separator isempty. Patch by Serhiy Storchaka.
• bpo-6074: Ensure cached bytecode files can always be updated by the userthat created them, even when the source file is read-only.
• bpo-15958: bytes.join and bytearray.join now accept arbitrary bufferobjects.
• bpo-14783: Improve int() docstring and switch docstrings for str(),range(), and slice() to use multi-line signatures.
• bpo-16160: Subclass support now works for types.SimpleNamespace.
• bpo-16148: Implement PEP 424, adding operator.length_hint andPyObject_LengthHint.
• Upgrade Unicode data (UCD) to version 6.2.
• bpo-15379: Fix passing of non-BMP characters as integers for the charmapdecoder (already working as unicode strings). Patch by Serhiy Storchaka.
• bpo-15144: Fix possible integer overflow when handling pointers as integervalues, by usingPy_uintptr_t instead ofsize_t. Patch by SerhiyStorchaka.
• bpo-15965: Explicitly castAT_FDCWD as (int). Required on Solaris 10(which definesAT_FDCWD as0xffd19553), harmless on other platforms.
• bpo-15839: Convert SystemErrors insuper() to RuntimeErrors.
• bpo-15448: Buffered IO now frees the buffer when closed, instead of whendeallocating.
• bpo-15846: Fix SystemError which happened when usingast.parse() in anexception handler on code with syntax errors.
• bpo-15897: zipimport.c doesn’t check return value of fseek(). Patch byFelipe Cruz.
• bpo-15801: Make sure mappings passed to ‘%’ formatting are actuallysubscriptable.
• bpo-15111: __import__ should propagate ImportError when raised as aside-effect of a module triggered from using fromlist.
• bpo-15022: Add pickle and comparison support to types.SimpleNamespace.

Library¶

• bpo-4331: Added functools.partialmethod (Initial patch by Alon Horev)
• bpo-13461: Fix a crash in the TextIOWrapper.tell method on 64-bitplatforms. Patch by Yogesh Chaudhari.
• bpo-18681: Fix a NameError in importlib.reload() (noticed by Weizhao Li).
• bpo-14323: Expanded the number of digits in the coefficients for the RGB– YIQ conversions so that they match the FCC NTSC versions.
• bpo-17998: Fix an internal error in regular expression engine.
• bpo-17557: Fix os.getgroups() to work with the modified behavior ofgetgroups(2) on OS X 10.8. Original patch by Mateusz Lenik.
• bpo-18608: Avoid keeping a strong reference to the locale module insidethe _io module.
• bpo-18619: Fix atexit leaking callbacks registered from sub-interpreters,and make it GC-aware.
• bpo-15699: The readline module now uses PEP 3121-style moduleinitialization, so as to reclaim allocated resources (Python callbacks) atshutdown. Original patch by Robin Schreiber.
• bpo-17616: wave.open now supports the context management protocol.
• bpo-18599: Fix name attribute of _sha1.sha1() object. It now returns‘SHA1’ instead of ‘SHA’.
• bpo-13266: Added inspect.unwrap to easily unravel __wrapped__ chains(initial patch by Daniel Urban and Aaron Iles)
• bpo-18561: Skip name in ctypes’ _build_callargs() if name is NULL.
• bpo-18559: Fix NULL pointer dereference error in _pickle module
• bpo-18556: Check the return type of PyUnicode_AsWideChar() in ctype’sU_set().
• bpo-17818: aifc.getparams now returns a namedtuple.
• bpo-18549: Eliminate dead code in socket_ntohl()
• bpo-18530: Remove additional stat call from posixpath.ismount. Patch byAlex Gaynor.
• bpo-18514: Fix unreachable Py_DECREF() call in PyCData_FromBaseObj()
• bpo-9177: Calling read() or write() now raises ValueError, notAttributeError, on a closed SSL socket. Patch by Senko Rasic.
• bpo-18513: Fix behaviour of cmath.rect w.r.t. signed zeros on OS X 10.8 +gcc.
• bpo-18479: Changed venv Activate.ps1 to make deactivate a function, andremoved Deactivate.ps1.
• bpo-18480: Add missing call to PyType_Ready to the _elementtree extension.
• bpo-17778: Fix test discovery for test_multiprocessing. (Patch by ZacharyWare.)
• bpo-18393: The private module _gestalt and private functionsplatform._mac_ver_gestalt, platform._mac_ver_lookup and platform._bcd2strhave been removed. This does not affect the public interface of theplatform module.
• bpo-17482: functools.update_wrapper (and functools.wraps) now set the__wrapped__ attribute correctly even if the underlying function has a__wrapped__ attribute set.
• bpo-18431: The new email header parser now decodes RFC2047 encoded wordsin structured headers.
• bpo-18432: The sched module’s queue method was incorrectly returning aniterator instead of a list.
• bpo-18044: The new email header parser was mis-parsing encoded words wherean encoded character immediately followed the ‘?’ that follows the CTEcharacter, resulting in a decoding failure. They are now decodedcorrectly.
• bpo-18101: Tcl.split() now process strings nested in a tuple as it do withbyte strings.
• bpo-18116: getpass was always getting an error when testing /dev/tty, andthus was always falling back to stdin, and would then raise an exceptionif stdin could not be used (such as /dev/null). It also leaked an openfile. All of these issues are now fixed.
• bpo-17198: Fix a NameError in the dbm module. Patch by ValentinaMukhamedzhanova.
• bpo-18013: Fix cgi.FieldStorage to parse the W3C sample form.
• bpo-18020: improve html.escape speed by an order of magnitude. Patch byMatt Bryant.
• bpo-18347: ElementTree’s html serializer now preserves the case of closingtags.
• bpo-17261: Ensure multiprocessing’s proxies use proper address.
• bpo-18343: faulthandler.register() now keeps the previous signal handlerwhen the function is called twice, so faulthandler.unregister() restorescorrectly the original signal handler.
• bpo-17097: Make multiprocessing ignore EINTR.
• bpo-18339: Negative ints keys in unpickler.memo dict no longer cause asegfault inside the _pickle C extension.
• bpo-18240: The HMAC module is no longer restricted to bytes and acceptsany bytes-like object, e.g. memoryview. Original patch by Jonas Borgström.
• bpo-18224: Removed pydoc script from created venv, as it causes problemson Windows and adds no value over and above python -m pydoc ...
• bpo-18155: The csv module now correctly handles csv files that use adelimter character that has a special meaning in regexes, instead ofthrowing an exception.
• bpo-14360: encode_quopri can now be successfully used as an encoder whenconstructing a MIMEApplication object.
• bpo-11390: Add -o and -f command line options to the doctest CLI tospecify doctest options (and convert it to using argparse).
• bpo-18135: ssl.SSLSocket.write() now raises an OverflowError if the inputstring in longer than 2 gigabytes, and ssl.SSLContext.load_cert_chain()raises a ValueError if the password is longer than 2 gigabytes. The sslmodule does not support partial write.
• bpo-11016: Add C implementation of the stat module as _stat.
• bpo-18248: Fix libffi build on AIX.
• bpo-18259: Declare sethostname in socketmodule.c for AIX
• bpo-18147: Add diagnostic functions to ssl.SSLContext(). get_ca_list()lists all loaded CA certificates and cert_store_stats() returns amount ofloaded X.509 certs, X.509 CA certs and CRLs.
• bpo-18167: cgi.FieldStorage no longer fails to handle multipart/form-datawhen\r\n appears at end of 65535 bytes without other newlines.
• bpo-18076: Introduce importlib.util.decode_source().
• bpo-18357: add tests for dictview set difference. Patch by FraserTweedale.
• importlib.abc.SourceLoader.get_source() no longer changes SyntaxError orUnicodeDecodeError into ImportError.
• bpo-18058: Make the namespace package loader meet theimportlib.abc.InspectLoader ABC, allowing for namespace packages to workwith runpy. (See also: bpo-18057)
• bpo-17177: The imp module is pending deprecation.
• subprocess: Prevent a possible double close of parent pipe fds when thesubprocess exec runs into an error. Prevent a regular multi-close of the/dev/null fd when any of stdin, stdout and stderr was set to DEVNULL.
• bpo-18194: Introduce importlib.util.cache_from_source() andsource_from_cache() while documenting the equivalent functions in imp asdeprecated.
• bpo-17907: Document imp.new_module() as deprecated in favour oftypes.ModuleType.
• bpo-18192: Introduce importlib.util.MAGIC_NUMBER and document asdeprecated imp.get_magic().
• bpo-18149: Add filecmp.clear_cache() to manually clear the filecmp cache.Patch by Mark Levitt
• bpo-18193: Add importlib.reload().
• bpo-18157: Stop using imp.load_module() in pydoc.
• bpo-16102: Make uuid._netbios_getnode() work again on Python 3.
• bpo-17134: Add ssl.enum_cert_store() as interface to Windows’ cert store.
• bpo-18143: Implement ssl.get_default_verify_paths() in order to debug thedefault locations for cafile and capath.
• bpo-17314: Move multiprocessing.forking over to importlib.
• bpo-11959: SMTPServer and SMTPChannel now take an optional map, use ofwhich avoids affecting global state.
• bpo-18109: os.uname() now decodes fields from the locale encoding, andsocket.gethostname() now decodes the hostname from the locale encoding,instead of using the UTF-8 encoding in strict mode.
• bpo-18089: Implement importlib.abc.InspectLoader.load_module.
• bpo-18088: Introduce importlib.abc.Loader.init_module_attrs for settingmodule attributes. Leads to the pending deprecation ofimportlib.util.module_for_loader.
• bpo-17403: urllib.parse.robotparser normalizes the urls before adding toruleline. This helps in handling certain types invalid urls in aconservative manner. Patch contributed by Mher Movsisyan.
• bpo-18070: Have importlib.util.module_for_loader() set attributesunconditionally in order to properly support reloading.
• Added importlib.util.module_to_load to return a context manager to providethe proper module object to load.
• bpo-18025: Fixed a segfault in io.BufferedIOBase.readinto() when rawstream’s read() returns more bytes than requested.
• bpo-18011: As was originally intended, base64.b32decode() now raises abinascii.Error if there are non-b32-alphabet characters present in theinput string, instead of a TypeError.
• bpo-18072: Implement importlib.abc.InspectLoader.get_code() andimportlib.abc.ExecutionLoader.get_code().
• bpo-8240: Set the SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER flag on SSL sockets.
• bpo-17269: Workaround for socket.getaddrinfo crash on MacOS X with portNone or “0” and flags AI_NUMERICSERV.
• bpo-16986: ElementTree now correctly works with string input when theinternal XML encoding is not UTF-8 or US-ASCII.
• bpo-17996: socket module now exposes AF_LINK constant on BSD and OSX.
• bpo-17900: Allowed pickling of recursive OrderedDicts. Decreased pickledsize and pickling time.
• bpo-17914: Add os.cpu_count(). Patch by Yogesh Chaudhari, based on aninitial patch by Trent Nelson.
• bpo-17812: Fixed quadratic complexity of base64.b32encode(). Optimizebase64.b32encode() and base64.b32decode() (speed up to 3x).
• bpo-17980: Fix possible abuse of ssl.match_hostname() for denial ofservice using certificates with many wildcards (CVE-2013-2099).
• bpo-15758: Fix FileIO.readall() so it no longer has O(n**2) complexity.
• bpo-14596: The struct.Struct() objects now use a more compactimplementation.
• bpo-17981: logging’s SysLogHandler now closes the socket when it catchessocket OSErrors.
• bpo-17964: Fix os.sysconf(): the return type of the C sysconf() functionis long, not int.
• Fix typos in the multiprocessing module.
• bpo-17754: Make ctypes.util.find_library() independent of the locale.
• bpo-17968: Fix memory leak in os.listxattr().
• bpo-17606: Fixed support of encoded byte strings in the XMLGeneratorcharacters() and ignorableWhitespace() methods. Original patch bySebastian Ortiz Vasquez.
• bpo-17732: Ignore distutils.cfg options pertaining to install paths if avirtual environment is active.
• bpo-17915: Fix interoperability of xml.sax with file objects returned bycodecs.open().
• bpo-16601: Restarting iteration over tarfile really restarts rather thancontinuing from where it left off. Patch by Michael Birtwell.
• bpo-17289: The readline module now plays nicer with external modules orapplications changing the rl_completer_word_break_characters globalvariable. Initial patch by Bradley Froehle.
• bpo-12181: select module: Fix struct kevent definition on OpenBSD 64-bitplatforms. Patch by Federico Schwindt.
• bpo-11816: multiple improvements to the dis module: get_instructionsgenerator, ability to redirect output to a file, Bytecode and Instructionabstractions. Patch by Nick Coghlan, Ryan Kelly and Thomas Kluyver.
• bpo-13831: Embed stringification of remote traceback in local tracebackraised when pool task raises an exception.
• bpo-15528: Add weakref.finalize to support finalization using weakrefcallbacks.
• bpo-14173: Avoid crashing when reading a signal handler during interpretershutdown.
• bpo-15902: Fix imp.load_module() accepting None as a file when loading anextension module.
• bpo-13721: SSLSocket.getpeercert() and SSLSocket.do_handshake() now raisean OSError with ENOTCONN, instead of an AttributeError, when the SSLSocketis not connected.
• bpo-14679: add an __all__ (that contains only HTMLParser) to html.parser.
• bpo-17802: Fix an UnboundLocalError in html.parser. Initial tests byThomas Barlow.
• bpo-17358: Modules loaded by imp.load_source() and load_compiled() (and byextention load_module()) now have a better chance of working whenreloaded.
• bpo-17804: New functionstruct.iter_unpack allows for streaming structunpacking.
• bpo-17830: When keyword.py is used to update a keyword file, it nowpreserves the line endings of the original file.
• bpo-17272: Making the urllib.request’s Request.full_url a descriptor.Fixes bugs with assignment to full_url. Patch by Demian Brecht.
• bpo-17353: Plistlib emitted empty data tags with deeply nesteddatastructures
• bpo-11714: Use ‘with’ statements to assure a Semaphore releases acondition variable. Original patch by Thomas Rachel.
• bpo-16624:subprocess.check_output now accepts aninput argument,allowing the subprocess’s stdin to be provided as a (byte) string. Patchby Zack Weinberg.
• bpo-17795: Reverted backwards-incompatible change in SysLogHandler withUnix domain sockets.
• bpo-16694: Add a pure Python implementation of the operator module. Patchby Zachary Ware.
• bpo-11182: remove the unused and undocumented pydoc.Scanner class. Patchby Martin Morrison.
• bpo-17741: Add ElementTree.XMLPullParser, an event-driven parser fornon-blocking applications.
• bpo-17555: Fix ForkAwareThreadLock so that size of after fork registrydoes not grow exponentially with generation of process.
• bpo-17707: fix regression in multiprocessing.Queue’s get() method where itdid not block for short timeouts.
• bpo-17720: Fix the Python implementation of pickle.Unpickler to correctlyprocess the APPENDS opcode when it is used on non-list objects.
• bpo-17012: shutil.which() no longer falls back to the PATH environmentvariable if an empty path argument is specified. Patch by SerhiyStorchaka.
• bpo-17710: Fix pickle raising a SystemError on bogus input.
• bpo-17341: Include the invalid name in the error messages from re aboutinvalid group names.
• bpo-17702: os.environ now raises KeyError with the original environmentvariable name (str on UNIX), instead of using the encoded name (bytes onUNIX).
• bpo-16163: Make the importlib based version of pkgutil.iter_importers workfor submodules. Initial patch by Berker Peksag.
• bpo-16804: Fix a bug in the ‘site’ module that caused running ‘python -S-m site’ to incorrectly throw an exception.
• bpo-15480: Remove the deprecated and unused TYPE_INT64 code from marshal.Initial patch by Daniel Riti.
• bpo-2118: SMTPException is now a subclass of OSError.
• bpo-17016: Get rid of possible pointer wraparounds and integer overflowsin the re module. Patch by Nickolai Zeldovich.
• bpo-16658: add missing return to HTTPConnection.send(). Patch by JeffKnupp.
• bpo-9556: the logging package now allows specifying a time-of-day for aTimedRotatingFileHandler to rotate.
• bpo-14971: unittest test discovery no longer gets confused when a functionhas a different __name__ than its name in the TestCase class dictionary.
• bpo-17487: The wave getparams method now returns a namedtuple rather thana plain tuple.
• bpo-17675: socket repr() provides local and remote addresses (if any).Patch by Giampaolo Rodola’
• bpo-17093: Make the ABCs in importlib.abc provide default values or raisereasonable exceptions for their methods to make them more amenable tosuper() calls.
• bpo-17566: Make importlib.abc.Loader.module_repr() optional instead of anabstractmethod; now it raises NotImplementedError so as to be ignored bydefault.
• bpo-17678: Remove the use of deprecated method in http/cookiejar.py bychanging the call to get_origin_req_host() to origin_req_host.
• bpo-17666: Fix reading gzip files with an extra field.
• bpo-16475: Support object instancing, recursion and interned strings inmarshal
• bpo-17502: Process DEFAULT values in mock side_effect that returnsiterator.
• bpo-16795: On the ast.arguments object, unify vararg with varargannotationand kwarg and kwargannotation. Change the column offset of ast.Attributeto be at the attribute name.
• bpo-17434: Properly raise a SyntaxError when a string occurs betweenfuture imports.
• bpo-17117: Import and @importlib.util.set_loader now set __loader__ whenit has a value of None or the attribute doesn’t exist.
• bpo-17032: The “global” in the “NameError: global name ‘x’ is not defined”error message has been removed. Patch by Ram Rachum.
• bpo-18080: When building a C extension module on OS X, if the compiler isoverriden with the CC environment variable, use the new compiler as thedefault for linking if LDSHARED is not also overriden. This restoresDistutils behavior introduced in 3.2.3 and inadvertently dropped in 3.3.0.
• bpo-18113: Fixed a refcount leak in the curses.panel module’sset_userptr() method. Reported by Atsuo Ishimoto.
• Implement PEP 443 “Single-dispatch generic functions”.
• Implement PEP 435 “Adding an Enum type to the Python standard library”.
• bpo-15596: Faster pickling of unicode strings.
• bpo-17572: Avoid chained exceptions when passing bad directives totime.strptime(). Initial patch by Claudiu Popa.
• bpo-17435: threading.Timer’s __init__ method no longer uses mutabledefault values for the args and kwargs parameters.
• bpo-17526: fix an IndexError raised while passing code without filename toinspect.findsource(). Initial patch by Tyler Doyle.
• bpo-17540: Added style parameter to logging formatter configuration bydict.
• bpo-16692: The ssl module now supports TLS 1.1 and TLS 1.2. Initial patchby Michele Orrù.
• bpo-17025: multiprocessing: Reduce Queue and SimpleQueue contention.
• bpo-17536: Add to webbrowser’s browser list: www-browser, x-www-browser,iceweasel, iceape.
• bpo-17150: pprint now uses line continuations to wrap long stringliterals.
• bpo-17488: Change the subprocess.Popen bufsize parameter default valuefrom unbuffered (0) to buffering (-1) to match the behavior existing codeexpects and match the behavior of the subprocess module in Python 2 toavoid introducing hard to track down bugs.
• bpo-17521: Corrected non-enabling of logger following two calls tofileConfig().
• bpo-17508: Corrected logging MemoryHandler configuration in dictConfig()where the target handler wasn’t configured first.
• bpo-17209: curses.window.get_wch() now correctly handles KeyboardInterrupt(CTRL+c).
• bpo-5713: smtplib now handles 421 (closing connection) error codes whensending mail by closing the socket and reporting the 421 error code viathe exception appropriate to the command that received the error response.
• bpo-16997: unittest.TestCase now provides a subTest() context manager toprocedurally generate, in an easy way, small test instances.
• bpo-17485: Also delete the Request Content-Length header if the dataattribute is deleted. (Follow on to issueIssue #16464).
• bpo-15927: CVS now correctly parses escaped newlines and carriage whenparsing with quoting turned off.
• bpo-17467: add readline and readlines support to mock_open inunittest.mock.
• bpo-13248: removed deprecated and undocumented difflib.isbjunk,isbpopular.
• bpo-17192: Update the ctypes module’s libffi to v3.0.13. Thisspecifically addresses a stack misalignment issue on x86 and issues onsome more recent platforms.
• bpo-8862: Fixed curses cleanup when getkey is interrputed by a signal.
• bpo-17443: imaplib.IMAP4_stream was using the default unbuffered IO insubprocess, but the imap code assumes buffered IO. In Python2 this workedby accident. IMAP4_stream now explicitly uses buffered IO.
• bpo-17476: Fixed regression relative to Python2 in undocumented pydoc‘allmethods’; it was missing unbound methods on the class.
• bpo-17474: Remove the deprecated methods of Request class.
• bpo-16709: unittest discover order is no-longer filesystem specific. Patchby Jeff Ramnani.
• Use the HTTPS PyPI url for upload, overriding any plain HTTP URL inpypirc.
• bpo-5024: sndhdr.whichhdr now returns the frame count for WAV files ratherthan -1.
• bpo-17460: Remove the strict argument of HTTPConnection and removing theDeprecationWarning being issued from 3.2 onwards.
• bpo-16880: Do not assume _imp.load_dynamic() is defined in the imp module.
• bpo-16389: Fixed a performance regression relative to Python 3.1 in thecaching of compiled regular expressions.
• Added missing FeedParser and BytesFeedParser to email.parser.__all__.
• bpo-17431: Fix missing import of BytesFeedParser in email.parser.
• bpo-12921: http.server’s send_error takes an explain argument to send moreinformation in response. Patch contributed by Karl.
• bpo-17414: Add timeit, repeat, and default_timer to timeit.__all__.
• bpo-1285086: Get rid of the refcounting hack and speed upurllib.parse.unquote() and urllib.parse.unquote_to_bytes().
• bpo-17099: Have importlib.find_loader() raise ValueError when __loader__is not set, harmonizing with what happens when the attribute is set toNone.
• Expose the O_PATH constant in the os module if it is available.
• bpo-17368: Fix an off-by-one error in the Python JSON decoder that causeda failure while decoding empty object literals when object_pairs_hook wasspecified.
• bpo-17385: Fix quadratic behavior in threading.Condition. The FIFO queuenow uses a deque instead of a list.
• bpo-15806: Add contextlib.ignore(). This creates a context manager toignore specified exceptions, replacing the “except SomeException: pass”idiom.
• bpo-14645: The email generator classes now produce output using thespecified linesep throughout. Previously if the prolog, epilog, or bodywere stored with a different linesep, that linesep was used. This fixcorrects an RFC non- compliance issue with smtplib.send_message.
• bpo-17278: Fix a crash in heapq.heappush() and heapq.heappop() when thelist is being resized concurrently.
• bpo-16962: Use getdents64 instead of the obsolete getdents syscall in thesubprocess module on Linux.
• bpo-16935: unittest now counts the module as skipped if it raisesSkipTest, instead of counting it as an error. Patch by Zachary Ware.
• bpo-17018: Make Process.join() retry if os.waitpid() fails with EINTR.
• bpo-17223: array module: Fix a crasher when converting an array containinginvalid characters (outside range [U+0000; U+10ffff]) to Unicode:repr(array), str(array) and array.tounicode(). Patch written by ManuelJacob.
• bpo-17197: profile/cProfile modules refactored so that code of run() andrunctx() utility functions is not duplicated in both modules.
• bpo-14720: sqlite3: Convert datetime microseconds correctly. Patch by LoweThiderman.
• bpo-15132: Allow a list for the defaultTest argument ofunittest.TestProgram. Patch by Jyrki Pulliainen.
• bpo-17225: JSON decoder now counts columns in the first line starting with1, as in other lines.
• bpo-6623: Added explicit DeprecationWarning for ftplib.netrc, which hasbeen deprecated and undocumented for a long time.
• bpo-13700: Fix byte/string handling in imaplib authentication when anauthobject is specified.
• bpo-13153: Tkinter functions now raise TclError instead of ValueError whena string argument contains non-BMP character.
• bpo-9669: Protect re against infinite loops on zero-width matching innon-greedy repeat. Patch by Matthew Barnett.
• bpo-13169: The maximal repetition number in a regular expression has beenincreased from 65534 to 2147483647 (on 32-bit platform) or 4294967294 (on64-bit).
• bpo-17143: Fix a missing import in the trace module. Initial patch byBerker Peksag.
• bpo-15220: email.feedparser’s line splitting algorithm is now simpler andfaster.
• bpo-16743: Fix mmap overflow check on 32 bit Windows.
• bpo-16996: webbrowser module now uses shutil.which() to find a web-browseron the executable search path.
• bpo-16800: tempfile.gettempdir() no longer left temporary files when thedisk is full. Original patch by Amir Szekely.
• bpo-17192: Import libffi-3.0.12.
• bpo-16564: Fixed regression relative to Python2 in the operation ofemail.encoders.encode_7or8bit when used with binary data.
• bpo-17052: unittest discovery should use self.testLoader.
• bpo-4591: Uid and gid values larger than 2**31 are supported now.
• bpo-17141: random.vonmisesvariate() no longer hangs for large kappas.
• bpo-17149: Fix random.vonmisesvariate to always return results in [0,2*math.pi].
• bpo-1470548: XMLGenerator now works with binary output streams.
• bpo-6975: os.path.realpath() now correctly resolves multiple nestedsymlinks on POSIX platforms.
• bpo-13773: sqlite3.connect() gets a newuri parameter to pass thefilename as a URI, allowing to pass custom options.
• bpo-16564: Fixed regression relative to Python2 in the operation ofemail.encoders.encode_noop when used with binary data.
• bpo-10355: The mode, name, encoding and newlines properties now work onSpooledTemporaryFile objects even when they have not yet rolled over.Obsolete method xreadline (which has never worked in Python 3) has beenremoved.
• bpo-16686: Fixed a lot of bugs in audioop module. Fixed crashes inavgpp(), maxpp() and ratecv(). Fixed an integer overflow in add(),bias(), and ratecv(). reverse(), lin2lin() and ratecv() no more loseprecision for 32-bit samples. max() and rms() no more returns a negativeresult and various other functions now work correctly with 32-bit sample-0x80000000.
• bpo-17073: Fix some integer overflows in sqlite3 module.
• bpo-16723: httplib.HTTPResponse no longer marked closed when theconnection is automatically closed.
• bpo-15359: Add CAN_BCM protocol support to the socket module. Patch byBrian Thorne.
• bpo-16948: Fix quoted printable body encoding for non-latin1 charactersets in the email package.
• bpo-16811: Fix folding of headers with no value in the provisional emailpolicies.
• bpo-17132: Update symbol for “yield from” grammar changes.
• bpo-17076: Make copying of xattrs more tolerant of missing FS support.Patch by Thomas Wouters.
• bpo-17089: Expat parser now correctly works with string input when theinternal XML encoding is not UTF-8 or US-ASCII. It also now accepts bytesand strings larger than 2 GiB.
• bpo-6083: Fix multiple segmentation faults occured when PyArg_ParseTupleparses nested mutating sequence.
• bpo-5289: Fix ctypes.util.find_library on Solaris.
• bpo-17106: Fix a segmentation fault in io.TextIOWrapper when an underlyingstream or a decoder produces data of an unexpected type (i.e. whenio.TextIOWrapper initialized with text stream or use bytes-to-bytescodec).
• bpo-17015: When it has a spec, a Mock object now inspects its signaturewhen matching calls, so that arguments can be matched positionally or byname.
• bpo-15633: httplib.HTTPResponse is now mark closed when the server sendsless than the advertised Content-Length.
• bpo-12268: The io module file object write methods no longer abort earlywhen one of its write system calls is interrupted (EINTR).
• bpo-6972: The zipfile module no longer overwrites files outside of itsdestination path when extracting malicious zip files.
• bpo-4844: ZipFile now raises BadZipFile when opens a ZIP file with anincomplete “End of Central Directory” record. Original patch by GuilhermePolo and Alan McIntyre.
• bpo-17071: Signature.bind() now works when one of the keyword arguments isnamedself.
• bpo-12004: Fix an internal error in PyZipFile when writing an invalidPython file. Patch by Ben Morgan.
• Have py_compile use importlib as much as possible to avoid codeduplication. Code now raises FileExistsError if the file path to be usedfor the byte- compiled file is a symlink or non-regular file as a warningthat import will not keep the file path type if it writes to that path.
• bpo-16972: Have site.addpackage() consider already known paths even whennone are explicitly passed in. Bug report and fix by Kirill.
• bpo-1602133: on Mac OS X a shared library build (--enable-shared) nowfills theos.environ variable correctly.
• bpo-15505:unittest.installHandler no longer assumes SIGINT handler isset to a callable object.
• bpo-13454: Fix a crash when deleting an iterator created byitertools.tee() if all other iterators were very advanced before.
• bpo-12411: Fix to cgi.parse_multipart to correctly use bytes boundariesand bytes data. Patch by Jonas Wagner.
• bpo-16957: shutil.which() no longer searches a bare file name in thecurrent directory on Unix and no longer searches a relative file path witha directory part in PATH directories. Patch by Thomas Kluyver.
• bpo-1159051: GzipFile now raises EOFError when reading a corrupted filewith truncated header or footer.
• bpo-16993: shutil.which() now preserves the case of the path and extensionon Windows.
• bpo-16992: On Windows in signal.set_wakeup_fd, validate the filedescriptor argument.
• bpo-16422: For compatibility with the Python version, the C version ofdecimal now uses strings instead of integers for rounding mode constants.
• bpo-15861: tkinter now correctly works with lists and tuples containingstrings with whitespaces, backslashes or unbalanced braces.
• bpo-9720: zipfile now writes correct local headers for files larger than 4GiB.
• bpo-16955: Fix the poll() method for multiprocessing’s socket connectionson Windows.
• SSLContext.load_dh_params() now properly closes the input file.
• bpo-15031: Refactor some .pyc management code to cut down on codeduplication. Thanks to Ronan Lamy for the report and taking an initialstab at the problem.
• bpo-16398: Optimize deque.rotate() so that it only moves pointers anddoesn’t touch the underlying data with increfs and decrefs.
• bpo-16900: Issue a ResourceWarning when an ssl socket is left unclosed.
• bpo-13899:\A,\Z, and\B now correctly match the A, Z, and Bliterals when used inside character classes (e.g.'[\A]'). Patch byMatthew Barnett.
• bpo-15545: Fix regression in sqlite3’s iterdump method where it wasfailing if the connection used a row factory (such as sqlite3.Row) thatproduced unsortable objects. (Regression was introduced by fix for 9750).
• fcntl: add F_DUPFD_CLOEXEC constant, available on Linux 2.6.24+.
• bpo-15972: Fix error messages when os functions expecting a file name orfile descriptor receive the incorrect type.
• bpo-8109: The ssl module now has support for server-side SNI, thanks to aSSLContext.set_servername_callback() method. Patch by Daniel Black.
• bpo-16860: In tempfile, use O_CLOEXEC when available to set theclose-on-exec flag atomically.
• bpo-16674: random.getrandbits() is now 20-40% faster for small integers.
• bpo-16009: JSON error messages now provide more information.
• bpo-16828: Fix error incorrectly raised by bz2.compress(b’‘) andbz2.BZ2Compressor.compress(b’‘). Initial patch by Martin Packman.
• bpo-16833: In http.client.HTTPConnection, do not concatenate the requestheaders and body when the payload exceeds 16 KB, since it can consume morememory for no benefit. Patch by Benno Leslie.
• bpo-16541: tk_setPalette() now works with keyword arguments.
• bpo-16820: In configparser,parser.popitem() no longer raisesValueError. This makesparser.clean() work correctly.
• bpo-16820: In configparser,parser['section']={} now preservessection order within the parser. This makesparser.update() preservesection order as well.
• bpo-16820: In configparser,parser['DEFAULT']={} now correctlyclears previous values stored in the default section. Same goes forparser.update({'DEFAULT':{}}).
• bpo-9586: Redefine SEM_FAILED on MacOSX to keep compiler happy.
• bpo-16787: Increase asyncore and asynchat default output buffers size, todecrease CPU usage and increase throughput.
• bpo-10527: make multiprocessing use poll() instead of select() ifavailable.
• bpo-16688: Now regexes contained backreferences correctly work withnon-ASCII strings. Patch by Matthew Barnett.
• bpo-16486: Make aifc files act as context managers.
• bpo-16485: Now file descriptors are closed if file header patching failedon closing an aifc file.
• bpo-16640: Run less code under a lock in sched module.
• bpo-16165: sched.scheduler.run() no longer blocks a scheduler for otherthreads.
• bpo-16641: Default values of sched.scheduler.enter() are no longermodifiable.
• bpo-16618: Make glob.glob match consistently across strings and bytesregarding leading dots. Patch by Serhiy Storchaka.
• bpo-16788: Add samestat to Lib/ntpath.py
• bpo-16713: Parsing of ‘tel’ urls using urlparse separates params frompath.
• bpo-16443: Add docstrings to regular expression match objects. Patch byAnton Kasyanov.
• bpo-15701: Fix HTTPError info method call to return the headersinformation.
• bpo-16752: Add a missing import to modulefinder. Patch by Berker Peksag.
• bpo-16646: ftplib.FTP.makeport() might lose socket error details. (patchby Serhiy Storchaka)
• bpo-16626: Fix infinite recursion in glob.glob() on Windows when thepattern contains a wildcard in the drive or UNC path. Patch by SerhiyStorchaka.
• bpo-15783: Except for the number methods, the C version of decimal nowsupports all None default values present in decimal.py. These values werelargely undocumented.
• bpo-11175: argparse.FileType now accepts encoding and errors arguments.Patch by Lucas Maystre.
• bpo-16488: epoll() objects now support thewith statement. Patch bySerhiy Storchaka.
• bpo-16298: In HTTPResponse.read(), close the socket when there is noContent-Length and the incoming stream is finished. Patch by EranRundstein.
• bpo-16049: Add abc.ABC class to enable the use of inheritance to createABCs, rather than the more cumbersome metaclass=ABCMeta. Patch by BrunoDupuis.
• Expose the TCP_FASTOPEN and MSG_FASTOPEN flags in socket when they’reavailable.
• bpo-15701: Add a .headers attribute to urllib.error.HTTPError. Patchcontributed by Berker Peksag.
• bpo-15872: Fix 3.3 regression introduced by the new fd-based shutil.rmtreethat caused it to not ignore certain errors when ignore_errors was set.Patch by Alessandro Moura and Serhiy Storchaka.
• bpo-16248: Disable code execution from the user’s home directory bytkinter when the -E flag is passed to Python. Patch by Zachary Ware.
• bpo-13390: New functionsys.getallocatedblocks() returns thenumber of memory blocks currently allocated.
• bpo-16628: Fix a memory leak in ctypes.resize().
• bpo-13614: Fix setup.py register failure with invalid rst in description.Patch by Julien Courteau and Pierre Paul Lefebvre.
• bpo-13512: Create ~/.pypirc securely (CVE-2011-4944). Initial patch byPhilip Jenvey, tested by Mageia and Debian.
• bpo-7719: Make distutils ignore.nfs* files instead of choking lateron. Initial patch by SilentGhost and Jeff Ramnani.
• bpo-13120: Allow to call pdb.set_trace() from thread. Patch by IlyaSandler.
• bpo-16585: Make CJK encoders support error handlers that return bytes perPEP 383.
• bpo-10182: The re module doesn’t truncate indices to 32 bits anymore.Patch by Serhiy Storchaka.
• bpo-16333: use (”,”, ”: ”) as default separator in json when indent isspecified, to avoid trailing whitespace. Patch by Serhiy Storchaka.
• bpo-16573: In 2to3, treat enumerate() like a consuming call, sosuperfluous list() calls aren’t added to filter(), map(), and zip() whichare directly passed enumerate().
• bpo-16464: Reset the Content-Length header when a urllib Request is reusedwith new data.
• bpo-12848: The pure Python pickle implementation now treats object lengthsas unsigned 32-bit integers, like the C implementation does. Patch bySerhiy Storchaka.
• bpo-16423: urllib.request now has support fordata: URLs. Patch byMathias Panzenböck.
• bpo-4473: Add a POP3.stls() to switch a clear-text POP3 session into anencrypted POP3 session, on supported servers. Patch by Lorenzo Catucci.
• bpo-4473: Add a POP3.capa() method to query the capabilities advertised bythe POP3 server. Patch by Lorenzo Catucci.
• bpo-4473: Ensure the socket is shutdown cleanly in POP3.close(). Patch byLorenzo Catucci.
• bpo-16522: added FAIL_FAST flag to doctest.
• bpo-15627: Add the importlib.abc.InspectLoader.source_to_code() method.
• bpo-16408: Fix file descriptors not being closed in error conditions inthe zipfile module. Patch by Serhiy Storchaka.
• bpo-14631: Add a newweakref.WeakMethod to simulate weakreferences to bound methods.
• bpo-16469: Fix exceptions from float -> Fraction and Decimal -> Fractionconversions for special values to be consistent with those for float ->int and Decimal -> int. Patch by Alexey Kachayev.
• bpo-16481: multiprocessing no longer leaks process handles on Windows.
• bpo-12428: Add a pure Python implementation of functools.partial(). Patchby Brian Thorne.
• bpo-16140: The subprocess module no longer double closes its childsubprocess.PIPE parent file descriptors on child error prior to exec().
• Remove a bare print to stdout from the subprocess module that could havehappened if the child process wrote garbage to its pre-exec error pipe.
• The subprocess module now raises its own SubprocessError instead of aRuntimeError in various error situations which should not normally happen.
• bpo-16327: The subprocess module no longer leaks file descriptors used forstdin/stdout/stderr pipes to the child when fork() fails.
• bpo-14396: Handle the odd rare case of waitpid returning 0 when notexpected in subprocess.Popen.wait().
• bpo-16411: Fix a bug where zlib.decompressobj().flush() might try toaccess previously- freed memory. Patch by Serhiy Storchaka.
• bpo-16357: fix calling accept() on a SSLSocket created throughSSLContext.wrap_socket(). Original patch by Jeff McNeil.
• bpo-16409: The reporthook callback made by the legacyurllib.request.urlretrieve API now properly supplies a constant non-zeroblock_size as it did in Python 3.2 and 2.7. This matches the behavior ofurllib.request.URLopener.retrieve.
• bpo-16431: Use the type information when constructing a Decimal subtypefrom a Decimal argument.
• bpo-15641: Clean up deprecated classes from importlib. Patch by TarasLyapun.
• bpo-16350: zlib.decompressobj().decompress() now accumulates data fromsuccessive calls after EOF in unused_data, instead of only saving theargument to the last call. decompressobj().flush() now correctly setsunused_data and unconsumed_tail. A bug in the handling of MemoryError whensetting the unconsumed_tail attribute has also been fixed. Patch by SerhiyStorchaka.
• bpo-12759: sre_parse now raises a proper error when the name of the groupis missing. Initial patch by Serhiy Storchaka.
• bpo-16152: fix tokenize to ignore whitespace at the end of the code whenno newline is found. Patch by Ned Batchelder.
• bpo-16284: Prevent keeping unnecessary references to worker functions inconcurrent.futures ThreadPoolExecutor.
• bpo-16230: Fix a crash in select.select() when one the lists changes sizewhile iterated on. Patch by Serhiy Storchaka.
• bpo-16228: Fix a crash in the json module where a list changes size whileit is being encoded. Patch by Serhiy Storchaka.
• bpo-16351: New function gc.get_stats() returns per-generation collectionstatistics.
• bpo-14897: Enhance error messages of struct.pack and struct.pack_into.Patch by Matti Mäki.
• bpo-16316: mimetypes now recognizes the .xz and .txz (.tar.xz) extensions.Patch by Serhiy Storchaka.
• bpo-12890: cgitb no longer prints spurious <p> tags in text mode when thelogdir option is specified.
• bpo-16307: Fix multiprocessing.Pool.map_async not calling its callbacks.Patch by Janne Karila.
• bpo-16305: Fix a segmentation fault occurring when interruptingmath.factorial.
• bpo-16116: Fix include and library paths to be correct when building Cextensions in venvs.
• bpo-16245: Fix the value of a few entities in html.entities.html5.
• bpo-16301: Fix the localhost verification in urllib/request.py forfile://urls.
• bpo-16250: Fix the invocations of URLError which had misplaced filenameattribute for exception.
• bpo-10836: Fix exception raised when file not found in urlretrieve Initialpatch by Ezio Melotti.
• bpo-14398: Fix size truncation and overflow bugs in the bz2 module.
• bpo-12692: Fix resource leak in urllib.request when talking to an HTTPserver that does not include aConnection:close header in itsresponses.
• bpo-12034: Fix bogus caching of result in check_GetFinalPathNameByHandle.Patch by Atsuo Ishimoto.
• Improve performance oflzma.LZMAFile (see alsoissue #16034).
• bpo-16220: wsgiref now always calls close() on an iterable response. Patchby Brent Tubbs.
• bpo-16270: urllib may hang when used for retrieving files via FTP by usinga context manager. Patch by Giampaolo Rodola’.
• bpo-16461: Wave library should be able to deal with 4GB wav files, andsample rate of 44100 Hz.
• bpo-16176: Properly identify Windows 8 via platform.platform()
• bpo-16088: BaseHTTPRequestHandler’s send_error method includes aContent-Length header in it’s response now. Patch by Antoine Pitrou.
• bpo-16114: The subprocess module no longer provides a misleading errormessage stating that args[0] did not exist when either the cwd orexecutable keyword arguments specified a path that did not exist.
• bpo-16169: Fix ctypes.WinError()’s confusion between errno and winerror.
• bpo-16110: logging.fileConfig now accepts a pre-initialised ConfigParserinstance.
• bpo-1492704: shutil.copyfile() raises a distinct SameFileError now ifsource and destination are the same file. Patch by Atsuo Ishimoto.
• bpo-13896: Make shelf instances work with ‘with’ as context managers.Original patch by Filip Gruszczyński.
• bpo-15417: Add support for csh and fish in venv activation scripts.
• bpo-14377: ElementTree.write and some of the module-level functions have anew parameter -short_empty_elements. It controls how elements with nocontents are emitted.
• bpo-16089: Allow ElementTree.TreeBuilder to work again with a non-Elementelement_factory (fixes a regression in SimpleTAL).
• bpo-9650: List commonly used format codes in time.strftime andtime.strptime docsttings. Original patch by Mike Hoy.
• bpo-15452: logging configuration socket listener now has a verify optionthat allows an application to apply a verification function to thereceived configuration data before it is acted upon.
• bpo-16034: Fix performance regressions in the newbz2.BZ2Fileimplementation. Initial patch by Serhiy Storchaka.
• pty.spawn() now returns the child process status returned byos.waitpid().
• bpo-15756:subprocess.poll() now properly handleserrno.ECHILD toreturn a returncode of 0 when the child has already exited or cannot bewaited on.
• bpo-15323: Improve failure message ofMock.assert_called_once_with().
• bpo-16064:unittest-m claims executable is “python”, not “python3”.
• bpo-12376: Pass on parameters inTextTestResult.__init__() super call.
• bpo-15222: Insert blank line after each message in mbox mailboxes.
• bpo-16013: Fixcsv.Reader parsing issue with ending quote characters.Patch by Serhiy Storchaka.
• bpo-15421: Fix an OverflowError inCalendar.itermonthdates() afterdatetime.MAXYEAR. Patch by Cédric Krier.
• bpo-16112: platform.architecture does not correctly escape argument to/usr/bin/file. Patch by David Benjamin.
• bpo-15970:xml.etree.ElementTree now serializes correctly the empty HTMLelements ‘meta’ and ‘param’.
• bpo-15842: TheSocketIO.{readable,writable,seekable} methods now raiseValueError when the file-like object is closed. Patch by AlessandroMoura.
• bpo-15876: Fix a refleak in thecurses module: window.encoding.
• bpo-15881: Fixatexit hook inmultiprocessing. Original patch byChris McDonough.
• bpo-15841: The readable(), writable() and seekable() methods ofio.BytesIO andio.StringIO objects now raise ValueError when theobject has been closed. Patch by Alessandro Moura.
• bpo-15447: Usesubprocess.DEVNULL in webbrowser, instead of openingos.devnull explicitly and leaving it open.
• bpo-15509:webbrowser.UnixBrowser no longer passes empty arguments toPopen when%action substitutions produce empty strings.
• bpo-12776: Callargparse type function (specified by add_argument) onlyonce. Before, the type function was called twice in the case where thedefault was specified and the argument was given as well. This wasespecially problematic for the FileType type, as a default file wouldalways be opened, even if a file argument was specified on the commandline. (See also: bpo-11839)
• bpo-15906: Fix a regression in argparse caused by the preceding change,whenaction='append',type='str' anddefault=[].
• bpo-16113: Added sha3 module based on the Keccak reference implementation3.2. Thehashlib module has four additional hash algorithms:sha3_224,sha3_256,sha3_384 andsha3_512. As part of the patch some commoncode was moved from _hashopenssl.c to hashlib.h.
• ctypes.call_commethod was removed, since its only usage was in the defunctsamples directory.
• bpo-16692: Added TLSv1.1 and TLSv1.2 support for the ssl modules.
• bpo-16832: add abc.get_cache_token() to expose cache validity checkingsupport in ABCMeta.

IDLE¶

• bpo-18429: Format / Format Paragraph, now works when comment blocks areselected. As with text blocks, this works best when the selection onlyincludes complete lines.
• bpo-18226: Add docstrings and unittests for FormatParagraph.py. Originalpatches by Todd Rovito and Phil Webster.
• bpo-18279: Format - Strip trailing whitespace no longer marks a file aschanged when it has not been changed. This fix followed the addition of atest file originally written by Phil Webster (the issue’s main goal).
• bpo-7136: In the Idle File menu, “New Window” is renamed “New File”. Patchby Tal Einat, Roget Serwy, and Todd Rovito.
• Remove dead imports of imp.
• bpo-18196: Avoid displaying spurious SystemExit tracebacks.
• bpo-5492: Avoid traceback when exiting IDLE caused by a race condition.
• bpo-17511: Keep IDLE find dialog open after clicking “Find Next”. Originalpatch by Sarah K.
• bpo-18055: Move IDLE off of imp and on to importlib.
• bpo-15392: Create a unittest framework for IDLE. Initial patch byRajagopalasarma Jayakrishnan. See Lib/idlelib/idle_test/README.txt for howto run Idle tests.
• bpo-14146: Highlight source line while debugging on Windows.
• bpo-17838: Allow sys.stdin to be reassigned.
• bpo-13495: Avoid loading the color delegator twice in IDLE.
• bpo-17798: Allow IDLE to edit new files when specified on command line.
• bpo-14735: Update IDLE docs to omit “Control-z on Windows”.
• bpo-17532: Always include Options menu for IDLE on OS X. Patch byGuilherme Simões.
• bpo-17585: Fixed IDLE regression. Now closes when using exit() or quit().
• bpo-17657: Show full Tk version in IDLE’s about dialog. Patch by ToddRovito.
• bpo-17613: Prevent traceback when removing syntax colorizer in IDLE.
• bpo-1207589: Backwards-compatibility patch for right-click menu in IDLE.
• bpo-16887: IDLE now accepts Cancel in tabify/untabify dialog box.
• bpo-17625: In IDLE, close the replace dialog after it is used.
• bpo-14254: IDLE now handles readline correctly across shell restarts.
• bpo-17614: IDLE no longer raises exception when quickly closing a file.
• bpo-6698: IDLE now opens just an editor window when configured to do so.
• bpo-8900: Using keyboard shortcuts in IDLE to open a file no longer raisesan exception.
• bpo-6649: Fixed missing exit status in IDLE. Patch by Guilherme Polo.
• bpo-17114: IDLE now uses non-strict config parser.
• bpo-9290: In IDLE the sys.std* streams now implement io.TextIOBaseinterface and support all mandatory methods and properties.
• bpo-5066: Update IDLE docs. Patch by Todd Rovito.
• bpo-16829: IDLE printing no longer fails if there are spaces or otherspecial characters in the file path.
• bpo-16491: IDLE now prints chained exception tracebacks.
• bpo-16819: IDLE method completion now correctly works for bytes literals.
• bpo-16504: IDLE now catches SyntaxErrors raised by tokenizer. Patch byRoger Serwy.
• bpo-16511: Use default IDLE width and height if config param is not valid.Patch Serhiy Storchaka.
• bpo-1207589: Add Cut/Copy/Paste items to IDLE right click Context Menu.Patch by Todd Rovito.
• bpo-16123: IDLE - deprecate running without a subprocess. Patch by RogerSerwy.

Tests¶

• bpo-1666318: Add a test that shutil.copytree() retains directorypermissions. Patch by Catherine Devlin.
• bpo-18273: move the tests in Lib/test/json_tests to Lib/test/test_json andmake them discoverable by unittest. Patch by Zachary Ware.
• Fix a fcntl test case on KFreeBSD, Debian #708653 (Petr Salinger).
• bpo-18396: Fix spurious test failure in test_signal on Windows whenfaulthandler is enabled (Patch by Jeremy Kloth)
• bpo-17046: Fix broken test_executable_without_cwd in test_subprocess.
• bpo-15415: Add new temp_dir() and change_cwd() context managers totest.support, and refactor temp_cwd() to use them. Patch by ChrisJerdonek.
• bpo-15494: test.support is now a package rather than a module (Initialpatch by Indra Talip)
• bpo-17944: test_zipfile now discoverable and uses subclassing to generatetests for different compression types. Fixed a bug with skipping sometests due to use of exhausted iterators.
• bpo-18266: test_largefile now works with unittest test discovery andsupports running only selected tests. Patch by Zachary Ware.
• bpo-17767: test_locale now works with unittest test discovery. Originalpatch by Zachary Ware.
• bpo-18375: Assume –randomize when –randseed is used for running thetestsuite.
• bpo-11185: Fix test_wait4 under AIX. Patch by Sébastien Sablé.
• bpo-18207: Fix test_ssl for some versions of OpenSSL that ignore secondsin ASN1_TIME fields.
• bpo-18094: test_uuid no longer reports skipped tests as passed.
• bpo-17992: Add timeouts to asyncore and asynchat tests so that they won’taccidentally hang.
• bpo-17833: Fix test_gdb failures seen on machines where debug symbols forglibc are available (seen on PPC64 Linux).
• bpo-7855: Add tests for ctypes/winreg for issues found in IronPython.Initial patch by Dino Viehland.
• bpo-11078: test___all__ now checks for duplicates in __all__. Initialpatch by R. David Murray.
• bpo-17712: Fix test_gdb failures on Ubuntu 13.04.
• bpo-17835: Fix test_io when the default OS pipe buffer size is larger thanone million bytes.
• bpo-17065: Use process-unique key for winreg tests to avoid failures iftest is run multiple times in parallel (eg: on a buildbot host).
• bpo-12820: add tests for the xml.dom.minicompat module. Patch by JohnChandler and Phil Connell.
• bpo-17691: test_univnewlines now works with unittest test discovery. Patchby Zachary Ware.
• bpo-17790: test_set now works with unittest test discovery. Patch byZachary Ware.
• bpo-17789: test_random now works with unittest test discovery. Patch byZachary Ware.
• bpo-17779: test_osx_env now works with unittest test discovery. Patch byZachary Ware.
• bpo-17766: test_iterlen now works with unittest test discovery. Patch byZachary Ware.
• bpo-17690: test_time now works with unittest test discovery. Patch byZachary Ware.
• bpo-17692: test_sqlite now works with unittest test discovery. Patch byZachary Ware.
• bpo-11995: test_pydoc doesn’t import all sys.path modules anymore.
• bpo-17448: test_sax now skips if there are no xml parsers availableinstead of raising an ImportError.
• bpo-11420: make test suite pass with -B/DONTWRITEBYTECODE set. Initialpatch by Thomas Wouters.
• bpo-10652: make tcl/tk tests run after __all__ test, patch by ZacharyWare.
• bpo-11963: remove human verification from test_parser and test_subprocess.
• bpo-11732: add a new suppress_crash_popup() context manager totest.support that disables crash popups on Windows and use it intest_faulthandler and test_capi.
• bpo-13898: test_ssl no longer prints a spurious stack trace on Ubuntu.
• bpo-17283: Share code between__main__.py andregrtest.py inLib/test.
• bpo-17249: convert a test in test_capi to use unittest and reap threads.
• bpo-17107: Test client-side SNI support in urllib.request thanks to thenew server-side SNI support in the ssl module. Initial patch by DanielBlack.
• bpo-17041: Fix testing when Python is configured with the–without-doc-strings.
• bpo-16923: Fix ResourceWarnings in test_ssl.
• bpo-15539: Added regression tests for Tools/scripts/pindent.py.
• bpo-17479: test_io now works with unittest test discovery. Patch byZachary Ware.
• bpo-17066: test_robotparser now works with unittest test discovery. Patchby Zachary Ware.
• bpo-17334: test_index now works with unittest test discovery. Patch byZachary Ware.
• bpo-17333: test_imaplib now works with unittest test discovery. Patch byZachary Ware.
• bpo-17082: test_dbm* now work with unittest test discovery. Patch byZachary Ware.
• bpo-17079: test_ctypes now works with unittest test discovery. Patch byZachary Ware.
• bpo-17304: test_hash now works with unittest test discovery. Patch byZachary Ware.
• bpo-17303: test_future* now work with unittest test discovery. Patch byZachary Ware.
• bpo-17163: test_file now works with unittest test discovery. Patch byZachary Ware.
• bpo-16925: test_configparser now works with unittest test discovery. Patchby Zachary Ware.
• bpo-16918: test_codecs now works with unittest test discovery. Patch byZachary Ware.
• bpo-16919: test_crypt now works with unittest test discovery. Patch byZachary Ware.
• bpo-16910: test_bytes, test_unicode, and test_userstring now work withunittest test discovery. Patch by Zachary Ware.
• bpo-16905: test_warnings now works with unittest test discovery. Initialpatch by Berker Peksag.
• bpo-16898: test_bufio now works with unittest test discovery. Patch byZachary Ware.
• bpo-16888: test_array now works with unittest test discovery. Patch byZachary Ware.
• bpo-16896: test_asyncore now works with unittest test discovery. Patch byZachary Ware.
• bpo-16897: test_bisect now works with unittest test discovery. Initialpatch by Zachary Ware.
• bpo-16852: test_genericpath, test_posixpath, test_ntpath, and test_macpathnow work with unittest test discovery. Patch by Zachary Ware.
• bpo-16748: test_heapq now works with unittest test discovery.
• bpo-10646: Tests rearranged for os.samefile/samestat to check for not justsymlinks but also hard links.
• bpo-15302: Switch regrtest from using getopt to using argparse.
• bpo-15324: Fix regrtest parsing of –fromfile, –match, and –randomizeoptions.
• bpo-16702: test_urllib2_localnet tests now correctly ignores proxies forlocalhost tests.
• bpo-16664: Add regression tests for glob’s behaviour concerning entriesstarting with a ”.”. Patch by Sebastian Kreft.
• bpo-13390: The-R option to regrtest now also checks for memoryallocation leaks, usingsys.getallocatedblocks().
• bpo-16559: Add more tests for the json module, including some from theofficial test suite at json.org. Patch by Serhiy Storchaka.
• bpo-16661: Fix theos.getgrouplist() test by not assuming that it givesthe same output asid -G.
• bpo-16115: Add some tests for the executable argument tosubprocess.Popen(). Initial patch by Kushal Das.
• bpo-16126: PyErr_Format format mismatch in _testcapimodule.c. Patch bySerhiy Storchaka.
• bpo-15304: Fix warning message whenos.chdir() fails insidetest.support.temp_cwd(). Patch by Chris Jerdonek.
• bpo-15802: Fix test logic inTestMaildir.test_create_tmp(). Patch bySerhiy Storchaka.
• bpo-15557: Added a test suite for the webbrowser module, thanks to AntonBarkovsky.
• bpo-16698: Skip posix test_getgroups when built with OS X deploymenttarget prior to 10.6.

Build¶

• bpo-16067: Add description into MSI file to replace installer’s temporaryname.
• bpo-18257: Fix readlink usage in python-config. Install the pythonversion again on Darwin.
• bpo-18481: Add C coverage reporting with gcov and lcov. A new make target“coverage- report” creates an instrumented Python build, runs unit testsand creates a HTML. The report can be updated with “make coverage-lcov”.
• bpo-17845: Clarified the message printed when some module are not built.
• bpo-18256: Compilation fix for recent AIX releases. Patch by DavidEdelsohn.
• bpo-17547: In configure, explicitly pass -Wformat for the benefit for GCC4.8.
• bpo-15172: Document NASM 2.10+ as requirement for building OpenSSL 1.0.1on Windows.
• bpo-17591: Use lowercase filenames when including Windows header files.Patch by Roumen Petrov.
• bpo-17550: Fix the –enable-profiling configure switch.
• bpo-17425: Build with openssl 1.0.1d on Windows.
• bpo-16754: Fix the incorrect shared library extension on linux. Introducetwo makefile macros SHLIB_SUFFIX and EXT_SUFFIX. SO now has the value ofSHLIB_SUFFIX again (as in 2.x and 3.1). The SO macro is removed in 3.4.
• bpo-5033: Fix building of the sqlite3 extension module when the SQLitelibrary version has “beta” in it. Patch by Andreas Pelme.
• bpo-17228: Fix building without pymalloc.
• bpo-3718: Use AC_ARG_VAR to set MACHDEP in configure.ac.
• bpo-16235: Implement python-config as a shell script.
• bpo-16769: Remove outdated Visual Studio projects.
• bpo-17031: Fix running regen in cross builds.
• bpo-3754: fix typo in pthread AC_CACHE_VAL.
• bpo-15484: Fix _PYTHON_PROJECT_BASE for srcdir != builddir builds; use_PYTHON_PROJECT_BASE in distutils/sysconfig.py.
• Drop support for Windows 2000 (changeset e52df05b496a).
• bpo-17029: Let h2py search the multiarch system include directory.
• bpo-16953: Fix socket module compilation on platforms withHAVE_BROKEN_POLL. Patch by Jeffrey Armstrong.
• bpo-16320: Remove redundant Makefile dependencies for strings and bytes.
• Cross compiling needs host and build settings. configure no longer createsa broken PYTHON_FOR_BUILD variable when –build is missing.
• Fix cross compiling issue in setup.py, ensure that lib_dirs and inc_dirsare defined in cross compiling mode, too.
• bpo-16836: Enable IPv6 support even if IPv6 is disabled on the build host.
• bpo-16593: Have BSD ‘make -s’ do the right thing, thanks to Daniel Shahaf
• bpo-16262: fix out-of-src-tree builds, if mercurial is not installed.
• bpo-15298: ensure _sysconfigdata is generated in build directory, notsource directory.
• bpo-15833: Fix a regression in 3.3 that resulted in exceptions beingraised if importlib failed to write byte-compiled files. This affectedattempts to build Python out-of-tree from a read-only source directory.
• bpo-15923: Fix a mistake inasdl_c.py that resulted in a TypeErrorafter 2801bf875a24 (see #15801).
• bpo-16135: Remove OS/2 support.
• bpo-15819: Make sure we can build Python out-of-tree from a read-onlysource directory. (Somewhat related toissue #9860.)
• bpo-15587: Enable Tk high-resolution text rendering on Macs with Retinadisplays. Applies to Tkinter apps, such as IDLE, on OS X framework buildslinked with Cocoa Tk 8.5.
• bpo-17161: make install now also installs a python3 man page.

C API¶

• bpo-18351: Fix various issues in a function in importlib provided to helpPyImport_ExecCodeModuleWithPathnames() (and thus by extensionPyImport_ExecCodeModule() and PyImport_ExecCodeModuleEx()).
• bpo-9369: The types ofchar* arguments of PyObject_CallFunction() andPyObject_CallMethod() now changed toconstchar*. Based on patches byJörg Müller and Lars Buitinck.
• bpo-17206: Py_CLEAR(), Py_DECREF(), Py_XINCREF() and Py_XDECREF() nowexpand their arguments once instead of multiple times. Patch written byIllia Polosukhin.
• bpo-17522: Add the PyGILState_Check() API.
• bpo-17327: Add PyDict_SetDefault.
• bpo-16881: Fix Py_ARRAY_LENGTH macro for GCC < 3.1.
• bpo-16505: Remove unused Py_TPFLAGS_INT_SUBCLASS.
• bpo-16086: PyTypeObject.tp_flags and PyType_Spec.flags are now unsigned(unsigned long and unsigned int) to avoid an undefined behaviour withPy_TPFLAGS_TYPE_SUBCLASS ((1 << 31). PyType_GetFlags() result type is nowunsigned too (unsigned long, instead of long).
• bpo-16166: Add PY_LITTLE_ENDIAN and PY_BIG_ENDIAN macros and unifiedendianness detection and handling.

Documentation¶

• bpo-17701: Improving strftime documentation.
• bpo-18440: Clarify thathash() can truncate the value returned from anobject’s custom__hash__() method.
• bpo-17844: Add links to encoders and decoders for bytes-to-bytes codecs.
• bpo-14097: improve the “introduction” page of the tutorial.
• bpo-17977: The documentation for the cadefault argument’s default value inurllib.request.urlopen() is fixed to match the code.
• bpo-6696: add documentation for the Profile objects, and improveprofile/cProfile docs. Patch by Tom Pinckney.
• bpo-15940: Specify effect of locale on time functions.
• bpo-17538: Document XML vulnerabilties
• bpo-16642: sched.scheduler timefunc initial default is time.monotonic.Patch by Ramchandra Apte
• bpo-17047: remove doubled words in docs and docstrings reported by SerhiyStorchaka and Matthew Barnett.
• bpo-15465: Document the versioning macros in the C API docs rather thanthe standard library docs. Patch by Kushal Das.
• bpo-16406: Combine the pages for uploading and registering to PyPI.
• bpo-16403: Document how distutils uses the maintainer field in PKG-INFO.Patch by Jyrki Pulliainen.
• bpo-16695: Document how glob handles filenames starting with a dot.Initial patch by Jyrki Pulliainen.
• bpo-8890: Stop advertising an insecure practice by replacing uses of the/tmp directory with better alternatives in the documentation. Patch byGeoff Wilson.
• bpo-17203: add long option names to unittest discovery docs.
• bpo-13094: add “Why do lambdas defined in a loop with different values allreturn the same result?” programming FAQ.
• bpo-14901: Update portions of the Windows FAQ. Patch by Ashish NitinPatil.
• bpo-16267: Better document the 3.3+ approach to combining @abstractmethodwith @staticmethod, @classmethod and @property
• bpo-15209: Clarify exception chaining description in exceptions moduledocumentation
• bpo-15990: Improve argument/parameter documentation.
• bpo-16209: Move the documentation for the str built-in function to a newstr class entry in the “Text Sequence Type” section.
• bpo-13538: Improve str() and object.__str__() documentation.
• bpo-16489: Make it clearer that importlib.find_loader() needs parentpackages to be explicitly imported.
• bpo-16400: Update the description of which versions of a given packagePyPI displays.
• bpo-15677: Document that zlib and gzip accept a compression level of 0 tomean ‘no compression’. Patch by Brian Brazil.
• bpo-16197: Update winreg docstrings and documentation to match code. Patchby Zachary Ware.
• bpo-8040: added a version switcher to the documentation. Patch by YurySelivanov.
• bpo-16241: Document -X faulthandler command line option. Patch by MarekŠuppa.
• Additional comments and some style changes in the concurrent.futures URLretrieval example
• bpo-16115: Improve subprocess.Popen() documentation around args, shell,and executable arguments.
• bpo-13498: Clarify docs of os.makedirs()’s exist_ok argument. Done withgreat native- speaker help from R. David Murray.
• bpo-15533: Clarify docs and add tests forsubprocess.Popen()‘s cwdargument.
• bpo-15979: Improve timeit documentation.
• bpo-16036: Improve documentation of built-inint()‘s signature andarguments.
• bpo-15935: Clarification ofargparse docs, re: add_argument() type anddefault arguments. Patch contributed by Chris Jerdonek.
• bpo-11964: Document a change in v3.2 to the behavior of the indentparameter of json encoding operations.
• bpo-15116: Remove references to appscript as it is no longer beingsupported.

Tools/Demos¶

• bpo-18817: Fix a resource warning in Lib/aifc.py demo. Patch by VajraskyKok.
• bpo-18439: Make patchcheck work on Windows for ACKS, NEWS.
• bpo-18448: Fix a typo in Tools/demo/eiffel.py.
• bpo-18457: Fixed saving of formulas and complex numbers inTools/demo/ss1.py.
• bpo-18449: Make Tools/demo/ss1.py work again on Python 3. Patch by FévryThibault.
• bpo-12990: The “Python Launcher” on OSX could not launch python scriptsthat have paths that include wide characters.
• bpo-15239: Make mkstringprep.py work again on Python 3.
• bpo-17028: Allowed Python arguments to be supplied to the Windowslauncher.
• bpo-17156: pygettext.py now detects the encoding of source files andcorrectly writes and escapes non-ascii characters.
• bpo-15539: Fix a number of bugs in Tools/scripts/pindent.py. Nowpindent.py works with a “with” statement. pindent.py no longer producesimproper indentation. pindent.py now works with continued lines brokenafter “class” or “def” keywords and with continuations at the start ofline.
• bpo-11797: Add a 2to3 fixer that maps reload() to imp.reload().
• bpo-10966: Remove the concept of unexpected skipped tests.
• bpo-9893: Removed the Misc/Vim directory.
• Removed the Misc/TextMate directory.
• bpo-16245: Add the Tools/scripts/parse_html5_entities.py script to parsethe list of HTML5 entities and update the html.entities.html5 dictionary.
• bpo-15378: Fix Tools/unicode/comparecodecs.py. Patch by Serhiy Storchaka.
• bpo-16549: Make json.tool work again on Python 3 and add tests. Initialpatch by Berker Peksag and Serhiy Storchaka.
• bpo-13301: use ast.literal_eval() instead of eval() inTools/i18n/msgfmt.py. Patch by Serhiy Storchaka.

Windows¶

• bpo-18569: The installer now adds .py to the PATHEXT variable whenextensions are registered. Patch by Paul Moore.

Core and Builtins¶

• bpo-16046: Fix loading sourceless legacy .pyo files.
• bpo-16060: Fix refcounting bug when__trunc__() returns an object whose__int__() gives a non-integer. Patch by Serhiy Storchaka.

Library¶

• bpo-16012: Fix a regression in pyexpat. The parser’sUseForeignDTD()method doesn’t require an argument again.

Core and Builtins¶

• bpo-15900: Fix reference leak inPyUnicode_TranslateCharmap().
• bpo-15926: Fix crash after multiple reinitializations of the interpreter.
• bpo-15895: Fix FILE pointer leak in one error branch ofPyRun_SimpleFileExFlags() when filename points to a pyc/pyo file,closeit is false an and set_main_loader() fails.
• Fixes for a few crash and memory leak regressions found by Coverity.

Library¶

• bpo-15882: Change_decimal to accept any coefficient tuple whenconstructing infinities. This is done for backwards compatibility withdecimal.py: Infinity coefficients are undefined in _decimal (in accordancewith the specification).
• bpo-15925: Fix a regression inemail.util where theparsedate() andparsedate_tz() functions did not return None anymore when the argumentcould not be parsed.
• bpo-15973: Fix a segmentation fault when comparing datetime timezoneobjects.
• bpo-15977: Fix memory leak in Modules/_ssl.c when the function_set_npn_protocols() is called multiple times, thanks to DanielSommermann.
• bpo-15969:faulthandler module: rename dump_tracebacks_later() todump_traceback_later() and cancel_dump_tracebacks_later() tocancel_dump_traceback_later().
• _decimal module: use only C 89 style comments.

Core and Builtins¶

• bpo-13992: The trashcan mechanism is now thread-safe. This eliminatessporadic crashes in multi-thread programs when several long deallocatorchains ran concurrently and involved subclasses of built-in containertypes.
• bpo-15784: ModifyOSError.__str__() to better distinguish between errnoerror numbers and Windows error numbers.
• bpo-15781: Fix two small race conditions in import’s module locking.

Library¶

• bpo-17158: Add ‘symbols’ to help() welcome message; clarify ‘modules spam’messages.
• bpo-15847: Fix a regression in argparse, which did not accept tuples asargument lists anymore.
• bpo-15828: Restore support for C extensions inimp.load_module().
• bpo-15340: Fix importing the random module when/dev/urandom cannot beopened. This was a regression caused by the hash randomization patch.
• bpo-10650: Deprecate the watchexp parameter of theDecimal.quantize()method.
• bpo-15785: Modifywindow.get_wch() API of the curses module: return acharacter for most keys, and an integer for special keys, instead ofalways returning an integer. So it is now possible to distinguish specialkeys like keypad keys.
• bpo-14223: Fixwindow.addch() of the curses module for specialcharacters like curses.ACS_HLINE: the Python function addch(int) andaddch(bytes) is now calling the C function waddch()/mvwaddch() (as it wasdone in Python 3.2), instead of wadd_wch()/mvwadd_wch(). The Pythonfunction addch(str) is still calling the C functionwadd_wch()/mvwadd_wch() if the Python curses is linked to libncursesw.

Build¶

• bpo-15822: Really ensure 2to3 grammar pickles are properly installed(replaces fixes forIssue #15645).

Documentation¶

• bpo-15814: The memoryview enhancements in 3.3.0 accidentally permitted thehashing of multi-dimensional memorviews and memoryviews with multi-byteitem formats. The intended restrictions have now been documented - theywill be correctly enforced in 3.3.1.

Core and Builtins¶

• bpo-15573: memoryview comparisons are now performed by value with fullsupport for any valid struct module format definition.
• bpo-15316: When an item in the fromlist for__import__() doesn’t exist,don’t raise an error, but if an exception is raised as part of an importdo let that propagate.
• bpo-15778: Ensure thatstr(ImportError(msg)) returns a str even whenmsg isn’t a str.
• bpo-2051: Source file permission bits are once again correctly copied tothe cached bytecode file. (The migration to importlib reintroduced thisproblem because these was no regression test. A test has been added aspart of this patch)
• bpo-15761: Fix crash whenPYTHONEXECUTABLE is set on Mac OS X.
• bpo-15726: Fix incorrect bounds checking in PyState_FindModule. Patch byRobin Schreiber.
• bpo-15604: Update uses ofPyObject_IsTrue() to check for and handleerrors correctly. Patch by Serhiy Storchaka.
• bpo-14846:importlib.FileFinder now handles the case where the directorybeing searched is removed after a previous import attempt.

Library¶

• bpo-13370: Ensure that ctypes works on Mac OS X when Python is compiledusing the clang compiler.
• bpo-13072: The array module’s ‘u’ format code is now deprecated and willbe removed in Python 4.0.
• bpo-15544: Fix Decimal.__float__ to work with payload-carrying NaNs.
• bpo-15776: Allow pyvenv to work in existing directory with –clean.
• bpo-15249: email’s BytesGenerator now correctly mangles From lines (whenrequested) even if the body contains undecodable bytes.
• bpo-15777: Fix a refleak in _posixsubprocess.
• bpo-665194: Updateemail.utils.localtime to use datetime.astimezone andcorrectly handle historic changes in UTC offsets.
• bpo-15199: Fix JavaScript’s default MIME type to application/javascript.Patch by Bohuslav Kabrda.
• bpo-12643:code.InteractiveConsole now respectssys.excepthook whendisplaying exceptions. Patch by Aaron Iles.
• bpo-13579:string.Formatter now understands the ‘a’ conversionspecifier.
• bpo-15595: Fixsubprocess.Popen(universal_newlines=True) for certainlocales (utf-16 and utf-32 family). Patch by Chris Jerdonek.
• bpo-15477: In cmath and math modules, add workaround for platforms whosesystem- supplied log1p function doesn’t respect signs of zeros.
• bpo-15715:importlib.__import__() will silence an ImportError when theuse of fromlist leads to a failed import.
• bpo-14669: Fix pickling of connections and sockets on Mac OS X bysending/receiving an acknowledgment after file descriptor transfer.TestPicklingConnection has been reenabled for Mac OS X.
• bpo-11062: Fix adding a message from file to Babyl mailbox.
• bpo-15646: Prevent equivalent of a fork bomb when usingmultiprocessingon Windows without theif__name__=='__main__' idiom.

IDLE¶

• bpo-15678: Fix IDLE menus when started from OS X command line (3.3.0b2regression).

Documentation¶

• Touched up the Python 2 to 3 porting guide.
• bpo-14674: Add a discussion of thejson module’s standard compliance.Patch by Chris Rebert.
• Create a ‘Concurrent Execution’ section in the docs, and split up the‘Optional Operating System Services’ section to use a more user-centricclassification scheme (splitting them across the new CE section, IPC andtext processing). Operating system limitations can be reflected with theSphinx:platform: tag, it doesn’t make sense as part of the Table ofContents.
• bpo-4966: Bring the sequence docs up to date for the Py3k transition andthe many language enhancements since they were original written.
• The “path importer” misnomer has been replaced with Eric Snow’s more-awkward-but-at-least-not-wrong suggestion of “path based finder” in theimport system reference docs.
• bpo-15640: Documentimportlib.abc.Finder as deprecated.
• bpo-15630: Add an example for “continue” stmt in the tutorial. Patch byDaniel Ellis.

Tests¶

• bpo-15747: ZFS always returns EOPNOTSUPP when attempting to set theUF_IMMUTABLE flag (via either chflags or lchflags); refactor affectedtests in test_posix.py to account for this.
• bpo-15285: Refactor the approach for testing connect timeouts using twoexternal hosts that have been configured specifically for this type oftest.
• bpo-15743: Remove the deprecated method usage inurllib tests. Patch byJeff Knupp.
• bpo-15615: Add some tests for thejson module’s handling of invalidinput data. Patch by Kushal Das.

Build¶

• Output lib files for PGO build into PGO directory.
• Pick up 32-bit launcher from PGO directory on 64-bit PGO build.
• DropPC\python_nt.h as it’s not used. Add input dependency on custombuild step.
• bpo-15511: Drop explicit dependency on pythonxy.lib from _decimal amd64configuration.
• Add missing PGI/PGO configurations for pywlauncher.
• bpo-15645: Ensure 2to3 grammar pickles are properly installed.

Core and Builtins¶

• bpo-15568: Fix the return value ofyieldfrom when StopIteration israised by a custom iterator.
• bpo-13119:sys.stdout andsys.stderr are now using “rn” newline onWindows, as Python 2.
• bpo-15534: Fix the fast-search function for non-ASCII Unicode strings.
• bpo-15508: Fix the docstring for__import__() to have the proper defaultvalue of 0 for ‘level’ and to not mention negative levels since they arenot supported.
• bpo-15425: Eliminated traceback noise from more situations involvingimportlib.
• bpo-14578: Support modules registered in the Windows registry again.
• bpo-15466: Stop using TYPE_INT64 in marshal, to make importlib.h (andother byte code files) equal between 32-bit and 64-bit systems.
• bpo-1692335: Move initial exception args assignment toBaseException.__new__() to help pickling of naive subclasses.
• bpo-12834: FixPyBuffer_ToContiguous() for non-contiguous arrays.
• bpo-15456: Fix code__sizeof__() after #12399 change. Patch by SerhiyStorchaka.
• bpo-15404: Refleak in PyMethodObject repr.
• bpo-15394: An issue inPyModule_Create() that caused references to beleaked on some error paths has been fixed. Patch by Julia Lawall.
• bpo-15368: An issue that caused bytecode generation to benon-deterministic has been fixed.
• bpo-15202: Consistently use the name “follow_symlinks” for new parametersin os and shutil functions.
• bpo-15314:__main__.__loader__ is now set correctly during interpreterstartup.
• bpo-15111: When a module imported using ‘from import’ has an ImportErrorinside itself, don’t mask that fact behind a generic ImportError for themodule itself.
• bpo-15293: Add GC support to the AST base node type.
• bpo-15291: Fix a memory leak where AST nodes where not properlydeallocated.
• bpo-15110: Fix the tracebacks generated by “import xxx” to not show theimportlib stack frames.
• bpo-16369: Global PyTypeObjects not initialized with PyType_Ready(...).
• bpo-15020: The program name used to search for Python’s path is now“python3” under Unix, not “python”.
• bpo-15897: zipimport.c doesn’t check return value of fseek(). Patch byFelipe Cruz.
• bpo-15033: Fix the exit status bug when modules invoked using -m switch,return the proper failure return value (1). Patch contributed by JeffKnupp.
• bpo-15229: AnOSError subclass whose __init__ doesn’t call backOSError.__init__ could produce incomplete instances, leading to crasheswhen calling str() on them.
• bpo-15307: Virtual environments now use symlinks with framework builds onMac OS X, like other POSIX builds.

Library¶

• bpo-14590: configparser now correctly strips inline comments whendelimiter occurs earlier without preceding space.
• bpo-15424: Add a__sizeof__() implementation for array objects. Patchby Ludwig Hähne.
• bpo-15576: Allow extension modules to act as a package’s __init__ module.
• bpo-15502: Haveimportlib.invalidate_caches() work onsys.meta_pathinstead ofsys.path_importer_cache.
• bpo-15163: Pydoc shouldn’t list __loader__ as module data.
• bpo-15471: Do not use mutable objects as defaults forimportlib.__import__().
• bpo-15559: To avoid a problematic failure mode when passed to the bytesconstructor, objects in the ipaddress module no longer implement__index__() (they still implement__int__() as appropriate).
• bpo-15546: Fix handling of pathological input data in the peek() andread1() methods of the BZ2File, GzipFile and LZMAFile classes.
• bpo-12655: Instead of requiring a custom type,os.sched_getaffinity()andos.sched_setaffinity() now use regular sets of integers to representthe CPUs a process is restricted to.
• bpo-15538: Fix compilation of thesocket.getnameinfo() /socket.getaddrinfo() emulation code. Patch by Philipp Hagemeister.
• bpo-15519: Properly expose WindowsRegistryFinder in importlib (and use thecorrect term for it). Original patch by Eric Snow.
• bpo-15502: Bring the importlib ABCs into line with the current state ofthe import protocols given PEP 420. Original patch by Eric Snow.
• bpo-15499: Launching a webbrowser in Unix used to sleep for a few seconds.Original patch by Anton Barkovsky.
• bpo-15463: The faulthandler module truncates strings to 500 characters,instead of 100, to be able to display long file paths.
• bpo-6056: Makemultiprocessing use setblocking(True) on the sockets ituses. Original patch by J Derek Wilson.
• bpo-15364: Fix sysconfig.get_config_var(‘srcdir’) to be an absolute path.
• bpo-15413:os.times() had disappeared under Windows.
• bpo-15402: An issue in the struct module that causedsys.getsizeof() toreturn incorrect results for struct.Struct instances has been fixed.Initial patch by Serhiy Storchaka.
• bpo-15232: When mangle_from is True,email.Generator now correctlymangles lines that start with ‘From ‘ that occur in a MIME preamble orepilogue.
• bpo-15094: Incorrectly placed #endif in _tkinter.c. Patch by SerhiyStorchaka.
• bpo-13922:argparse no longer incorrectly strips ‘–’s that appear afterthe first one.
• bpo-12353:argparse now correctly handles null argument values.
• bpo-10017: Fix TypeError using pprint on dictionaries with user-definedtypes as keys or other unorderable keys. (See also: bpo-14998)
• bpo-15397:inspect.getmodulename() is now based directly on importlibvia a newimportlib.machinery.all_suffixes() API.
• bpo-14635:telnetlib will use poll() rather than select() when possibleto avoid failing due to the select() file descriptor limit.
• bpo-15180: Clarify posixpath.join() error message when mixing str & bytes.
• bpo-15343: pkgutil now includes an iter_importer_modules implementationfor importlib.machinery.FileFinder (similar to the way it already handledzipimport.zipimporter).
• bpo-15314: runpy now sets __main__.__loader__ correctly.
• bpo-15357: The import emulation in pkgutil is now deprecated. pkgutil usesimportlib internally rather than the emulation.
• bpo-15233: Python now guarantees that callables registered with the atexitmodule will be called in a deterministic order.
• bpo-15238:shutil.copystat() now copies Linux “extended attributes”.
• bpo-15230: runpy.run_path now correctly sets __package__ as described inthe documentation.
• bpo-15315: Support VS 2010 in distutils cygwincompiler.
• bpo-15294: Fix a regression in pkgutil.extend_path()’s handling of nestednamespace packages.
• bpo-15056:imp.cache_from_source() andimp.source_from_cache() raiseNotImplementedError whensys.implementation.cache_tag is set to None.
• bpo-15256: Grammatical mistake in exception raised byimp.find_module().
• bpo-5931:wsgiref environ variable SERVER_SOFTWARE will specify animplementation specific term like CPython, Jython instead of generic“Python”.
• bpo-13248: Remove obsolete argument “max_buffer_size” of BufferedWriterand BufferedRWPair, from the io module.
• bpo-13248: Remove obsolete argument “version” ofargparse.ArgumentParser.
• bpo-14814: Implement more consistent ordering and sorting behaviour foripaddress objects.
• bpo-14814:ipaddress network objects correctly return NotImplementedwhen compared to arbitrary objects instead of raising TypeError.
• bpo-14990: Correctly fail with SyntaxError on invalid encodingdeclaration.
• bpo-14814:ipaddress now provides more informative error messages whenconstructing instances directly (changes permitted during beta due toprovisional API status).
• bpo-15247:io.FileIO now raises an error when given a file descriptorpointing to a directory.
• bpo-15261: Stop os.stat(fd) crashing on Windows when fd not open.
• bpo-15166: Implementimp.get_tag() usingsys.implementation.cache_tag.
• bpo-15210: Catch KeyError whenimportlib.__init__() can’t find_frozen_importlib in sys.modules, not ImportError.
• bpo-15030:importlib.abc.PyPycLoader now supports the new source sizeheader field in .pyc files.
• bpo-5346: Preserve permissions of mbox, MMDF and Babyl mailbox files onflush().
• bpo-10571: Fix the “–sign” option of distutils’ upload command. Patch byJakub Wilk.
• bpo-9559: If messages were only added, a new file is no longer created andrenamed over the old file when flush() is called on an mbox, MMDF or Babylmailbox.
• bpo-10924: Fixedcrypt.mksalt() to use a RNG that is suitable forcryptographic purpose.
• bpo-15184: Ensure consistent results of OS X configuration tailoring foruniversal builds by factoring out common OS X-specific customizations fromsysconfig, distutils.sysconfig, distutils.util, anddistutils.unixccompiler into a new module _osx_support.

C API¶

• bpo-15610:PyImport_ImportModuleEx() now uses a ‘level’ of 0 instead of-1.
• bpo-15169: Strip out the C implementation ofimp.source_from_cache()used by PyImport_ExecCodeModuleWithPathnames() and used the Python codeinstead. Leads to PyImport_ExecCodeModuleObject() to not try to infer thesource path from the bytecode path asPyImport_ExecCodeModuleWithPathnames() does. (See also: bpo-14599)

Library¶

• bpo-6493: An issue in ctypes on Windows that caused structure bitfields oftypectypes.c_uint32 and width 32 to incorrectly be set has been fixed.
• bpo-15194: Update libffi to the 3.0.11 release.

IDLE¶

• bpo-13052: Fix IDLE crashing when replace string in Search/Replace dialogended with\. Patch by Roger Serwy.

Tools/Demos¶

• bpo-15458: python-config gets a new option –configdir to print the $LIBPLvalue.
• Move importlib.test.benchmark to Tools/importbench.
• bpo-12605: The gdb hooks for debugging CPython (within Tools/gdb) havebeen enhanced to show information on more C frames relevant to CPythonwithin the “py-bt” and “py-bt-full” commands:
  • C frames that are waiting on the GIL
  • C frames that are garbage-collecting
  • C frames that are due to the invocation of a PyCFunction

Documentation¶

• bpo-15041: Update “see also” list in tkinter documentation.
• bpo-15444: Use proper spelling for non-ASCII contributor names. Patch bySerhiy Storchaka.
• bpo-15295: Reorganize and rewrite the documentation on the import system.
• bpo-15230: Clearly document some of the limitations of the runpy moduleand nudge readers towards importlib when appropriate.
• bpo-15053: Copy Python 3.3 import lock change notice to all relevantfunctions in imp instead of just at the top of the relevant section.
• bpo-15288: Link to the term “loader” in notes in pkgutil about how thingswon’t work as expected in Python 3.3 and mark the requisite functions as“changed” since they will no longer work with modules directly imported byimport itself.
• bpo-13557: Clarify effect of giving two different namespaces toexec()orexecfile().
• bpo-15250: Document thatfilecmp.dircmp() compares files shallowly.Patch contributed by Chris Jerdonek.
• bpo-15442: Expose the default list of directories ignored byfilecmp.dircmp() as a module attribute, and expand the list to moremodern values.

Tests¶

• bpo-15467: Move helpers for__sizeof__() tests into test_support. Patchby Serhiy Storchaka.
• bpo-15320: Make iterating the list of tests thread-safe when running testsin multiprocess mode. Patch by Chris Jerdonek.
• bpo-15168: Moveimportlib.test totest.test_importlib.
• bpo-15091: Reactivate a test on UNIX which was failing thanks to aforgottenimportlib.invalidate_caches() call.
• bpo-15230: Adopted a more systematic approach in the runpy tests.
• bpo-15300: Ensure the temporary test working directories are in the sameparent folder when running tests in multiprocess mode from a Python build.Patch by Chris Jerdonek.
• bpo-15284: Skip {send,recv}msg tests in test_socket when IPv6 is notenabled. Patch by Brian Brazil.
• bpo-15277: Fix a resource leak in support.py when IPv6 is disabled. Patchby Brian Brazil.

Build¶

• bpo-11715: Fix multiarch detection without having Debian development tools(dpkg-dev) installed.
• bpo-15037: Build OS X installers with local copy of ncurses 5.9 librariesto avoid curses.unget_wch bug present in older versions of ncurses such asthose shipped with OS X.
• bpo-15560: Fix building _sqlite3 extension on OS X with an SDK. Also, forOS X installers, ensure consistent sqlite3 behavior and featureavailability by building a local copy of libsqlite3 rather than dependingon the wide range of versions supplied with various OS X releases.
• bpo-8847: Disable COMDAT folding in Windows PGO builds.
• bpo-14018: Fix OS X Tcl/Tk framework checking when using OS X SDKs.
• bpo-16256: OS X installer now sets correct permissions for doc directory.
• bpo-15431: Add _freeze_importlib project to regenerate importlib.h onWindows. Patch by Kristján Valur Jónsson.
• bpo-14197: For OS X framework builds, ensure links to the shared libraryare created with the proper ABI suffix.
• bpo-14330: For cross builds, don’t use host python, use host search pathsfor host compiler.
• bpo-15235: Allow Berkley DB versions up to 5.3 to build the dbm module.
• bpo-15268: Search curses.h in /usr/include/ncursesw.

Core and Builtins¶

• Fix a (most likely) very rare memory leak when calling main() and notbeing able to decode a command-line argument.
• bpo-14815: Use Py_ssize_t instead of long for the object hash, to preserveall 64 bits of hash on Win64.
• bpo-12268: File readline, readlines and read() or readall() methods nolonger lose data when an underlying read system call is interrupted.IOError is no longer raised due to a read system call returning EINTR fromwithin these methods.
• bpo-11626: Add _SizeT functions to stable ABI.
• bpo-15142: Fix reference leak when deallocating instances of types createdusing PyType_FromSpec().
• bpo-10053: Don’t close FDs when FileIO.__init__ fails. Loosely based onthe work by Hirokazu Yamamoto.
• bpo-15096: Removed support for ur’’ as the raw notation isn’t compatiblewith Python 2.x’s raw unicode strings.
• bpo-13783: Generator objects now use the identifier APIs internally
• bpo-14874: Restore charmap decoding speed to pre-PEP 393 levels. Patch bySerhiy Storchaka.
• bpo-15026: utf-16 encoding is now significantly faster (up to 10x). Patchby Serhiy Storchaka.
• bpo-11022: open() and io.TextIOWrapper are now callinglocale.getpreferredencoding(False) instead oflocale.getpreferredencoding() in text mode if the encoding is notspecified. Don’t change temporary the locale encoding usinglocale.setlocale(), use the current locale encoding instead of the userpreferred encoding.
• bpo-14673: Add Eric Snow’s sys.implementation implementation.
• bpo-15038: Optimize python Locks on Windows.

Library¶

• bpo-12288: Consider ‘0’ and ‘0.0’ as valid initialvalue for tkinterSimpleDialog.
• bpo-15512: Add a __sizeof__ implementation for parser. Patch by SerhiyStorchaka.
• bpo-15469: Add a __sizeof__ implementation for deque objects. Patch bySerhiy Storchaka.
• bpo-15489: Add a __sizeof__ implementation for BytesIO objects. Patch bySerhiy Storchaka.
• bpo-15487: Add a __sizeof__ implementation for buffered I/O objects. Patchby Serhiy Storchaka.
• bpo-15514: Correct __sizeof__ support for cpu_set. Patch by SerhiyStorchaka.
• bpo-15177: Added dir_fd parameter to os.fwalk().
• bpo-15061: Re-implemented hmac.compare_digest() in C to prevent furthertiming analysis and to support all buffer protocol aware objects as wellas ASCII only str instances safely.
• bpo-15164: Change return value of platform.uname() from a plain tuple to acollections.namedtuple.
• Support Mageia Linux in the platform module.
• bpo-11678: Support Arch linux in the platform module.
• bpo-15118: Change return value of os.uname() and os.times() from plaintuples to immutable iterable objects with named attributes (structseqobjects).
• Speed up _decimal by another 10-15% by caching the thread local contextthat was last accessed. In the pi benchmark (64-bit platform, prec=9),_decimal is now only 1.5x slower than float.
• Remove the packaging module, which is not ready for prime time.
• bpo-15154: Add “dir_fd” parameter to os.rmdir, remove “rmdir” parameterfrom os.remove / os.unlink.
• bpo-4489: Add a shutil.rmtree that isn’t susceptible to symlink attacks.It is used automatically on platforms supporting the necessary os.openat()and os.unlinkat() functions. Main code by Martin von Löwis.
• bpo-15156: HTMLParser now uses the new “html.entities.html5” dictionary.
• bpo-11113: add a new “html5” dictionary containing the named characterreferences defined by the HTML5 standard and the equivalent Unicodecharacter(s) to the html.entities module.
• bpo-15114: the strict mode of HTMLParser and the HTMLParseError exceptionare deprecated now that the parser is able to parse invalid markup.
• bpo-3665: u and U escapes are now supported in unicode regularexpressions. Patch by Serhiy Storchaka.
• bpo-15153: Added inspect.getgeneratorlocals to simplify white box testingof generator state updates
• bpo-13062: Added inspect.getclosurevars to simplify testing statefulclosures
• bpo-11024: Fixes and additional tests for Time2Internaldate.
• bpo-14626: Large refactoring of functions / parameters in the os module.Many functions now support “dir_fd” and “follow_symlinks” parameters; somealso support accepting an open file descriptor in place of a path string.Added os.support_* collections as LBYL helpers. Removed many functionsonly previously seen in 3.3 alpha releases (often starting with “f” or“l”, or ending with “at”). Originally suggested by Serhiy Storchaka;implemented by Larry Hastings.
• bpo-15008: Implement PEP 362 “Signature Objects”. Patch by Yury Selivanov.
• bpo-15138: base64.urlsafe_{en,de}code() are now 3-4x faster.
• bpo-444582: Add shutil.which, for finding programs on the system path.Original patch by Erik Demaine, with later iterations by Jan Killian andBrian Curtin.
• bpo-14837: SSL errors now havelibrary andreason attributesdescribing precisely what happened and in which OpenSSL submodule. Thestr() of a SSLError is also enhanced accordingly.
• bpo-9527: datetime.astimezone() method will now supply a class timezoneinstance corresponding to the system local timezone when called with noarguments.
• bpo-14653: email.utils.mktime_tz() no longer relies on system mktime()when timezone offest is supplied.
• bpo-14684: zlib.compressobj() and zlib.decompressobj() now support the useof predefined compression dictionaries. Original patch by Sam Rushing.
• Fix GzipFile’s handling of filenames given as bytes objects.
• bpo-14772: Return destination values from some shutil functions.
• bpo-15064: Implement context manager protocol for multiprocessing types
• bpo-15101: Make pool finalizer avoid joining current thread.
• bpo-14657: The frozen instance of importlib used for bootstrap is now alsothe module imported as importlib._bootstrap.
• bpo-14055: Add __sizeof__ support to _elementtree.
• bpo-15054: A bug in tokenize.tokenize that caused string literals with ‘b’prefixes to be incorrectly tokenized has been fixed. Patch by SerhiyStorchaka.
• bpo-15006: Allow equality comparison between naive and aware time ordatetime objects.
• bpo-15036: Mailbox no longer throws an error if a flush is done betweenoperations when removing or changing multiple items in mbox, MMDF, orBabyl mailboxes.
• bpo-14059: Implement multiprocessing.Barrier.
• bpo-15061: The inappropriately named hmac.secure_compare has been renamedto hmac.compare_digest, restricted to operating on bytes inputs only andhad its documentation updated to more accurately reflect both its intentand its limitations
• bpo-13841: Make child processes exit using sys.exit() on Windows.
• bpo-14936: curses_panel was converted to PEP 3121 and PEP 384 API. Patchby Robin Schreiber.
• bpo-1667546: On platforms supporting tm_zone and tm_gmtoff fields instruct tm, time.struct_time objects returned by time.gmtime(),time.localtime() and time.strptime() functions now have tm_zone andtm_gmtoff attributes. Original patch by Paul Boddie.
• Rename adjusted attribute to adjustable in time.get_clock_info() result.
• bpo-3518: Remove references to non-existent BaseManager.from_address()method.
• bpo-13857: Added textwrap.indent() function (initial patch by Ezra Berch)
• bpo-2736: Added datetime.timestamp() method.
• bpo-13854: Make multiprocessing properly handle non-integer non-stringargument to SystemExit.
• bpo-12157: Make pool.map() empty iterables correctly. Initial patch bymouad.
• bpo-11823: disassembly now shows argument counts on calls with keywordargs.
• bpo-14711: os.stat_float_times() has been deprecated.
• LZMAFile now accepts the modes “rb”/”wb”/”ab” as synonyms of “r”/”w”/”a”.
• The bz2 and lzma modules now each contain an open() function, allowingcompressed files to readily be opened in text mode as well as binary mode.
• BZ2File.__init__() and LZMAFile.__init__() now accept a file object astheir first argument, rather than requiring a separate “fileobj” argument.
• gzip.open() now accepts file objects as well as filenames.
• bpo-14992: os.makedirs(path, exist_ok=True) would raise an OSError whenthe path existed and had the S_ISGID mode bit set when it was notexplicitly asked for. This is no longer an exception as mkdir cannotcontrol if the OS sets that bit for it or not.
• bpo-14989: Make the CGI enable option to http.server available via commandline.
• bpo-14987: Add a missing import statement to inspect.
• bpo-1079: email.header.decode_header now correctly parses all the examplesin RFC2047. There is a necessary visible behavior change: the leadingand/or trailing whitespace on ASCII parts is now preserved.
• bpo-14969: Better handling of exception chaining in contextlib.ExitStack
• bpo-14963: Convert contextlib.ExitStack.__exit__ to use an iterativealgorithm (Patch by Alon Horev)
• bpo-14785: Add sys._debugmallocstats() to help debug low-level memoryallocation issues
• bpo-14443: Ensure that .py files are byte-compiled with the correct Pythonexecutable within bdist_rpm even on older versions of RPM

C API¶

• bpo-15146: Add PyType_FromSpecWithBases. Patch by Robin Schreiber.
• bpo-15042: Add PyState_AddModule and PyState_RemoveModule. Add versionguard for Py_LIMITED_API additions. Patch by Robin Schreiber.
• bpo-13783: Inadvertent additions to the public C API in the PEP 380implementation have either been removed or marked as private interfaces.

Library¶

• bpo-15000: Support the “unique” x32 architecture in _posixsubprocess.c.

IDLE¶

• bpo-9803: Don’t close IDLE on saving if breakpoint is open. Patch by RogerSerwy.
• bpo-14962: Update text coloring in IDLE shell window after changingoptions. Patch by Roger Serwy.

Documentation¶

• bpo-15176: Clarified behavior, documentation, and implementation ofos.listdir().
• bpo-14982: Document that pkgutil’s iteration functions require thenon-standard iter_modules() method to be defined by an importer (somethingthe importlib importers do not define).
• bpo-15081: Document PyState_FindModule. Patch by Robin Schreiber.
• bpo-14814: Added first draft of ipaddress module API reference

Tests¶

• bpo-15187: Bugfix: remove temporary directories test_shutil was leavingbehind.
• bpo-14769: test_capi now has SkipitemTest, which cleverly checks for“parity” between PyArg_ParseTuple() and the Python/getargs.c staticfunction skipitem() for all possible “format units”.
• test_nntplib now tolerates being run from behind NNTP gateways that add“X-Antivirus” headers to articles
• bpo-15043: test_gdb is now skipped entirely if gdb security settings blockloading of the gdb hooks
• bpo-14963: Add test cases for exception handling behaviour incontextlib.ExitStack (Initial patch by Alon Horev)

Build¶

• bpo-13590: Improve support for OS X Xcode 4: * Try to avoid buildingPython or extension modules with problematic llvm-gcc compiler. *Since Xcode 4 removes ppc support, extension module builds now checkfor ppc compiler support and automatically remove ppc and ppc64 archswhen not available. * Since Xcode 4 no longer install SDKs in defaultlocations, extension module builds now revert to using installedheaders and libs if the SDK used to build the interpreter is notavailable. * Update ./configure to use better defaults for universalbuilds; in particular, –enable- universalsdk=yes uses the Xcodedefault SDK and –with-universal-archs now defaults to “intel” if ppcnot available.
• bpo-14225: Fix Unicode support for curses (#12567) on OS X
• bpo-14928: Fix importlib bootstrap issues by using a custom executable(Modules/_freeze_importlib) to build Python/importlib.h.

Core and Builtins¶

• bpo-14835: Make plistlib output empty arrays & dicts like OS X. Patch bySidney San Martín.
• bpo-14744: Use the new _PyUnicodeWriter internal API to speed up str%argsand str.format(args).
• bpo-14930: Make memoryview objects weakrefable.
• bpo-14775: Fix a potential quadratic dict build-up due to the garbagecollector repeatedly trying to untrack dicts.
• bpo-14857: fix regression in references to PEP 3135 implicit __class__closure variable (Reopensissue #12370)
• bpo-14712: Virtual environments. Implemented by Vinay Sajip. (See also:PEP 405)
• bpo-14660: Namespace packages. Implemented by Eric Smith. (See also: PEP420)
• bpo-14494: Fix __future__.py and its documentation to note that absoluteimports are the default behavior in 3.0 instead of 2.7. Patch by SvenMarnach.
• bpo-9260: A finer-grained import lock. Most of the import sequence nowuses per- module locks rather than the global import lock, eliminatingwell-known issues with threads and imports.
• bpo-14624: UTF-16 decoding is now 3x to 4x faster on various inputs. Patchby Serhiy Storchaka.
• asdl_seq and asdl_int_seq are now Py_ssize_t sized.
• bpo-14133: Implement suppression of __context__ display with an attributeon BaseException. This replaces the original mechanism of PEP 409. (Seealso: PEP 415)
• bpo-14417: Mutating a dict during lookup now restarts the lookup insteadof raising a RuntimeError (undoesissue #14205).
• bpo-14738: Speed-up UTF-8 decoding on non-ASCII data. Patch by SerhiyStorchaka.
• bpo-14700: Fix two broken and undefined-behaviour-inducing overflow checksin old-style string formatting.

Library¶

• bpo-14690: Use monotonic clock instead of system clock in the sched,subprocess and trace modules.
• bpo-14443: Tell rpmbuild to use the correct version of Python inbdist_rpm. Initial patch by Ross Lagerwall.
• bpo-12515: email now registers a defect if it gets to EOF while parsing aMIME part without seeing the closing MIME boundary.
• bpo-1672568: email now always decodes base64 payloads, adding padding andignoring non- base64-alphabet characters if needed, and registeringdefects for any such problems.
• bpo-14925: email now registers a defect when the parser decides that thereis a missing header/body separator line. MalformedHeaderDefect, which theexisting code would never actually generate, is deprecated.
• bpo-10365: File open dialog now works instead of crashing even when theparent window is closed before the dialog. Patch by Roger Serwy.
• bpo-8739: Updated smtpd to support RFC 5321, and added support for the RFC1870 SIZE extension.
• bpo-665194: Added a localtime function to email.utils to provide an awarelocal datetime for use in setting Date headers.
• bpo-12586: Added new provisional policies that implement convenientunicode support for email headers. See What’s New for details.
• bpo-14731: Refactored email Policy framework to support full backwardcompatibility with Python 3.2 by default yet allow for the introduction ofnew features through new policies. Note that Policy.must_be_7bit isrenamed to cte_type.
• bpo-14876: Use user-selected font for highlight configuration.
• bpo-14920: Fix the help(urllib.parse) failure on locale C on terminals.Have ascii characters in help.
• bpo-14548: Make multiprocessing finalizers check pid before running tocope with possibility of gc running just after fork.
• bpo-14036: Add an additional check to validate that port in urlparse doesnot go in illegal range and returns None.
• bpo-14862: Add missing names to os.__all__
• bpo-14875: Use float(‘inf’) instead of float(‘1e66666’) in the jsonmodule.
• bpo-13585: Added contextlib.ExitStack
• PEP 3144,Issue #14814: Added the ipaddress module
• bpo-14426: Correct the Date format in Expires attribute of Set-CookieHeader in Cookie.py.
• bpo-14588: The types module now provide new_class() and prepare_class()functions to support PEP 3115 compliant dynamic class creation. Patch byDaniel Urban and Nick Coghlan.
• bpo-13152: Allow to specify a custom tabsize for expanding tabs intextwrap. Patch by John Feuerstein.
• bpo-14721: Send the correct ‘Content-length: 0’ header when the body is anempty string ‘’. Initial Patch contributed by Arve Knudsen.
• bpo-14072: Fix parsing of ‘tel’ URIs in urlparse by making the check forports stricter.
• bpo-9374: Generic parsing of query and fragment portions of url for anyscheme. Supported both by RFC3986 and RFC2396.
• bpo-14798: Fix the functions in pyclbr to raise an ImportError when thefirst part of a dotted name is not a package. Patch by Xavier de Gaye.
• bpo-12098: multiprocessing on Windows now starts child processes using thesame sys.flags as the current process. Initial patch by Sergey Mezentsev.
• bpo-13031: Small speed-up for tarfile when unzipping tarfiles. Patch byJustin Peel.
• bpo-14780: urllib.request.urlopen() now has acadefault argument touse the default certificate store. Initial patch by James Oakley.
• bpo-14829: Fix bisect and range() indexing with large indices (>= 2 ** 32)under 64-bit Windows.
• bpo-14732: The _csv module now uses PEP 3121 module initialization. Patchby Robin Schreiber.
• bpo-14809: Add HTTP status codes introduced by RFC 6585 to http.server andhttp.client. Patch by EungJun Yi.
• bpo-14777: tkinter may return undecoded UTF-8 bytes as a string whenaccessing the Tk clipboard. Modify clipboad_get() to first request typeUTF8_STRING when no specific type is requested in an X11 windowingenvironment, falling back to the current default type STRING if thatfails. Original patch by Thomas Kluyver.
• bpo-14773: Fix os.fwalk() failing on dangling symlinks.
• bpo-12541: Be lenient with quotes around Realm field of HTTP BasicAuthentation in urllib2.
• bpo-14807: move undocumented tarfile.filemode() to stat.filemode() and adddoc entry. Add tarfile.filemode alias with deprecation warning.
• bpo-13815: TarFile.extractfile() now returns io.BufferedReader objects.
• bpo-14532: Add a secure_compare() helper to the hmac module, to mitigatetiming attacks. Patch by Jon Oberheide.
• Add importlib.util.resolve_name().
• bpo-14366: Support lzma compression in zip files. Patch by SerhiyStorchaka.
• bpo-13959: Introduce importlib.find_loader() and documentimp.find_module/load_module as deprecated.
• bpo-14082: shutil.copy2() now copies extended attributes, if possible.Patch by Hynek Schlawack.
• bpo-13959: Make importlib.abc.FileLoader.load_module()/get_filename() andimportlib.machinery.ExtensionFileLoader.load_module() have their singleargument be optional. Allows for the replacement (and thus deprecation) ofimp.load_source()/load_package()/load_compiled().
• bpo-13959: imp.get_suffixes() has been deprecated in favour of the newattributes on importlib.machinery: SOURCE_SUFFIXES,DEBUG_BYTECODE_SUFFIXES, OPTIMIZED_BYTECODE_SUFFIXES, BYTECODE_SUFFIXES,and EXTENSION_SUFFIXES. This led to an indirect deprecation ofinspect.getmoduleinfo().
• bpo-14662: Prevent shutil failures on OS X when destination does notsupport chflag operations. Patch by Hynek Schlawack.
• bpo-14157: Fix time.strptime failing without a year on February 29th.Patch by Hynek Schlawack.
• bpo-14753: Make multiprocessing’s handling of negative timeouts the sameas it was in Python 3.2.
• bpo-14583: Fix importlib bug when a package’s __init__.py would firstimport one of its modules then raise an error.
• bpo-14741: Fix missing support for Ellipsis (‘...’) in parser module.
• bpo-14697: Fix missing support for set displays and set comprehensions inparser module.
• bpo-14701: Fix missing support for ‘raise ... from’ in parser module.
• Add support for timeouts to the acquire() methods of multiprocessing’slock/semaphore/condition proxies.
• bpo-13989: Add support for text mode to gzip.open().
• bpo-14127: The os.stat() result object now provides three additionalfields: st_ctime_ns, st_mtime_ns, and st_atime_ns, providing those timesas an integer with nanosecond resolution. The functions os.utime(),os.lutimes(), and os.futimes() now accept a new parameter, ns, whichaccepts mtime and atime as integers with nanosecond resolution.
• bpo-14127: shutil.copystat now preserves exact mtime and atime onfilesystems providing nanosecond resolution. (See also: bpo-10148)

IDLE¶

• bpo-14958: Change IDLE systax highlighting to recognize all string andbyte literals supported in Python 3.3.
• bpo-10997: Prevent a duplicate entry in IDLE’s “Recent Files” menu.
• bpo-14929: Stop IDLE 3.x from closing on Unicode decode errors whengrepping. Patch by Roger Serwy.
• bpo-12510: Attempting to get invalid tooltip no longer closes IDLE. Othertooltipss have been corrected or improved and the number of tests has beentripled. Original patch by Roger Serwy.

Tools/Demos¶

• bpo-14695: Bring Tools/parser/unparse.py support up to date with thePython 3.3 Grammar.

Build¶

• bpo-14472: Update .gitignore. Patch by Matej Cepl.
• Upgrade Windows library versions: bzip 1.0.6, OpenSSL 1.0.1c.
• bpo-14693: Under non-Windows platforms, hashlib’s fallback modules arealways compiled, even if OpenSSL is present at build time.
• bpo-13210: Windows build now uses VS2010, ported from VS2008.

C API¶

• bpo-14705: The PyArg_Parse() family of functions now support the ‘p’format unit, which accepts a “boolean predicate” argument. It convertsany Python value into an integer–0 if it is “false”, and 1 otherwise.

Documentation¶

• bpo-14863: Update the documentation of os.fdopen() to reflect the factthat it’s only a thin wrapper around open() anymore.
• bpo-14588: The language reference now accurately documents the Python 3class definition process. Patch by Nick Coghlan.
• bpo-14943: Correct a default argument value for winreg.OpenKey andcorrectly list the argument names in the function’s explanation.

Core and Builtins¶

• bpo-14699: Fix calling the classmethod descriptor directly.
• bpo-14433: Prevent msvcrt crash in interactive prompt when stdin isclosed.
• bpo-14521: Make result of float(‘nan’) and float(‘-nan’) more consistentacross platforms.
• bpo-14646: __import__() sets __loader__ if the loader did not.
• bpo-14605: No longer have implicit entries in sys.meta_path. Ifsys.meta_path is found to be empty, raise ImportWarning.
• bpo-14605: No longer have implicit entries in sys.path_hooks. Ifsys.path_hooks is found to be empty, a warning will be raised. None is nowinserted into sys.path_importer_cache if no finder was discovered. Thisalso means imp.NullImporter is no longer implicitly used.
• bpo-13903: Implement PEP 412. Individual dictionary instances can nowshare their keys with other dictionaries. Classes take advantage of thisto share their instance dictionary keys for improved memory andperformance.
• bpo-11603: Setting __repr__ to __str__ now raises a RuntimeError whenrepr() or str() is called on such an object.
• bpo-14658: Fix binding a special method to a builtin implementation of aspecial method with a different name.
• bpo-14630: Fix a memory access bug for instances of a subclass of int withvalue 0.
• bpo-14339: Speed improvements to bin, oct and hex functions. Patch bySerhiy Storchaka.
• bpo-14385: It is now possible to use a custom type for the __builtins__namespace, instead of a dict. It can be used for sandboxing for example.Raise also a NameError instead of ImportError if __build_class__ name ifnot found in __builtins__.
• bpo-12599: Be more strict in accepting None compared to a false-likeobject for importlib.util.module_for_loader andimportlib.machinery.PathFinder.
• bpo-14612: Fix jumping around with blocks by setting f_lineno.
• bpo-14592: Attempting a relative import w/o __package__ or __name__ set inglobals raises a KeyError.
• bpo-14607: Fix keyword-only arguments which started with__.
• bpo-10854: The ImportError raised when an extension module on Windowsfails to import now uses the new path and name attributes from Issue#1559549.
• bpo-13889: Check and (if necessary) set FPU control word before callingany of the dtoa.c string <-> float conversion functions, on MSVC builds ofPython. This fixes issues when embedding Python in a Delphi app.
• __import__() now matches PEP 328 and documentation by defaulting ‘index’to 0 instead of -1 and removing support for negative values.
• bpo-2377: Make importlib the implementation of __import__().
• bpo-1559549: ImportError now has ‘name’ and ‘path’ attributes that are setusing keyword arguments to its constructor. They are currently not set byimport as they are meant for use by importlib.
• bpo-14474: Save and restore exception state in thread.start_new_thread()while writing error message if the thread leaves a unhandled exception.
• bpo-13019: Fix potential reference leaks in bytearray.extend(). Patch bySuman Saha.

Library¶

• bpo-14768: os.path.expanduser(‘~/a’) doesn’t works correctly when HOME is‘/’.
• bpo-14371: Support bzip2 in zipfile module. Patch by Serhiy Storchaka.
• bpo-13183: Fix pdb skipping frames after hitting a breakpoint and runningstep. Patch by Xavier de Gaye.
• bpo-14696: Fix parser module to understand ‘nonlocal’ declarations.
• bpo-10941: Fix imaplib.Internaldate2tuple to produce correct result nearthe DST transition. Patch by Joe Peterson.
• bpo-9154: Fix parser module to understand function annotations.
• bpo-6085: In http.server.py SimpleHTTPServer.address_string returns theclient ip address instead client hostname. Patch by Charles-FrançoisNatali.
• bpo-14309: Deprecate time.clock(), use time.perf_counter() ortime.process_time() instead.
• bpo-14428: Implement the PEP 418. Add time.get_clock_info(),time.perf_counter() and time.process_time() functions, and renametime.steady() to time.monotonic().
• bpo-14646: importlib.util.module_for_loader() now sets __loader__ and__package__ (when possible).
• bpo-14664: It is now possible to use @unittest.skip{If,Unless} on a testclass that doesn’t inherit from TestCase (i.e. a mixin).
• bpo-4892: multiprocessing Connections can now be transferred overmultiprocessing Connections. Patch by Richard Oudkerk (sbt).
• bpo-14160: TarFile.extractfile() failed to resolve symbolic links when thelinks were not located in an archive subdirectory.
• bpo-14638: pydoc now treats non-string __name__ values as if they weremissing, instead of raising an error.
• bpo-13684: Fix httplib tunnel issue of infinite loops for certain siteswhich send EOF without trailing rn.
• bpo-14605: Add importlib.abc.FileLoader, importlib.machinery.(FileFinder,SourceFileLoader, SourcelessFileLoader, ExtensionFileLoader).
• bpo-13959: imp.cache_from_source()/source_from_cache() now followos.path.join()/split() semantics for path manipulation instead of itsprior, custom semantics of caring the right-most path separator forward inpath joining.
• bpo-2193: Allow ”:” character in Cookie NAME values.
• bpo-14629: tokenizer.detect_encoding will specify the filename in theSyntaxError exception if found at readline.__self__.name.
• bpo-14629: Raise SyntaxError in tokenizer.detect_encoding if the first twolines have non-UTF-8 characters without an encoding declaration.
• bpo-14308: Fix an exception when a “dummy” thread is in the threadingmodule’s active list after a fork().
• bpo-11750: The Windows API functions scattered in the _subprocess and_multiprocessing.win32 modules now live in a single module “_winapi”.Patch by sbt.
• bpo-14087: multiprocessing: add Condition.wait_for(). Patch by sbt.
• bpo-14538: HTMLParser can now parse correctly start tags that contain abare ‘/’.
• bpo-14452: SysLogHandler no longer inserts a UTF-8 BOM into the message.
• bpo-14386: Expose the dict_proxy internal type as types.MappingProxyType.
• bpo-13959: Make imp.reload() always use a module’s __loader__ to performthe reload.
• bpo-13959: Add imp.py and rename the built-in module to _imp, allowing forre- implementing parts of the module in pure Python.
• bpo-13496: Fix potential overflow in bisect.bisect algorithm when appliedto a collection of size > sys.maxsize / 2.
• Have importlib take advantage of ImportError’s new ‘name’ and ‘path’attributes.
• bpo-14399: zipfile now recognizes that the archive has been modified evenif only the comment is changed. In addition, the TypeError that resultsfrom trying to set a non-binary value as a comment is now raised at thetime the comment is set rather than at the time the zipfile is written.
• trace.CoverageResults.is_ignored_filename() now ignores any name thatstarts with “<” and ends with “>” instead of special-casing “<string>” and“<doctest ”.
• bpo-12537: The mailbox module no longer depends on knowledge of internalimplementation details of the email package Message object.
• bpo-7978: socketserver now restarts the select() call when EINTR isreturned. This avoids crashing the server loop when a signal is received.Patch by Jerzy Kozera.
• bpo-14522: Avoid duplicating socket handles in multiprocessing.connection.Patch by sbt.
• Don’t Py_DECREF NULL variable in io.IncrementalNewlineDecoder.
• bpo-3033: Add displayof parameter to tkinter font. Patch by GuilhermePolo.
• bpo-14482: Raise a ValueError, not a NameError, when trying to create amultiprocessing Client or Listener with an AF_UNIX type address underWindows. Patch by Popa Claudiu.
• bpo-802310: Generate always unique tkinter font names if not directlypassed.
• bpo-14151: Raise a ValueError, not a NameError, when trying to create amultiprocessing Client or Listener with an AF_PIPE type address undernon-Windows platforms. Patch by Popa Claudiu.
• bpo-14493: Use gvfs-open or xdg-open in webbrowser.

Build¶

• “make touch” will now touch generated files that are checked intoMercurial, after a “hg update” which failed to bring the timestamps intothe right order.

Tests¶

• bpo-14026: In test_cmd_line_script, check that sys.argv is populatedcorrectly for the various invocation approaches (Patch by Jason Yeo)
• bpo-14032: Fix incorrect variable name in test_cmd_line_script debuggingmessage (Patch by Jason Yeo)
• bpo-14589: Update certificate chain for sha256.tbs-internet.com, fixing atest failure in test_ssl.
• bpo-14355: Regrtest now supports the standard unittest test loading, andwill use it if a test file contains notest_main method.

IDLE¶

• bpo-8515: Set __file__ when run file in IDLE. Initial patch by BruceFrederiksen.
• bpo-14496: Fix wrong name in idlelib/tabbedpages.py. Patch by PopaClaudiu.

Tools/Demos¶

• bpo-3561: The Windows installer now has an option, off by default, forplacing the Python installation into the system “Path” environmentvariable.
• bpo-13165: stringbench is now available in the Tools/stringbench folder.It used to live in its own SVN project.

C API¶

• bpo-14098: New functions PyErr_GetExcInfo and PyErr_SetExcInfo. Patch byStefan Behnel.

Core and Builtins¶

• bpo-1683368: object.__new__ and object.__init__ raise a TypeError if theyare passed arguments and their complementary method is not overridden.
• bpo-14378: Fix compiling ast.ImportFrom nodes with a “__future__” stringas the module name that was not interned.
• bpo-14331: Use significantly less stack space when importing modules byallocating path buffers on the heap instead of the stack.
• bpo-14334: Prevent in a segfault in type.__getattribute__ when it was notpassed strings.
• bpo-1469629: Allow cycles through an object’s __dict__ slot to becollected. (For example ifx.__dict__isx).
• bpo-14205: dict lookup raises a RuntimeError if the dict is modifiedduring a lookup.
• bpo-14220: When a generator is delegating to another iterator with theyield from syntax, it needs to have itsgi_running flag set to True.
• bpo-14435: Remove dedicated block allocator from floatobject.c and rely onthe PyObject_Malloc() api like all other objects.
• bpo-14471: Fix a possible buffer overrun in the winreg module.
• bpo-14288: Allow the serialization of builtin iterators

Library¶

• bpo-14300: Under Windows, sockets created using socket.dup() now allowoverlapped I/O. Patch by sbt.
• bpo-13872: socket.detach() now marks the socket closed (as mirrored in thesocket repr()). Patch by Matt Joiner.
• bpo-14406: Fix a race condition when usingconcurrent.futures.wait(return_when=ALL_COMPLETED). Patch by Matt Joiner.
• bpo-5136: deprecate old, unused functions from tkinter.
• bpo-14416: syslog now defines the LOG_ODELAY and LOG_AUTHPRIV constants ifthey are defined in <syslog.h>.
• bpo-14295: Add unittest.mock
• bpo-7652: Add –with-system-libmpdec option to configure for linking the_decimal module against an installed libmpdec.
• bpo-14380: MIMEText now defaults to utf-8 when passed non-ASCII unicodewith no charset specified.
• bpo-10340: asyncore - properly handle EINVAL in dispatcher constructor onOSX; avoid to call handle_connect in case of a disconnected socket whichwas not meant to connect.
• bpo-14204: The ssl module now has support for the Next ProtocolNegotiation extension, if available in the underlying OpenSSL library.Patch by Colin Marc.
• bpo-3035: Unused functions from tkinter are marked as pending deprecated.
• bpo-12757: Fix the skipping of doctests when python is run with -OO sothat it works in unittest’s verbose mode as well as non-verbose mode.
• bpo-7652: Integrate the decimal floating point libmpdec library to speedup the decimal module. Performance gains of the new C implementation arebetween 10x and 100x, depending on the application.
• bpo-14269: SMTPD now conforms to the RFC and requires a HELO commandbefore MAIL, RCPT, or DATA.
• bpo-13694: asynchronous connect in asyncore.dispatcher does not set addrattribute.
• bpo-14344: fixed the repr of email.policy objects.
• bpo-11686: Added missing entries to email package __all__ lists (mostlythe new Bytes classes).
• bpo-14335: multiprocessing’s custom Pickler subclass now inherits from theC-accelerated implementation. Patch by sbt.
• bpo-10484: Fix the CGIHTTPServer’s PATH_INFO handling problem.
• bpo-11199: Fix the with urllib which hangs on particular ftp urls.
• Improve the memory utilization and speed of functools.lru_cache.
• bpo-14222: Use the new time.steady() function instead of time.time() fortimeout in queue and threading modules to not be affected of system timeupdate.
• bpo-13248: Remove lib2to3.pytree.Base.get_prefix/set_prefix.
• bpo-14234: CVE-2012-0876: Randomize hashes of xml attributes in the hashtable internal to the pyexpat module’s copy of the expat library to avoida denial of service due to hash collisions. Patch by David Malcolm withsome modifications by the expat project.
• bpo-12818: format address no longer needlessly escapes ()s in names whenthe name ends up being quoted.
• bpo-14062: BytesGenerator now correctly folds Header objects, includingusing linesep when folding.
• bpo-13839: When invoked on the command-line, the pstats module now acceptsseveral filenames of profile stat files and merges them all. Patch by MattJoiner.
• bpo-14291: Email now defaults to utf-8 for non-ASCII unicode headersinstead of raising an error. This fixes a regression relative to 2.7.
• bpo-989712: Support using Tk without a mainloop.
• bpo-3835: Refuse to use unthreaded Tcl in threaded Python.
• bpo-2843: Add new Tk API to Tkinter.
• bpo-14184: Increase the default stack size for secondary threads on Mac OSX to avoid interpreter crashes when using threads on 10.7.
• bpo-14180: datetime.date.fromtimestamp(),datetime.datetime.fromtimestamp() and datetime.datetime.utcfromtimestamp()now raise an OSError instead of ValueError if localtime() or gmtime()failed.
• bpo-14180: time.ctime(), gmtime(), time.localtime(),datetime.date.fromtimestamp(), datetime.datetime.fromtimestamp() anddatetime.datetime.utcfromtimestamp() now raises an OverflowError, insteadof a ValueError, if the timestamp does not fit in time_t.
• bpo-14180: datetime.datetime.fromtimestamp() anddatetime.datetime.utcfromtimestamp() now round microseconds towards zeroinstead of rounding to nearest with ties going away from zero.
• bpo-10543: Fix unittest test discovery with Jython bytecode files.
• bpo-1178863: Separate initialisation from setting when initializingTkinter.Variables; harmonize exceptions to ValueError; only deletevariables that have not been deleted; assert that variable names arestrings.
• bpo-14104: Implement time.monotonic() on Mac OS X, patch written byNicholas Riley.
• bpo-13394: the aifc module now uses warnings.warn() to signal warnings.
• bpo-14252: Fix subprocess.Popen.terminate() to not raise an error underWindows when the child process has already exited.
• bpo-14223: curses.addch() is no more limited to the range 0-255 when thePython curses is not linked to libncursesw. It was a regression introducedin Python 3.3a1.
• bpo-14168: Check for presence of Element._attrs in minidom beforeaccessing it.
• bpo-12328: Fix multiprocessing’s use of overlapped I/O on Windows. Also,add a multiprocessing.connection.wait(rlist, timeout=None) function forpolling multiple objects at once. Patch by sbt.
• bpo-14007: Accept incomplete TreeBuilder objects (missing start, end, dataor close method) for the Python implementation as well. Drop the no-opTreeBuilder().xml() method from the C implementation.
• bpo-14210: pdb now has tab-completion not only for command names, but alsofor their arguments, wherever possible.
• bpo-14310: Sockets can now be with other processes on Windows using theapi socket.socket.share() and socket.fromshare().
• bpo-10576: The gc module now has a ‘callbacks’ member that will get calledwhen garbage collection takes place.

Build¶

• bpo-14557: Fix extensions build on HP-UX. Patch by Adi Roiban.
• bpo-14387: Do not include accu.h from Python.h.
• bpo-14359: Only use O_CLOEXEC in _posixmodule.c if it is defined. Based onpatch from Hervé Coatanhay.
• bpo-14321: Do not run pgen during the build if files are up to date.

Documentation¶

• bpo-14034: added the argparse tutorial.
• bpo-14324: Fix configure tests for cross builds.
• bpo-14327: Call AC_CANONICAL_HOST in configure.ac and check inconfig.{guess,sub}. Don’t use uname calls for cross builds.

Library¶

• bpo-9041: An issue in ctypes.c_longdouble, ctypes.c_double, andctypes.c_float that caused an incorrect exception to be returned in thecase of overflow has been fixed.
• bpo-14212: The re module didn’t retain a reference to buffers it wasscanning, resulting in segfaults.
• bpo-14259: The finditer() method of re objects did not take any keywordarguments, contrary to the documentation.
• bpo-10142: Support for SEEK_HOLE/SEEK_DATA (for example, under ZFS).

Tests¶

• bpo-14442: Add missing errno import in test_smtplib.
• bpo-8315: (partial fix) python -m unittest test.test_email now works.

Core and Builtins¶

• bpo-14172: Fix reference leak when marshalling a buffer-like object (otherthan a bytes object).

• bpo-13521: dict.setdefault() now does only one lookup for the given key,making it “atomic” for many purposes. Patch by Filip Gruszczyński.

• PEP 409,Issue #6210: “raise X from None” is now supported as a means ofsuppressing the display of the chained exception context. The chainedcontext still remains available as the __context__ attribute.

• bpo-10181: New memoryview implementation fixes multiple ownership andlifetime issues of dynamically allocated Py_buffer members (#9990) as wellas crashes (#8305, #7433). Many new features have been added (Seewhatsnew/3.3), and the documentation has been updated extensively. Thendarray test object from _testbuffer.c implements all aspects of PEP-3118,so further development towards the complete implementation of the PEP canproceed in a test-driven manner.

  Thanks to Nick Coghlan, Antoine Pitrou and Pauli Virtanen for review andmany ideas.

• bpo-12834: Fix incorrect results of memoryview.tobytes() fornon-contiguous arrays.

• bpo-5231: Introduce memoryview.cast() method that allows changing formatand shape without making a copy of the underlying memory.

• bpo-14084: Fix a file descriptor leak when importing a module with a badencoding.

• Upgrade Unicode data to Unicode 6.1.

• bpo-14040: Remove rarely used file name suffixes for C extensions (underPOSIX mainly).

• bpo-14051: Allow arbitrary attributes to be set of classmethod andstaticmethod.

• bpo-13703: oCERT-2011-003: Randomize hashes of str and bytes to protectagainst denial of service attacks due to hash collisions within the dictand set types. Patch by David Malcolm, based on work by Victor Stinner.

• bpo-13020: Fix a reference leak when allocating a structsequence objectfails. Patch by Suman Saha.

• bpo-13908: Ready types returned from PyType_FromSpec.

• bpo-11235: Fix OverflowError when trying to import a source file whosemodification time doesn’t fit in a 32-bit timestamp.

• bpo-12705: A SyntaxError exception is now raised when attempting tocompile multiple statements as a single interactive statement.

• Fix the builtin module initialization code to store the init function forfuture reinitialization.

• bpo-8052: The posix subprocess module would take a long time closing allpossible file descriptors in the child process rather than just open filedescriptors. It now closes only the open fds if possible for the defaultclose_fds=True behavior.

• bpo-13629: Renumber the tokens in token.h so that they match the indexesinto _PyParser_TokenNames.

• bpo-13752: Add a casefold() method to str.

• bpo-13761: Add a “flush” keyword argument to the print() function, used toensure flushing the output stream.

• bpo-13645: pyc files now contain the size of the corresponding sourcecode, to avoid timestamp collisions (especially on filesystems with a lowtimestamp resolution) when checking for freshness of the bytecode.

• PEP 380,Issue #11682: Add “yield from <x>” to support easy delegation tosubgenerators (initial patch by Greg Ewing, integration into 3.3 by RenaudBlanch, Ryan Kelly, Zbigniew Jędrzejewski-Szmek and Nick Coghlan)

• bpo-13748: Raw bytes literals can now be written with therb prefix aswell asbr.

• bpo-12736: Use full unicode case mappings for upper, lower, and titlecase.

• bpo-12760: Add a create mode to open(). Patch by David Townshend.

• bpo-13738: Simplify implementation of bytes.lower() and bytes.upper().

• bpo-13577: Built-in methods and functions now have a __qualname__. Patchby sbt.

• bpo-6695: Full garbage collection runs now clear the freelist of setobjects. Initial patch by Matthias Troffaes.

• Fix OSError.__init__ and OSError.__new__ so that each of them can beoverriden and take additional arguments (followup toissue #12555).

• Fix the fix forissue #12149: it was incorrect, although it had the sideeffect of appearing to resolve the issue. Thanks to Mark Shannon fornoticing.

• bpo-13505: Pickle bytes objects in a way that is compatible with Python 2when using protocols <= 2.

• bpo-11147: Fix an unused argument in _Py_ANNOTATE_MEMORY_ORDER. (Fixgiven by Campbell Barton).

• bpo-13503: Use a more efficient reduction format for bytearrays withpickle protocol >= 3. The old reduction format is kept with olderprotocols in order to allow unpickling under Python 2. Patch by Irmen deJong.

• bpo-7111: Python can now be run without a stdin, stdout or stderr stream.It was already the case with Python 2. However, the corresponding sysmodule entries are now set to None (instead of an unusable file object).

• bpo-11849: Ensure that free()d memory arenas are really released on POSIXsystems supporting anonymous memory mappings. Patch by Charles-FrançoisNatali.

• PEP 3155 /issue #13448: Qualified name for classes and functions.

• bpo-13436: Fix a bogus error message when an AST object was passed aninvalid integer value.

• bpo-13411: memoryview objects are now hashable when the underlying objectis hashable.

• bpo-13338: Handle all enumerations in _Py_ANNOTATE_MEMORY_ORDER to allowcompiling extension modules with -Wswitch-enum on gcc. Initial patch byFloris Bruynooghe.

• bpo-10227: Add an allocation cache for a single slice object. Patch byStefan Behnel.

• bpo-13393: BufferedReader.read1() now asks the full requested size to theraw stream instead of limiting itself to the buffer size.

• bpo-13392: Writing a pyc file should now be atomic under Windows as well.

• bpo-13333: The UTF-7 decoder now accepts lone surrogates (the encoderalready accepts them).

• bpo-13389: Full garbage collection passes now clear the freelists for listand dict objects. They already cleared other freelists in theinterpreter.

• bpo-13327: Remove the need for an explicit None as the second argument toos.utime, os.lutimes, os.futimes, os.futimens, os.futimesat, in order toupdate to the current time. Also added keyword argument handling toos.utimensat in order to remove the need for explicit None.

• bpo-13350: Simplify some C code by replacing most usages ofPyUnicode_Format by PyUnicode_FromFormat.

• bpo-13342: input() used to ignore sys.stdin’s and sys.stdout’s unicodeerror handler in interactive mode (when calling into PyOS_Readline()).

• bpo-9896: Add start, stop, and step attributes to range objects.

• bpo-13343: Fix a SystemError when a lambda expression uses a globalvariable in the default value of a keyword-only argument:lambda*,arg=GLOBAL_NAME:None

• bpo-12797: Added custom opener parameter to builtin open() andFileIO.open().

• bpo-10519: Avoid unnecessary recursive function calls in setobject.c.

• bpo-10363: Deallocate global locks in Py_Finalize().

• bpo-13018: Fix reference leaks in error paths in dictobject.c. Patch bySuman Saha.

• bpo-13201: Define ‘==’ and ‘!=’ to compare range objects based on thesequence of values they define (instead of comparing based on objectidentity).

• bpo-1294232: In a few cases involving metaclass inheritance, theinterpreter would sometimes invoke the wrong metaclass when building a newclass object. These cases now behave correctly. Patch by Daniel Urban.

• bpo-12753: Add support for Unicode name aliases and named sequences. Bothunicodedata.lookup() and ‘N{...}’ now resolve aliases, andunicodedata.lookup() resolves named sequences too.

• bpo-12170: The count(), find(), rfind(), index() and rindex() methods ofbytes and bytearray objects now accept an integer between 0 and 255 astheir first argument. Patch by Petri Lehtinen.

• bpo-12604: VTRACE macro expanded to no-op in _sre.c to avoid compilerwarnings. Patch by Josh Triplett and Petri Lehtinen.

• bpo-12281: Rewrite the MBCS codec to handle correctly replace and ignoreerror handlers on all Windows versions. The MBCS codec is now supportingall error handlers, instead of only replace to encode and ignore todecode.

• bpo-13188: When called without an explicit traceback argument,generator.throw() now gets the traceback from the passed exception’s__traceback__ attribute. Patch by Petri Lehtinen.

• bpo-13146: Writing a pyc file is now atomic under POSIX.

• bpo-7833: Extension modules built using distutils on Windows will nolonger include a “manifest” to prevent them failing at import time in someembedded situations.

• PEP 3151 /issue #12555: reworking the OS and IO exception hierarchy.

• Add internal API for static strings (_Py_identifier et al.).

• bpo-13063: the Windows error ERROR_NO_DATA (numbered 232 and described as“The pipe is being closed”) is now mapped to POSIX errno EPIPE (previouslyEINVAL).

• bpo-12911: Fix memory consumption when calculating the repr() of hugetuples or lists.

• PEP 393: flexible string representation. Thanks to Torsten Becker for theinitial implementation, and Victor Stinner for various bug fixes.

• bpo-14081: The ‘sep’ and ‘maxsplit’ parameter to str.split, bytes.split,and bytearray.split may now be passed as keyword arguments.

• bpo-13012: The ‘keepends’ parameter to str.splitlines may now be passed asa keyword argument: “my_string.splitlines(keepends=True)”. The samechange also applies to bytes.splitlines and bytearray.splitlines.

• bpo-7732: Don’t open a directory as a file anymore while importing amodule. Ignore the direcotry if its name matchs the module name (e.g.“__init__.py”) and raise a ImportError instead.

• bpo-13021: Missing decref on an error path. Thanks to Suman Saha forfinding the bug and providing a patch.

• bpo-12973: Fix overflow checks that relied on undefined behaviour inlist_repeat (listobject.c) and islice_next (itertoolsmodule.c). Thesebugs caused test failures with recent versions of Clang.

• bpo-12904: os.utime, os.futimes, os.lutimes, and os.futimesat now writeatime and mtime with nanosecond precision on modern POSIX platforms.

• bpo-12802: the Windows error ERROR_DIRECTORY (numbered 267) is now mappedto POSIX errno ENOTDIR (previously EINVAL).

• bpo-9200: The str.is* methods now work with strings that contain non-BMPcharacters even in narrow Unicode builds.

• bpo-12791: Break reference cycles early when a generator exits with anexception.

• bpo-12773: Make __doc__ mutable on user-defined classes.

• bpo-12766: Raise a ValueError when creating a class with a class variablethat conflicts with a name in __slots__.

• bpo-12266: Fix str.capitalize() to correctly uppercase/lowercasetitlecased and cased non-letter characters.

• bpo-12732: In narrow unicode builds, allow Unicode identifiers which falloutside the BMP.

• bpo-12575: Validate user-generated AST before it is compiled.

• Make type(None), type(Ellipsis), and type(NotImplemented) callable. Theyreturn the respective singleton instances.

• Forbid summing bytes with sum().

• Verify the types of AST strings and identifiers provided by the userbefore compiling them.

• bpo-12647: The None object now has a __bool__() method that returns False.Formerly, bool(None) returned False only because of special case logic inPyObject_IsTrue().

• bpo-12579: str.format_map() now raises a ValueError if used on a formatstring that contains positional fields. Initial patch by Julian Berman.

• bpo-10271: Allow warnings.showwarning() be any callable.

• bpo-11627: Fix segfault when __new__ on a exception returns anon-exception class.

• bpo-12149: Update the method cache after a type’s dictionary gets clearedby the garbage collector. This fixes a segfault when an instance and itstype get caught in a reference cycle, and the instance’s deallocator callsone of the methods on the type (e.g. when subclassing IOBase). Diagnosisand patch by Davide Rizzo.

• bpo-9611: FileIO.read() clamps the length to INT_MAX on Windows. (Seealso: bpo-9015)

• bpo-9642: Uniformize the tests on the availability of the mbcs codec, adda new HAVE_MBCS define.

• bpo-9642: Fix filesystem encoding initialization: use the ANSI code pageon Windows if the mbcs codec is not available, and fail with a fatal errorif we cannot get the locale encoding (if nl_langinfo(CODESET) is notavailable) instead of using UTF-8.

• When a generator yields, do not retain the caller’s exception state on thegenerator.

• bpo-12475: Prevent generators from leaking their exception state into thecaller’s frame as they return for the last time.

• bpo-12291: You can now load multiple marshalled objects from a stream,with other data interleaved between marshalled objects.

• bpo-12356: When required positional or keyword-only arguments are notgiven, produce a informative error message which includes the name(s) ofthe missing arguments.

• bpo-12370: Fix super with no arguments when __class__ is overriden in theclass body.

• bpo-12084: os.stat on Windows now works properly with relative symboliclinks when called from any directory.

• Loosen type restrictions on the __dir__ method. __dir__ can now return anysequence, which will be converted to a list and sorted by dir().

• bpo-12265: Make error messages produced by passing an invalid set ofarguments to a function more informative.

• bpo-12225: Still allow Python to build if Python is not in its hg repo ormercurial is not installed.

• bpo-1195: my_fgets() now always clears errors before calling fgets(). Fixthe following case: sys.stdin.read() stopped with CTRL+d (end of file),raw_input() interrupted by CTRL+c.

• bpo-12216: Allow unexpected EOF errors to happen on any line of the file.

• bpo-12199: The TryExcept and TryFinally and AST nodes have been unifiedinto a Try node.

• bpo-9670: Increase the default stack size for secondary threads on Mac OSX and FreeBSD to reduce the chances of a crash instead of a “maximumrecursion depth” RuntimeError exception. (patch by Ronald Oussoren)

• bpo-12106: The use of the multiple-with shorthand syntax is now reflectedin the AST.

• bpo-12190: Try to use the same filename object when compilingunmarshalling a code objects in the same file.

• bpo-12166: Move implementations of dir() specialized for various typesinto the __dir__() methods of those types.

• bpo-5715: In socketserver, close the server socket in the child process.

• Correct lookup of __dir__ on objects. Among other things, this causeserrors besides AttributeError found on lookup to be propagated.

• bpo-12060: Use sig_atomic_t type and volatile keyword in the signalmodule. Patch written by Charles-François Natali.

• bpo-1746656: Added the if_nameindex, if_indextoname, if_nametoindexmethods to the socket module.

• bpo-12044: Fixed subprocess.Popen when used as a context manager to waitfor the process to end when exiting the context to avoid unintentionallyleaving zombie processes around.

• bpo-1195: Fix input() if it is interrupted by CTRL+d and then CTRL+c,clear the end- of-file indicator after CTRL+d.

• bpo-1856: Avoid crashes and lockups when daemon threads run while theinterpreter is shutting down; instead, these threads are now killed whenthey try to take the GIL.

• bpo-9756: When calling a method descriptor or a slot wrapper descriptor,the check of the object type doesn’t read the __class__ attribute anymore.Fix a crash if a class override its __class__ attribute (e.g. a proxy ofthe str type). Patch written by Andreas Stührk.

• bpo-10517: After fork(), reinitialize the TLS used by the PyGILState_*APIs, to avoid a crash with the pthread implementation in RHEL 5. Patchby Charles-François Natali.

• bpo-10914: Initialize correctly the filesystem codec when creating a newsubinterpreter to fix a bootstrap issue with codecs implemented in Python,as the ISO-8859-15 codec.

• bpo-11918: OS/2 and VMS are no more supported because of the lack ofmaintainer.

• bpo-6780: fix starts/endswith error message to mention that tuples areaccepted too.

• bpo-5057: fix a bug in the peepholer that led to non-portable pyc filesbetween narrow and wide builds while optimizing BINARY_SUBSCR on non-BMPchars (e.g. “U00012345”[0]).

• bpo-11845: Fix typo in rangeobject.c that caused a crash incompute_slice_indices. Patch by Daniel Urban.

• bpo-5673: Added atimeout keyword argument to subprocess.Popen.wait,subprocess.Popen.communicated, subprocess.call, subprocess.check_call, andsubprocess.check_output. If the blocking operation takes more thantimeout seconds, thesubprocess.TimeoutExpired exception is raised.

• bpo-11650: PyOS_StdioReadline() retries fgets() if it was interrupted(EINTR), for example if the program is stopped with CTRL+z on Mac OS X.Patch written by Charles-Francois Natali.

• bpo-9319: Include the filename in “Non-UTF8 code ...” syntax error.

• bpo-10785: Store the filename as Unicode in the Python parser.

• bpo-11619: _PyImport_LoadDynamicModule() doesn’t encode the path to byteson Windows.

• bpo-10998: Remove mentions of -Q, sys.flags.division_warning andPy_DivisionWarningFlag left over from Python 2.

• bpo-11244: Remove an unnecessary peepholer check that was preventingnegative zeros from being constant-folded properly.

• bpo-11395: io.FileIO().write() clamps the data length to 32,767 bytes onWindows if the file is a TTY to workaround a Windows bug. The Windowsconsole returns an error (12: not enough space error) on writing intostdout if stdout mode is binary and the length is greater than 66,000bytes (or less, depending on heap usage).

• bpo-11320: fix bogus memory management in Modules/getpath.c, leading to apossible crash when calling Py_SetPath().

• bpo-11432: A bug was introduced in subprocess.Popen on posix systems with3.2.0 where the stdout or stderr file descriptor being the same as thestdin file descriptor would raise an exception. webbrowser.open wouldfail. fixed.

• bpo-9856: Change object.__format__ with a non-empty format string to be aDeprecationWarning. In 3.2 it was a PendingDeprecationWarning. In 3.4 itwill be a TypeError.

• bpo-11244: The peephole optimizer is now able to constant-fold arbitrarilycomplex expressions. This also fixes a 3.2 regression where operationsinvolving negative numbers were not constant-folded.

• bpo-11450: Don’t truncate hg version info in Py_GetBuildInfo() when thereare many tags (e.g. when using mq). Patch by Nadeem Vawda.

• bpo-11335: Fixed a memory leak in list.sort when the key function throwsan exception.

• bpo-8923: When a string is encoded to UTF-8 in strict mode, the result iscached into the object. Examples: str.encode(), str.encode(‘utf-8’),PyUnicode_AsUTF8String() and PyUnicode_AsEncodedString(unicode, “utf-8”,NULL).

• bpo-10829: Refactor PyUnicode_FromFormat(), use the same function to parsethe format string in the 3 steps, fix crashs on invalid format strings.

• bpo-13007: whichdb should recognize gdbm 1.9 magic numbers.

• bpo-11286: Raise a ValueError from calling PyMemoryView_FromBuffer with abuffer struct having a NULL data pointer.

• bpo-11272: On Windows, input() strips ‘r’ (and not only ‘n’), andsys.stdin uses universal newline (replace ‘rn’ by ‘n’).

• bpo-11828: startswith and endswith now accept None as slice index. Patchby Torsten Becker.

• bpo-11168: Remove filename debug variable from PyEval_EvalFrameEx(). Itencoded the Unicode filename to UTF-8, but the encoding fails onundecodable filename (on surrogate characters) which raises an unexpectedUnicodeEncodeError on recursion limit.

• bpo-11187: Remove bootstrap code (use ASCII) ofPyUnicode_AsEncodedString(), it was replaced by a better fallback (use thelocale encoding) in PyUnicode_EncodeFSDefault().

• Check for NULL result in PyType_FromSpec.

• bpo-10516: New copy() and clear() methods for lists and bytearrays.

• bpo-11386: bytearray.pop() now throws IndexError when the bytearray isempty, instead of OverflowError.

• bpo-12380: The rjust, ljust and center methods of bytes and bytearray nowaccept a bytearray argument.

Library¶

• bpo-14195: An issue that caused weakref.WeakSet instances to incorrectlyreturn True for a WeakSet instance ‘a’ in both ‘a < a’ and ‘a > a’ hasbeen fixed.
• bpo-14166: Pickler objects now have an optionaldispatch_tableattribute which allows to set custom per-pickler reduction functions.Patch by sbt.
• bpo-14177: marshal.loads() now raises TypeError when given an unicodestring. Patch by Guilherme Gonçalves.
• bpo-13550: Remove the debug machinery from the threading module: removeverbose arguments from all threading classes and functions.
• bpo-14159: Fix the len() of weak containers (WeakSet, WeakKeyDictionary,WeakValueDictionary) to return a better approximation when some objectsare dead or dying. Moreover, the implementation is now O(1) rather thanO(n).
• bpo-11841: Fix comparison bug with ‘rc’ versions in packaging.version.Patch by Filip Gruszczyński.
• bpo-6884: Fix long-standing bugs with MANIFEST.in parsing in distutils onWindows. Also fixed in packaging.
• bpo-8033: sqlite3: Fix 64-bit integer handling in user functions on 32-bitarchitectures. Initial patch by Philippe Devalkeneer.
• HTMLParser is now able to handle slashes in the start tag.
• bpo-13641: Decoding functions in the base64 module now accept ASCII-onlyunicode strings. Patch by Catalin Iacob.
• bpo-14043: Speed up importlib’s _FileFinder by at least 8x, and add a newimportlib.invalidate_caches() function.
• bpo-14001: CVE-2012-0845: xmlrpc: Fix an endless loop inSimpleXMLRPCServer upon malformed POST request.
• bpo-13961: Move importlib over to using os.replace() for atomic renaming.
• Do away with ambiguous level values (as suggested by PEP 328) inimportlib.__import__() by raising ValueError when level < 0.
• bpo-2489: pty.spawn could consume 100% cpu when it encountered an EOF.
• bpo-13014: Fix a possible reference leak in SSLSocket.getpeercert().
• bpo-13777: Add PF_SYSTEM sockets on OS X. Patch by Michael Goderbauer.
• bpo-13015: Fix a possible reference leak in defaultdict.__repr__. Patch bySuman Saha.
• bpo-1326113: distutils’ and packaging’s build_ext commands option nowcorrectly parses multiple values (separated by whitespace or commas) givento their –libraries option.
• bpo-10287: nntplib now queries the server’s CAPABILITIES first beforesending MODE READER, and only sends it if not already in READER mode.Patch by Hynek Schlawack.
• bpo-13993: HTMLParser is now able to handle broken end tags whenstrict=False.
• bpo-13930: lib2to3 now supports writing converted output files to anotherdirectory tree as well as copying unchanged files and altering the filesuffix.
• bpo-9750: Fix sqlite3.Connection.iterdump on tables and fields with a namethat is a keyword or contains quotes. Patch by Marko Kohtala.
• bpo-10287: nntplib now queries the server’s CAPABILITIES again afterauthenticating (since the result may change, according to RFC 4643). Patchby Hynek Schlawack.
• bpo-13590: On OS X 10.7 and 10.6 with Xcode 4.2, building Distutils-basedpackages with C extension modules may fail because Apple has removedgcc-4.2, the version used to build python.org 64-bit/32-bit Pythons. Ifthe user does not explicitly override the default C compiler by settingthe CC environment variable, Distutils will now attempt to compileextension modules with clang if gcc-4.2 is required but not found. Also asa convenience, if the user does explicitly set CC, substitute its value asthe default compiler in the Distutils LDSHARED configuration variable forOS X. (Note, the python.org 32-bit-only Pythons use gcc-4.0 and the 10.4uSDK, neither of which are available in Xcode 4. This change does notattempt to override settings to support their use with Xcode 4.)
• bpo-13960: HTMLParser is now able to handle broken comments whenstrict=False.
• When ‘’ is a path (e.g. in sys.path), make sure __file__ uses the currentworking directory instead of ‘’ in importlib.
• bpo-13609: Add two functions to query the terminal size:os.get_terminal_size (low level) and shutil.get_terminal_size (highlevel). Patch by Zbigniew Jędrzejewski-Szmek.
• bpo-13845: On Windows, time.time() now uses GetSystemTimeAsFileTime()instead of ftime() to have a resolution of 100 ns instead of 1 ms (theclock accuracy is between 0.5 ms and 15 ms).
• bpo-13846: Add time.monotonic(), monotonic clock.
• bpo-8184: multiprocessing: On Windows, don’t set SO_REUSEADDR onConnection sockets, and set FILE_FLAG_FIRST_PIPE_INSTANCE on named pipes,to make sure two listeners can’t bind to the same socket/pipe (or anyexisting socket/pipe).
• bpo-10811: Fix recursive usage of cursors. Instead of crashing, raise aProgrammingError now.
• bpo-13734: Add os.fwalk(), a directory walking function yielding filedescriptors.
• bpo-2945: Make the distutils upload command aware of bdist_rpm products.
• bpo-13712: pysetup create should not convert package_data to extra_files.
• bpo-11805: package_data in setup.cfg should allow more than one value.
• bpo-13676: Handle strings with embedded zeros correctly in sqlite3.
• bpo-8828: Add new function os.replace(), for cross-platform renaming withoverwriting.
• bpo-13848: open() and the FileIO constructor now check for NUL charactersin the file name. Patch by Hynek Schlawack.
• bpo-13806: The size check in audioop decompression functions was toostrict and could reject valid compressed data. Patch by Oleg Plakhotnyuk.
• bpo-13812: When a multiprocessing Process child raises an exception, flushstderr after printing the exception traceback.
• bpo-13885: CVE-2011-3389: the _ssl module would always disable the CBC IVattack countermeasure.
• bpo-13847: time.localtime() and time.gmtime() now raise an OSError insteadof ValueError on failure. time.ctime() and time.asctime() now raises anOSError if localtime() failed. time.clock() now raises a RuntimeError ifthe processor time used is not available or its value cannot berepresented
• bpo-13772: In os.symlink() under Windows, do not try to guess the linktarget’s type (file or directory). The detection was buggy and made thecall non-atomic (therefore prone to race conditions).
• bpo-6631: Disallow relative file paths in urllib urlopen methods.
• bpo-13722: Avoid silencing ImportErrors when initializing the codecsregistry.
• bpo-13781: Fix GzipFile bug that caused an exception to be raised whenopening for writing using a fileobj returned by os.fdopen().
• bpo-13803: Under Solaris, distutils doesn’t include bitness in thedirectory name.
• bpo-10278: Add time.wallclock() function, monotonic clock.
• bpo-13809: Fix regression where bz2 module wouldn’t work when threads aredisabled. Original patch by Amaury Forgeot d’Arc.
• bpo-13589: Fix some serialization primitives in the aifc module. Patch byOleg Plakhotnyuk.
• bpo-13642: Unquote before b64encoding user:password during BasicAuthentication. Patch contributed by Joonas Kuorilehto.
• bpo-12364: Fix a hang in concurrent.futures.ProcessPoolExecutor. The hangwould occur when retrieving the result of a scheduled future after theexecutor had been shut down.
• bpo-13502: threading: Fix a race condition in Event.wait() that made itreturn False when the event was set and cleared right after.
• bpo-9993: When the source and destination are on different filesystems,and the source is a symlink, shutil.move() now recreates a symlink on thedestination instead of copying the file contents. Patch by JonathanNiehof and Hynek Schlawack.
• bpo-12926: Fix a bug in tarfile’s link extraction.
• bpo-13696: Fix the 302 Relative URL Redirection problem.
• bpo-13636: Weak ciphers are now disabled by default in the ssl module(except when SSLv2 is explicitly asked for).
• bpo-12715: Add an optional symlinks argument to shutil functions(copyfile, copymode, copystat, copy, copy2). When that parameter is true,symlinks aren’t dereferenced and the operation instead acts on the symlinkitself (or creates one, if relevant). Patch by Hynek Schlawack.
• Add a flags parameter to select.epoll.
• bpo-13626: Add support for SSL Diffie-Hellman key exchange, through theSSLContext.load_dh_params() method and the ssl.OP_SINGLE_DH_USE option.
• bpo-11006: Don’t issue low level warning in subprocess when pipe2() fails.
• bpo-13620: Support for Chrome browser in webbrowser. Patch contributed byArnaud Calmettes.
• bpo-11829: Fix code execution holes in inspect.getattr_static formetaclasses with metaclasses. Patch by Andreas Stührk.
• bpo-12708: Add starmap() and starmap_async() methods (similar toitertools.starmap()) to multiprocessing.Pool. Patch by Hynek Schlawack.
• bpo-1785: Fix inspect and pydoc with misbehaving descriptors.
• bpo-13637: “a2b” functions in the binascii module now accept ASCII-onlyunicode strings.
• bpo-13634: Add support for querying and disabling SSL compression.
• bpo-13627: Add support for SSL Elliptic Curve-based Diffie-Hellman keyexchange, through the SSLContext.set_ecdh_curve() method and thessl.OP_SINGLE_ECDH_USE option.
• bpo-13635: Add ssl.OP_CIPHER_SERVER_PREFERENCE, so that SSL servers choosethe cipher based on their own preferences, rather than on the client’s.
• bpo-11813: Fix inspect.getattr_static for modules. Patch by AndreasStührk.
• bpo-7502: Fix equality comparison for DocTestCase instances. Patch byCédric Krier.
• bpo-11870: threading: Properly reinitialize threads internal locks andcondition variables to avoid deadlocks in child processes.
• bpo-8035: urllib: Fix a bug where the client could remain stuck after aredirection or an error.
• bpo-13560: os.strerror() now uses the current locale encoding instead ofUTF-8.
• bpo-8373: The filesystem path of AF_UNIX sockets now uses the filesystemencoding and the surrogateescape error handler, rather than UTF-8. Patchby David Watson.
• bpo-10350: Read and save errno before calling a function which mightoverwrite it. Original patch by Hallvard B Furuseth.
• bpo-11610: Introduce a more general way to declare abstract properties.
• bpo-13591: A bug in importlib has been fixed that caused import_module toload a module twice.
• bpo-13449: sched.scheduler.run() method has a new “blocking” parameterwhich when set to False makes run() execute the scheduled events due toexpire soonest (if any) and then return. Patch by Giampaolo Rodolà.
• bpo-8684: sched.scheduler class can be safely used in multi-threadedenvironments. Patch by Josiah Carlson and Giampaolo Rodolà.
• Alias resource.error to OSError ala PEP 3151.
• bpo-5689: Add support for lzma compression to the tarfile module.
• bpo-13248: Turn 3.2’s PendingDeprecationWarning into 3.3’sDeprecationWarning. It covers ‘cgi.escape’, ‘importlib.abc.PyLoader’,‘importlib.abc.PyPycLoader’, ‘nntplib.NNTP.xgtitle’, ‘nntplib.NNTP.xpath’,and private attributes of ‘smtpd.SMTPChannel’.
• bpo-5905: time.strftime() is now using the current locale encoding,instead of UTF-8, if the wcsftime() function is not available. (See also:bpo-13560)
• bpo-13464: Add a readinto() method to http.client.HTTPResponse. Patch byJon Kuhn.
• tarfile.py: Correctly detect bzip2 compressed streams with blocksizesother than 900k.
• bpo-13439: Fix many errors in turtle docstrings.
• bpo-6715: Add a module ‘lzma’ for compression using the LZMA algorithm.Thanks to Per Øyvind Karlsen for the initial implementation.
• bpo-13487: Make inspect.getmodule robust against changes done tosys.modules while it is iterating over it.
• bpo-12618: Fix a bug that prevented py_compile from creating byte compiledfiles in the current directory. Initial patch by Sjoerd de Vries.
• bpo-13444: When stdout has been closed explicitly, we should not attemptto flush it at shutdown and print an error.
• bpo-12567: The curses module uses Unicode functions for Unicode argumentswhen it is linked to the ncurses library. It encodes also Unicode stringsto the locale encoding instead of UTF-8.
• bpo-12856: Ensure child processes do not inherit the parent’s random seedfor filename generation in the tempfile module. Patch by Brian Harring.
• bpo-9957: SpooledTemporaryFile.truncate() now accepts an optional sizeparameter, as other file-like objects. Patch by Ryan Kelly.
• bpo-13458: Fix a memory leak in the ssl module when decoding a certificatewith a subjectAltName. Patch by Robert Xiao.
• bpo-13415: os.unsetenv() doesn’t ignore errors anymore.
• bpo-13245: sched.scheduler class constructor’s timefunc and delayfunctparameters are now optional. scheduler.enter and scheduler.enterabsmethods gained a new kwargs parameter. Patch contributed by Chris Clark.
• bpo-12328: Under Windows, refactor handling of Ctrl-C events and make_multiprocessing.win32.WaitForMultipleObjects interruptible when thewait_flag parameter is false. Patch by sbt.
• bpo-13322: Fix BufferedWriter.write() to ensure that BlockingIOError israised when the wrapped raw file is non-blocking and the write wouldblock. Previous code assumed that the raw write() would raiseBlockingIOError, but RawIOBase.write() is defined to returned None whenthe call would block. Patch by sbt.
• bpo-13358: HTMLParser now calls handle_data only once for each CDATA.
• bpo-4147: minidom’s toprettyxml no longer adds whitespace around a textnode when it is the only child of an element. Initial patch by DanKenigsberg.
• bpo-13374: The Windows bytes API has been deprecated in the os module. UseUnicode filenames instead of bytes filenames to not depend on the ANSIcode page anymore and to support any filename.
• bpo-13297: Use bytes type to send and receive binary data through XMLRPC.
• bpo-6397: Support “/dev/poll” polling objects in select module, underSolaris & derivatives.
• bpo-1745761: HTMLParser now correctly handles non-valid attributes,including adjacent and unquoted attributes. (See also: bpo-755670,bpo-13357, bpo-12629, bpo-1200313)
• bpo-13193: Fix distutils.filelist.FileList and packaging.manifest.Manifestunder Windows.
• bpo-13384: Remove unnecessary __future__ import in Lib/random.py
• bpo-13149: Speed up append-only StringIO objects.
• bpo-13373: multiprocessing.Queue.get() could sometimes block indefinitelywhen called with a timeout. Patch by Arnaud Ysmal.
• bpo-13254: Fix Maildir initialization so that maildir contents are readcorrectly.
• bpo-3067: locale.setlocale() now raises TypeError if the second argumentis an invalid iterable. Its documentation and docstring were also updated.Initial patch by Jyrki Pulliainen.
• bpo-13140: Fix the daemon_threads attribute of ThreadingMixIn.
• bpo-13339: Fix compile error in posixmodule.c due to missing semicolon.Thanks to Robert Xiao.
• Byte compilation in packaging is now isolated from the calling Python -Bor -O options, instead of being disallowed under -B or buggy under -O.
• bpo-10570: curses.putp() and curses.tparm() are now expecting a bytestring, instead of a Unicode string.
• bpo-13295: http.server now produces valid HTML 4.01 strict.
• bpo-2892: preserve iterparse events in case of SyntaxError.
• bpo-13287: urllib.request and urllib.error now contains an __all__attribute to expose only relevant classes and functions. Patch by FlorentXicluna.
• bpo-670664: Fix HTMLParser to correctly handle the content of<script>...</script> and<style>...</style>.
• bpo-10817: Fix urlretrieve function to raise ContentTooShortError evenwhen reporthook is None. Patch by Jyrki Pulliainen.
• Fix the xmlrpc.client user agent to return something similar tourllib.request user agent: “Python-xmlrpc/3.3”.
• bpo-13293: Better error message when trying to marshal bytes usingxmlrpc.client.
• bpo-13291: NameError in xmlrpc package.
• bpo-13258: Use callable() built-in in the standard library.
• bpo-13273: fix a bug that prevented HTMLParser to properly detect sometags when strict=False.
• bpo-11183: Add finer-grained exceptions to the ssl module, so that youdon’t have to inspect the exception’s attributes in the common case.
• bpo-13216: Add cp65001 codec, the Windows UTF-8 (CP_UTF8).
• bpo-13226: Add RTLD_xxx constants to the os module. These constants can beused with sys.setdlopenflags().
• bpo-10278: Add clock_getres(), clock_gettime() and CLOCK_xxx constants tothe time module. time.clock_gettime(time.CLOCK_MONOTONIC) provides amonotonic clock
• bpo-10332: multiprocessing: fix a race condition when a Pool is closedbefore all tasks have completed.
• bpo-13255: wrong docstrings in array module.
• bpo-8540: Remove deprecated Context._clamp attribute in Decimal module.
• bpo-13235: Added DeprecationWarning to logging.warn() method and function.
• bpo-9168: now smtpd is able to bind privileged port.
• bpo-12529: fix cgi.parse_header issue on strings with double-quotes andsemicolons together. Patch by Ben Darnell and Petri Lehtinen.
• bpo-13227: functools.lru_cache() now has a option to distinguish callswith different argument types.
• bpo-6090: zipfile raises a ValueError when a document with a timestampearlier than 1980 is provided. Patch contributed by Petri Lehtinen.
• bpo-13150: sysconfig no longer parses the Makefile and config.h files whenimported, instead doing it at build time. This makes importing sysconfigfaster and reduces Python startup time by 20%.
• bpo-12448: smtplib now flushes stdout while runningpython-msmtplibin order to display the prompt correctly.
• bpo-12454: The mailbox module is now using ASCII, instead of the localeencoding, to read and write .mh_sequences files.
• bpo-13194: zlib.compressobj().copy() and zlib.decompressobj().copy() arenow available on Windows.
• bpo-1673007: urllib.request now supports HEAD request via new methodargument. Patch contributions by David Stanek, Patrick Westerhoff and EzioMelotti.
• bpo-12386: packaging does not fail anymore when writing the RESOURCESfile.
• bpo-13158: Fix decoding and encoding of GNU tar specific base-256 numberfields in tarfile.
• bpo-13025: mimetypes is now reading MIME types using the UTF-8 encoding,instead of the locale encoding.
• bpo-10653: On Windows, use strftime() instead of wcsftime() becausewcsftime() doesn’t format time zone correctly.
• bpo-13150: The tokenize module doesn’t compile large regular expressionsat startup anymore.
• bpo-11171: Fix distutils.sysconfig.get_makefile_filename when Python wasconfigured with different prefix and exec-prefix.
• bpo-11254: Teach distutils and packaging to compile .pyc and .pyo files inPEP 3147-compliant __pycache__ directories.
• bpo-7367: Fix pkgutil.walk_paths to skip directories whose contents cannotbe read.
• bpo-3163: The struct module gets new format characters ‘n’ and ‘N’supporting C integer typesssize_t andsize_t, respectively.
• bpo-13099: Fix sqlite3.Cursor.lastrowid under a Turkish locale. Reportedand diagnosed by Thomas Kluyver.
• bpo-13087: BufferedReader.seek() now always raises UnsupportedOperation ifthe underlying raw stream is unseekable, even if the seek could besatisfied using the internal buffer. Patch by John O’Connor.
• bpo-7689: Allow pickling of dynamically created classes when theirmetaclass is registered with copyreg. Patch by Nicolas M. Thiéry andCraig Citro.
• bpo-13034: When decoding some SSL certificates, the subjectAltNameextension could be unreported.
• bpo-12306: Expose the runtime version of the zlib C library as a constant,ZLIB_RUNTIME_VERSION, in the zlib module. Patch by Torsten Landschoff.
• bpo-12959: Add collections.ChainMap to collections.__all__.
• bpo-8933: distutils’ PKG-INFO files and packaging’s METADATA files willnow correctly report Metadata-Version: 1.1 instead of 1.0 if a Classifieror Download-URL field is present.
• bpo-12567: Add curses.unget_wch() function. Push a character so the nextget_wch() will return it.
• bpo-9561: distutils and packaging now writes egg-info files using UTF-8,instead of the locale encoding.
• bpo-8286: The distutils command sdist will print a warning message insteadof crashing when an invalid path is given in the manifest template.
• bpo-12841: tarfile unnecessarily checked the existence of numerical userand group ids on extraction. If one of them did not exist the respectiveid of the current user (i.e. root) was used for the file and ownershipinformation was lost.
• bpo-12888: Fix a bug in HTMLParser.unescape that prevented it to escapemore than 128 entities. Patch by Peter Otten.
• bpo-12878: Expose a __dict__ attribute on io.IOBase and its subclasses.
• bpo-12494: On error, call(), check_call(), check_output() andgetstatusoutput() functions of the subprocess module now kill the process,read its status (to avoid zombis) and close pipes.
• bpo-12720: Expose low-level Linux extended file attribute functions in os.
• bpo-10946: The distutils commands bdist_dumb, bdist_wininst and bdist_msinow respect a –skip-build option given to bdist. The packaging commandswere fixed too.
• bpo-12847: Fix a crash with negative PUT and LONG_BINPUT arguments in theC pickle implementation.
• bpo-11564: Avoid crashes when trying to pickle huge objects or containers(more than 2**31 items). Instead, in most cases, an OverflowError israised.
• bpo-12287: Fix a stack corruption in ossaudiodev module when the FD isgreater than FD_SETSIZE.
• bpo-12839: Fix crash in zlib module due to version mismatch. Fix byRichard M. Tew.
• bpo-9923: The mailcap module now correctly uses the platform pathseparator for the MAILCAP environment variable on non-POSIX platforms.
• bpo-12835: Follow up to #6560 that unconditionally prevents use of theunencrypted sendmsg/recvmsg APIs on SSL wrapped sockets. Patch by DavidWatson.
• bpo-12803: SSLContext.load_cert_chain() now accepts a password argument tobe used if the private key is encrypted. Patch by Adam Simpkins.
• bpo-11657: Fix sending file descriptors over 255 over a multiprocessingPipe.
• bpo-12811: tabnanny.check() now promptly closes checked files. Patch byAnthony Briggs.
• bpo-6560: The sendmsg/recvmsg API is now exposed by the socket module whenprovided by the underlying platform, supporting processing of ancillarydata in pure Python code. Patch by David Watson and Heiko Wundram.
• bpo-12326: On Linux, sys.platform doesn’t contain the major versionanymore. It is now always ‘linux’, instead of ‘linux2’ or ‘linux3’depending on the Linux version used to build Python.
• bpo-12213: Fix a buffering bug with interleaved reads and writes thatcould appear on BufferedRandom streams.
• bpo-12778: Reduce memory consumption when JSON-encoding a large containerof many small objects.
• bpo-12650: Fix a race condition where a subprocess.Popen could leakresources (FD/zombie) when killed at the wrong time.
• bpo-12744: Fix inefficient representation of integers between 2**31 and2**63 on systems with a 64-bit C “long”.
• bpo-12646: Add an ‘eof’ attribute to zlib.Decompress, to make it easier todetect truncated input streams.
• bpo-11513: Fix exception handlingtarfile.TarFile.gzopen() when thefile cannot be opened.
• bpo-12687: Fix a possible buffering bug when unpickling text mode(protocol 0, mostly) pickles.
• bpo-10087: Fix the html output format of the calendar module.
• bpo-13121: add support for inplace math operators to collections.Counter.
• Add support for unary plus and unary minus to collections.Counter.
• bpo-12683: urlparse updated to include svn as schemes that uses relativepaths. (svn from 1.5 onwards support relative path).
• bpo-12655: Expose functions from sched.h in the os module: sched_yield(),sched_setscheduler(), sched_getscheduler(), sched_setparam(),sched_get_min_priority(), sched_get_max_priority(),sched_rr_get_interval(), sched_getaffinity(), sched_setaffinity().
• Add ThreadError to threading.__all__.
• bpo-11104: Fix the behavior of distutils’ sdist command withmanually-maintained MANIFEST files. (See also: bpo-8688)
• bpo-11281: smtplib.STMP gets source_address parameter, which adds theability to bind to specific source address on a machine with multipleinterfaces. Patch by Paulo Scardine.
• bpo-12464: tempfile.TemporaryDirectory.cleanup() should not followsymlinks: fix it. Patch by Petri Lehtinen.
• bpo-8887: “pydoc somebuiltin.somemethod” (orhelp(‘somebuiltin.somemethod’) in Python code) now finds the doc of themethod.
• bpo-10968: Remove indirection in threading. The public names (Event,Condition, etc.) used to be factory functions returning instances ofhidden classes (_Event, _Condition, etc.), because (if Guido recallscorrectly) this code pre-dates the ability to subclass extension types.It is now possible to inherit from these classes, without having to importthe private underscored names like multiprocessing did.
• bpo-9723: Add shlex.quote functions, to escape filenames and commandlines.
• bpo-12603: Fix pydoc.synopsis() on files with non-negative st_mtime.
• bpo-12514: Use try/finally to assure the timeit module restores garbagecollections when it is done.
• bpo-12607: In subprocess, fix issue where if stdin, stdout or stderr isgiven as a low fd, it gets overwritten.
• bpo-12576: Fix urlopen behavior on sites which do not send (or obfuscates)Connection:close header.
• bpo-12560: Build libpython.so on OpenBSD. Patch by Stefan Sperling.
• bpo-1813: Fix codec lookup under Turkish locales.
• bpo-12591: Improve support of “universal newlines” in the subprocessmodule: the piped streams can now be properly read from or written to.
• bpo-12591: Allow io.TextIOWrapper to work with raw IO objects (without aread1() method), and add awrite_through parameter to mandate unbufferedwrites.
• bpo-10883: Fix socket leaks in urllib.request when using FTP.
• bpo-12592: Make Python build on OpenBSD 5 (and future major releases).
• bpo-12372: POSIX semaphores are broken on AIX: don’t use them.
• bpo-12551: Provide a get_channel_binding() method on SSL sockets so as toget channel binding data for the current SSL session (only the“tls-unique” channel binding is implemented). This allows theimplementation of certain authentication mechanisms such asSCRAM-SHA-1-PLUS. Patch by Jacek Konieczny.
• bpo-665194: email.utils now has format_datetime and parsedate_to_datetimefunctions, allowing for round tripping of RFC2822 format dates.
• bpo-12571: Add a plat-linux3 directory mirroring the plat-linux2directory, so that “import DLFCN” and other similar imports work on Linux3.0.
• bpo-7484: smtplib no longer puts <> around addresses in VRFY and EXPNcommands; they aren’t required and in fact postfix doesn’t support thatform.
• bpo-12273: Remove ast.__version__. AST changes can be accounted for bychecking sys.version_info or sys._mercurial.
• Silence spurious “broken pipe” tracebacks when shutting down aProcessPoolExecutor.
• Fix potential resource leaks in concurrent.futures.ProcessPoolExecutor byjoining all queues and processes when shutdown() is called.
• bpo-11603: Fix a crash when __str__ is rebound as __repr__. Patch byAndreas Stührk.
• bpo-11321: Fix a crash with multiple imports of the _pickle module whenembedding Python. Patch by Andreas Stührk.
• bpo-6755: Add get_wch() method to curses.window class. Patch by IñigoSerna.
• Add cgi.closelog() function to close the log file.
• bpo-12502: asyncore: fix polling loop with AF_UNIX sockets.
• bpo-4376: ctypes now supports nested structures in a endian different thanthe parent structure. Patch by Vlad Riscutia.
• Raise ValueError when attempting to set the _CHUNK_SIZE attribute of aTextIOWrapper to a huge value, not TypeError.
• bpo-12504: Close file handles in a timely manner in packaging.database.This fixes a bug with the remove (uninstall) feature on Windows.
• bpo-12169: Factor out code used by various packaging commands to make HTTPPOST requests, and make sure it uses CRLF. (See also: bpo-10510)
• bpo-12016: Multibyte CJK decoders now resynchronize faster. They onlyignore the first byte of an invalid byte sequence. For example,b’xffn’.decode(‘gb2312’, ‘replace’) gives ‘ufffdn’ instead of‘ufffd’.
• bpo-12459: time.sleep() now raises a ValueError if the sleep length isnegative, instead of an infinite sleep on Windows or raising an IOError onLinux for example, to have the same behaviour on all platforms.
• bpo-12451: pydoc: html_getfile() now uses tokenize.open() to supportPython scripts using a encoding different than UTF-8 (read the codingcookie of the script).
• bpo-12493: subprocess: Popen.communicate() now also handles EINTR errorsif the process has only one pipe.
• bpo-12467: warnings: fix a race condition if a warning is emitted atshutdown, if globals()[‘__file__’] is None.
• bpo-12451: pydoc: importfile() now opens the Python script in binary mode,instead of text mode using the locale encoding, to avoid encoding issues.
• bpo-12451: runpy: run_path() now opens the Python script in binary mode,instead of text mode using the locale encoding, to support other encodingsthan UTF-8 (scripts using the coding cookie).
• bpo-12451: xml.dom.pulldom: parse() now opens files in binary mode insteadof the text mode (using the locale encoding) to avoid encoding issues.
• bpo-12147: Adjust the new-in-3.2 smtplib.send_message method for betterconformance to the RFCs: correctly handle Sender and Resent- headers.
• bpo-12352: Fix a deadlock in multiprocessing.Heap when a block is freed bythe garbage collector while the Heap lock is held.
• bpo-12462: time.sleep() now immediately calls the (Python) signal handlerif it is interrupted by a signal, instead of having to wait until the nextinstruction.
• bpo-12442: new shutil.disk_usage function, providing total, used and freedisk space statistics.
• bpo-12451: The XInclude default loader of xml.etree now decodes files fromUTF-8 instead of the locale encoding if the encoding is not specified. Itnow also opens XML files for the parser in binary mode instead of the textmode to avoid encoding issues.
• bpo-12451: doctest.debug_script() doesn’t create a temporary file anymoreto avoid encoding issues.
• bpo-12451: pydoc.synopsis() now reads the encoding cookie if available, toread the Python script from the right encoding.
• bpo-12451: distutils now opens the setup script in binary mode to read theencoding cookie, instead of opening it in UTF-8.
• bpo-9516: On Mac OS X, change Distutils to no longer globally attempt tocheck or set the MACOSX_DEPLOYMENT_TARGET environment variable for theinterpreter process. This could cause failures in non-Distutilssubprocesses and was unreliable since tests or user programs could modifythe interpreter environment after Distutils set it. Instead, haveDistutils set the deployment target only in the environment of each buildsubprocess. It is still possible to globally override the default bysetting MACOSX_DEPLOYMENT_TARGET before launching the interpreter; itsvalue must be greater or equal to the default value, the value with whichthe interpreter was built. Also, implement the same handling inpackaging.
• bpo-12422: In the copy module, don’t store objects that are their own copyin the memo dict.
• bpo-12303: Add sigwaitinfo() and sigtimedwait() to the signal module.
• bpo-12404: Remove C89 incompatible code from mmap module. Patch by AkiraKitada.
• bpo-1874: email now detects and reports as a defect the presence of anyCTE other than 7bit, 8bit, or binary on a multipart.
• bpo-12383: Fix subprocess module with env={}: don’t copy the environmentvariables, start with an empty environment.
• bpo-11637: Fix support for importing packaging setup hooks from theproject directory.
• bpo-6771: Moved the curses.wrapper function from the single-functionwrapper module into __init__, eliminating the module. Since __init__ wasalready importing the function to curses.wrapper, there is no API change.
• bpo-11584: email.header.decode_header no longer fails if the header passedto it is a Header object, and Header/make_header no longer fail if givenbinary unknown-8bit input.
• bpo-11700: mailbox proxy object close methods can now be called multipletimes without error.
• bpo-11767: Correct file descriptor leak in mailbox’s __getitem__ method.
• bpo-12133: AbstractHTTPHandler.do_open() of urllib.request closes the HTTPconnection if its getresponse() method fails with a socket error. Patchwritten by Ezio Melotti.
• bpo-12240: Allow multiple setup hooks in packaging’s setup.cfg files.Original patch by Erik Bray.
• bpo-9284: Allow inspect.findsource() to find the source of doctestfunctions.
• bpo-11595: Fix assorted bugs in packaging.util.cfg_to_args, acompatibility helper for the distutils-packaging transition. Originalpatch by Erik Bray.
• bpo-12287: In ossaudiodev, check that the device isn’t closed in severalmethods.
• bpo-12009: Fixed regression in netrc file comment handling.
• bpo-12246: Warn and fail when trying to install a third-party project froman uninstalled Python (built in a source checkout). Original patch byTshepang Lekhonkhobe.
• bpo-10694: zipfile now ignores garbage at the end of a zipfile.
• bpo-12283: Fixed regression in smtplib quoting of leading dots in DATA.
• bpo-10424: Argparse now includes the names of the missing requiredarguments in the missing arguments error message.
• bpo-12168: SysLogHandler now allows NUL termination to be controlled usinga new ‘append_nul’ attribute on the handler.
• bpo-11583: Speed up os.path.isdir on Windows by using GetFileAttributesinstead of os.stat.
• bpo-12021: Make mmap’s read() method argument optional. Patch by PetriLehtinen.
• bpo-9205: concurrent.futures.ProcessPoolExecutor now detects killedchildren and raises BrokenProcessPool in such a situation. Previously itwould reliably freeze/deadlock.
• bpo-12040: Expose a new attributesentinel on instances ofmultiprocessing.Process. Also, fix Process.join() to not use pollinganymore, when given a timeout.
• bpo-11893: Remove obsolete internal wrapper classSSLFakeFile in thesmtplib module. Patch by Catalin Iacob.
• bpo-12080: Fix a Decimal.power() case that took an unreasonably long timeto compute.
• bpo-12221: Remove __version__ attributes from pyexpat, pickle, tarfile,pydoc, tkinter, and xml.parsers.expat. This were useless version constantsleft over from the Mercurial transition
• Named tuples now work correctly with vars().
• bpo-12085: Fix an attribute error in subprocess.Popen destructor if theconstructor has failed, e.g. because of an undeclared keyword argument.Patch written by Oleg Oshmyan.
• bpo-12028: Make threading._get_ident() public, rename it tothreading.get_ident() and document it. This function was already usedusing _thread.get_ident().
• bpo-12171: IncrementalEncoder.reset() of CJK codecs (multibytecodec) callsencreset() instead of decreset().
• bpo-12218: Removed wsgiref.egg-info.
• bpo-12196: Add pipe2() to the os module.
• bpo-985064: Make plistlib more resilient to faulty input plists. Patch byMher Movsisyan.
• bpo-1625: BZ2File and bz2.decompress() now support multi-stream files.Initial patch by Nir Aides.
• bpo-12175: BufferedReader.read(-1) now calls raw.readall() if available.
• bpo-12175: FileIO.readall() now only reads the file position and sizeonce.
• bpo-12175: RawIOBase.readall() now returns None if read() returns None.
• bpo-12175: FileIO.readall() now raises a ValueError instead of an IOErrorif the file is closed.
• bpo-11109: New service_action method for BaseServer, used by ForkingMixinclass for cleanup. Initial Patch by Justin Warkentin.
• bpo-12045: Avoid duplicate execution of command inctypes.util._get_soname(). Patch by Sijin Joseph.
• bpo-10818: Remove the Tk GUI and the serve() function of the pydoc module,pydoc -g has been deprecated in Python 3.2 and it has a new enhanced webserver.
• bpo-1441530: In imaplib, read the data in one chunk to speed up largereads and simplify code.
• bpo-12070: Fix the Makefile parser of the sysconfig module to handlecorrectly references to “bogus variable” (e.g. “prefix=$/opt/python”).
• bpo-12100: Don’t reset incremental encoders of CJK codecs at each call totheir encode() method anymore, but continue to call the reset() method ifthe final argument is True.
• bpo-12049: Add RAND_bytes() and RAND_pseudo_bytes() functions to the sslmodule.
• bpo-6501: os.device_encoding() returns None on Windows if the applicationhas no console.
• bpo-12105: Add O_CLOEXEC to the os module.
• bpo-12079: Decimal(‘Infinity’).fma(Decimal(‘0’),(3.91224318126786e+19+0j)) now raises TypeError (reflecting the invalidtype of the 3rd argument) rather than Decimal.InvalidOperation.
• bpo-12124: zipimport doesn’t keep a reference to zlib.decompress() anymoreto be able to unload the module.
• Add the packaging module, an improved fork of distutils (also known asdistutils2).
• bpo-12065: connect_ex() on an SSL socket now returns the original errnowhen the socket’s timeout expires (it used to return None).
• bpo-8809: The SMTP_SSL constructor and SMTP.starttls() now support passingacontext argument pointing to an ssl.SSLContext instance. Patch byKasun Herath.
• bpo-9516: avoid errors in sysconfig when MACOSX_DEPLOYMENT_TARGET is setin shell. (See also: bpo-9516)
• bpo-8650: Make zlib module 64-bit clean. compress(), decompress() andtheir incremental counterparts now raise OverflowError if given an inputlarger than 4GB, instead of silently truncating the input and returning anincorrect result.
• bpo-12050: zlib.decompressobj().decompress() now clears theunconsumed_tail attribute when called without a max_length argument.
• bpo-12062: Fix a flushing bug when doing a certain type of I/O sequence ona file opened in read+write mode (namely: reading, seeking a bit forward,writing, then seeking before the previous write but still within buffereddata, and writing again).
• bpo-9971: Write an optimized implementation of BufferedReader.readinto().Patch by John O’Connor.
• bpo-11799: urllib.request Authentication Handlers will raise a ValueErrorwhen presented with an unsupported Authentication Scheme. Patchcontributed by Yuval Greenfield.
• bpo-10419: build_scripts command of distutils handles correctly non-ASCIIpath (path to the Python executable). Open and write the script in binarymode, but ensure that the shebang is decodable from UTF-8 and from theencoding of the script. (See also: bpo-6011)
• bpo-8498: In socket.accept(), allow to specify 0 as a backlog value inorder to accept exactly one connection. Patch by Daniel Evers.
• bpo-12011: signal.signal() and signal.siginterrupt() raise an OSError,instead of a RuntimeError: OSError has an errno attribute.
• bpo-3709: add a flush_headers method to BaseHTTPRequestHandler, whichmanages the sending of headers to output stream and flushing the internalheaders buffer. Patch contribution by Andrew Schaaf
• bpo-11743: Rewrite multiprocessing connection classes in pure Python.
• bpo-11164: Stop trying to use _xmlplus in the xml module.
• bpo-11888: Add log2 function to math module. Patch written by MarkDickinson.
• bpo-12012: ssl.PROTOCOL_SSLv2 becomes optional.
• bpo-8407: The signal handler writes the signal number as a single byteinstead of a nul byte into the wakeup file descriptor. So it is possibleto wait more than one signal and know which signals were raised.
• bpo-8407: Add pthread_kill(), sigpending() and sigwait() functions to thesignal module.
• bpo-11927: SMTP_SSL now uses port 465 by default as documented. Patch byKasun Herath.
• bpo-12002: ftplib’s abort() method raises TypeError.
• bpo-11916: Add a number of MacOSX specific definitions to the errnomodule. Patch by Pierre Carrier.
• bpo-11999: fixed sporadic sync failure mailbox.Maildir due to its tryingto detect mtime changes by comparing to the system clock instead of to theprevious value of the mtime.
• bpo-11072: added MLSD command (RFC-3659) support to ftplib.
• bpo-8808: The IMAP4_SSL constructor now allows passing an SSLContextparameter to control parameters of the secure channel. Patch by SijinJoseph.
• ntpath.samefile failed to notice that “a.txt” and “A.TXT” refer to thesame file on Windows XP. As noticed inissue #10684.
• bpo-12000: When a SSL certificate has a subjectAltName without any dNSNameentry, ssl.match_hostname() should use the subject’s commonName. Patch byNicolas Bareil.
• bpo-10775: assertRaises, assertRaisesRegex, assertWarns, andassertWarnsRegex now accept a keyword argument ‘msg’ when used as contextmanagers. Initial patch by Winston Ewert.
• bpo-10684: shutil.move used to delete a folder on case insensitivefilesystems when the source and destination name where the same except forthe case.
• bpo-11647: objects created using contextlib.contextmanager now supportmore than one call to the function when used as a decorator. Initial patchby Ysj Ray.
• bpo-11930: Removed deprecated time.accept2dyear variable. Removed year >=1000 restriction from datetime.strftime.
• logging: don’t define QueueListener if Python has no thread support.
• functools.cmp_to_key() now works with collections.Hashable().
• bpo-11277: mmap.mmap() calls fcntl(fd, F_FULLFSYNC) on Mac OS X to getaround a mmap bug with sparse files. Patch written by Steffen DaodeNurpmeso.
• bpo-8407: Add signal.pthread_sigmask() function to fetch and/or change thesignal mask of the calling thread.
• bpo-11858: configparser.ExtendedInterpolation expected lower-case sectionnames.
• bpo-11324: ConfigParser(interpolation=None) now works correctly.
• bpo-11811: ssl.get_server_certificate() is now IPv6-compatible. Patch byCharles- François Natali.
• bpo-11763: don’t use difflib in TestCase.assertMultiLineEqual if thestrings are too long.
• bpo-11236: getpass.getpass responds to ctrl-c or ctrl-z on terminal.
• bpo-11856: Speed up parsing of JSON numbers.
• bpo-11005: threading.RLock()._release_save() raises a RuntimeError if thelock was not acquired.
• bpo-11258: Speed up ctypes.util.find_library() under Linux by a factor of5 to 10. Initial patch by Jonas H.
• bpo-11382: Trivial system calls, such as dup() or pipe(), needn’t releasethe GIL. Patch by Charles-François Natali.
• bpo-11223: Add threading._info() function providing informations about thethread implementation.
• bpo-11731: simplify/enhance email parser/generator API by introducingpolicy objects.
• bpo-11768: The signal handler of the signal module only callsPy_AddPendingCall() for the first signal to fix a deadlock on reentrant orparallel calls. PyErr_SetInterrupt() writes also into the wake up file.
• bpo-11492: fix several issues with header folding in the email package.
• bpo-11852: Add missing imports and update tests.
• bpo-11875: collections.OrderedDict’s __reduce__ was temporarily mutatingthe object instead of just working on a copy.
• bpo-11467: Fix urlparse behavior when handling urls which contains schemespecific part only digits. Patch by Santoso Wijaya.
• collections.Counter().copy() now works correctly for subclasses.
• bpo-11474: Fix the bug with url2pathname() handling of ‘/C|/’ on Windows.Patch by Santoso Wijaya.
• bpo-11684: complete email.parser bytes API by adding BytesHeaderParser.
• The bz2 module now handles 4GiB+ input buffers correctly.
• bpo-9233: Fix json.loads(‘{}’) to return a dict (instead of a list), when_json is not available.
• bpo-11830: Remove unnecessary introspection code in the decimal module.
• bpo-11703: urllib2.geturl() does not return correct url when the originalurl contains #fragment.
• bpo-10019: Fixed regression in json module where an indent of 0 stoppedadding newlines and acted instead like ‘None’.
• bpo-11186: pydoc ignores a module if its name contains a surrogatecharacter in the index of modules.
• bpo-11815: Use a light-weight SimpleQueue for the result queue inconcurrent.futures.ProcessPoolExecutor.
• bpo-5162: Treat services like frozen executables to allow child spawningfrom multiprocessing.forking on Windows.
• logging.basicConfig now supports an optional ‘handlers’ argument taking aniterable of handlers to be added to the root logger. Additional parameterchecks were also added to basicConfig.
• bpo-11814: Fix likely typo in multiprocessing.Pool._terminate().
• bpo-11747: Fix range formatting in difflib.context_diff() anddifflib.unified_diff().
• bpo-8428: Fix a race condition in multiprocessing.Pool when terminatingworker processes: new processes would be spawned while the pool is beingshut down. Patch by Charles-François Natali.
• bpo-2650: re.escape() no longer escapes the ‘_’.
• bpo-11757: select.select() now raises ValueError when a negative timeoutis passed (previously, a select.error with EINVAL would be raised). Patchby Charles- François Natali.
• bpo-7311: fix html.parser to accept non-ASCII attribute values.
• bpo-11605: email.parser.BytesFeedParser was incorrectly convertingmultipart subparts with an 8-bit CTE into unicode instead of preservingthe bytes.
• bpo-1690608: email.util.formataddr is now RFC 2047 aware: it now has acharset parameter that defaults to utf-8 and is used as the charset forRFC 2047 encoding when the realname contains non-ASCII characters.
• bpo-10963: Ensure that subprocess.communicate() never raises EPIPE.
• bpo-10791: Implement missing method GzipFile.read1(), allowing GzipFile tobe wrapped in a TextIOWrapper. Patch by Nadeem Vawda.
• bpo-11707: Added a fast C version of functools.cmp_to_key(). Patch byFilip Gruszczyński.
• bpo-11688: Add sqlite3.Connection.set_trace_callback(). Patch by TorstenLandschoff.
• bpo-11746: Fix SSLContext.load_cert_chain() to accept elliptic curveprivate keys.
• bpo-5863: Rewrite BZ2File in pure Python, and allow it to accept file-likeobjects using a newfileobj constructor argument. Patch by NadeemVawda.
• unittest.TestCase.assertSameElements has been removed.
• sys.getfilesystemencoding() raises a RuntimeError if initfsencoding() wasnot called yet: detect bootstrap (startup) issues earlier.
• bpo-11393: Add the new faulthandler module.
• bpo-11618: Fix the timeout logic in threading.Lock.acquire() underWindows.
• Removed the ‘strict’ argument to email.parser.Parser, which has beendeprecated since Python 2.4.
• bpo-11256: Fix inspect.getcallargs on functions that take only keywordarguments.
• bpo-11696: Fix ID generation in msilib.
• itertools.accumulate now supports an optionalfunc argument for a user-supplied binary function.
• bpo-11692: Remove unnecessary demo functions in subprocess module.
• bpo-9696: Fix exception incorrectly raised by xdrlib.Packer.pack_int whentrying to pack a negative (in-range) integer.
• bpo-11675: multiprocessing.[Raw]Array objects created from an integer sizeare now zeroed on creation. This matches the behaviour specified by thedocumentation.
• bpo-7639: Fix short file name generation in bdist_msi
• bpo-11635: Don’t use polling in worker threads and processes launched byconcurrent.futures.
• bpo-5845: Automatically read readline configuration to enable completionin interactive mode.
• bpo-6811: Allow importlib to change a code object’s co_filename attributeto match the path to where the source code currently is, not where thecode object originally came from.
• bpo-8754: Have importlib use the repr of a module name in error messages.
• bpo-11591: Prevent “import site” from modifying sys.path when python wasstarted with -S.
• collections.namedtuple() now adds a _source attribute to the generatedclass. This make the source more accessible than the outdated “verbose”option which prints to stdout but doesn’t make the source stringavailable.
• bpo-11371: Mark getopt error messages as localizable. Patch by FilipGruszczyński.
• bpo-11333: Add __slots__ to collections ABCs.
• bpo-11628: cmp_to_key generated class should use __slots__.
• bpo-11666: let help() display named tuple attributes and methods thatstart with a leading underscore.
• bpo-11662: Make urllib and urllib2 ignore redirections if the scheme isnot HTTP, HTTPS or FTP (CVE-2011-1521).
• bpo-5537: Fix time2isoz() and time2netscape() functions ofhttplib.cookiejar for expiration year greater than 2038 on 32-bit systems.
• bpo-4391: Use proper gettext plural forms in optparse.
• bpo-11127: Raise a TypeError when trying to pickle a socket object.
• bpo-11563:Connection:close header is sent by requests usingURLOpener class which helps in closing of sockets after connection isover. Patch contributions by Jeff McNeil and Nadeem Vawda.
• bpo-11459: Abufsize value of 0 in subprocess.Popen() really createsunbuffered pipes, such that select() works properly on them.
• bpo-5421: Fix misleading error message when one of socket.sendto()’sarguments has the wrong type. Patch by Nikita Vetoshkin.
• bpo-10812: Add some extra posix functions to the os module.
• bpo-10979: unittest stdout buffering now works with class and module setupand teardown.
• bpo-11243: fix the parameter querying methods of Message to work if theheaders contain un-encoded non-ASCII data.
• bpo-11401: fix handling of headers with no value; this fixes a regressionrelative to Python2 and the result is now the same as it was in Python2.
• bpo-9298: base64 bodies weren’t being folded to line lengths less than 78,which was a regression relative to Python2. Unlike Python2, the last lineof the folded body now ends with a carriage return.
• bpo-11560: shutil.unpack_archive now correctly handles the formatparameter. Patch by Evan Dandrea.
• bpo-5870: Addsubprocess.DEVNULL constant.
• bpo-11133: fix two cases where inspect.getattr_static can trigger codeexecution. Patch by Andreas Stührk.
• bpo-11569: use absolute path to the sysctl command in multiprocessing toensure that it will be found regardless of the shell PATH. This ensuresthat multiprocessing.cpu_count works on default installs of MacOSX.
• bpo-11501: disutils.archive_utils.make_zipfile no longer fails if zlib isnot installed. Instead, the zipfile.ZIP_STORED compression is used tocreate the ZipFile. Patch by Natalia B. Bidart.
• bpo-11289:smtp.SMTP class is now a context manager so it can be used inawith statement. Contributed by Giampaolo Rodola.
• bpo-11554: Fixed support for Japanese codecs; previously the body outputencoding was not done if euc-jp or shift-jis was specified as the charset.
• bpo-11407:TestCase.run returns the result object used or created.Contributed by Janathan Hartley.
• bpo-11500: Fixed a bug in the OS X proxy bypass code for fully qualifiedIP addresses in the proxy exception list.
• bpo-11491: dbm.error is no longer raised when dbm.open is called with the“n” as the flag argument and the file exists. The behavior matches thedocumentation and general logic.
• bpo-1162477: Postel Principle adjustment to email date parsing: handle thefact that some non-compliant MUAs use ‘.’ instead of ‘:’ in time specs.
• bpo-11131: Fix sign of zero in decimal.Decimal plus and minus operationswhen the rounding mode is ROUND_FLOOR.
• bpo-9935: Speed up pickling of instances of user-defined classes.
• bpo-5622: Fix curses.wrapper to raise correct exception if cursesinitialization fails.
• bpo-11408: In threading.Lock.acquire(), only call gettimeofday() whenreally necessary. Patch by Charles-François Natali.
• bpo-11391: Writing to a mmap object created withmmap.PROT_READ|mmap.PROT_EXEC would segfault instead of raising aTypeError. Patch by Charles-François Natali.
• bpo-9795: add context manager protocol support for nntplib.NNTP class.
• bpo-11306: mailbox in certain cases adapts to an inability to open certainfiles in read-write mode. Previously it detected this by checking forEACCES, now it also checks for EROFS.
• bpo-11265: asyncore now correctly handles EPIPE, EBADF and EAGAIN errorson accept(), send() and recv().
• bpo-11377: Deprecate platform.popen() and reimplement it with os.popen().
• bpo-8513: On UNIX, subprocess supports bytes command string.
• bpo-10866: Add socket.sethostname(). Initial patch by Ross Lagerwall.
• bpo-11140: Lock.release() now raises a RuntimeError when attempting torelease an unacquired lock, as claimed in the threading documentation. The_thread.error exception is now an alias of RuntimeError. Patch by FilipGruszczyński. Patch for _dummy_thread by Aymeric Augustin.
• bpo-8594: ftplib now provides a source_address parameter to specify which(address, port) to bind to before connecting.
• bpo-11326: Add the missing connect_ex() implementation for SSL sockets,and make it work for non-blocking connects.
• bpo-11297: Add collections.ChainMap().
• bpo-10755: Add the posix.flistdir() function. Patch by Ross Lagerwall.
• bpo-4761: Add the*at() family of functions (openat(), etc.) to theposix module. Patch by Ross Lagerwall.
• bpo-7322: Trying to read from a socket’s file-like object after a timeoutoccurred now raises an error instead of silently losing data.
• bpo-11291: poplib.POP no longer suppresses errors on quit().
• bpo-11177: asyncore’s create_socket() arguments can now be omitted.
• bpo-6064: Add adaemon keyword argument to the threading.Thread andmultiprocessing.Process constructors in order to override the defaultbehaviour of inheriting the daemonic property from the currentthread/process.
• bpo-10956: Buffered I/O classes retry reading or writing after a signalhas arrived and the handler returned successfully.
• bpo-10784: New os.getpriority() and os.setpriority() functions.
• bpo-11114: Fix catastrophic performance of tell() on text files (up to1000x faster in some cases). It is still one to two order of magnitudesslower than binary tell().
• bpo-10882: Add os.sendfile function.
• bpo-10868: Allow usage of the register method of an ABC as a classdecorator.
• bpo-11224: Fixed a regression in tarfile that affected the file-likeobjects returned by TarFile.extractfile() regarding performance, memoryconsumption and failures with the stream interface.
• bpo-10924: Adding salt and Modular Crypt Format to crypt library. Movedold C wrapper to _crypt, and added a Python wrapper with enhanced saltgeneration and simpler API for password generation.
• bpo-11074: Make ‘tokenize’ so it can be reloaded.
• bpo-11085: Moved collections abstract base classes into a separate modulecalled collections.abc, following the pattern used by importlib.abc. Forbackwards compatibility, the names are imported into the collectionsmodule.
• bpo-4681: Allow mmap() to work on file sizes and offsets larger than 4GB,even on 32-bit builds. Initial patch by Ross Lagerwall, adapted for32-bit Windows.
• bpo-11169: compileall module uses repr() to format filenames and paths toescape surrogate characters and show spaces.
• bpo-11089: Fix performance issue limiting the use of ConfigParser() withlarge config files.
• bpo-10276: Fix the results of zlib.crc32() and zlib.adler32() on bufferslarger than 4GB. Patch by Nadeem Vawda.
• bpo-11388: Added a clear() method to MutableSequence
• bpo-11174: Add argparse.MetavarTypeHelpFormatter, which uses type namesfor the names of optional and positional arguments in help messages.
• bpo-9348: Raise an early error if argparse nargs and metavar don’t match.
• bpo-9026: Fix order of argparse sub-commands in help messages.
• bpo-9347: Fix formatting for tuples in argparse type= error messages.
• bpo-12191: Added shutil.chown() to change user and/or group owner of agiven path also specifying their names.
• bpo-13988: The _elementtree accelerator is used whenever available. Nowxml.etree.cElementTree becomes a deprecated alias to ElementTree.

Build¶

• bpo-6807: Run msisupport.mak earlier.
• bpo-10580: Minor grammar change in Windows installer.
• bpo-13326: Clean __pycache__ directories correctly on OpenBSD.
• PEP 393: the configure option –with-wide-unicode is removed.
• bpo-12852: Set _XOPEN_SOURCE to 700, instead of 600, to get POSIX 2008functions on OpenBSD (e.g. fdopendir).
• bpo-11863: Remove support for legacy systems deprecated in Python 3.2(following PEP 11). These systems are systems using Mach C Threads, SunOSlightweight processes, GNU pth threads and IRIX threads.
• bpo-8746: Correct faulty configure checks so that os.chflags() andos.lchflags() are once again built on systems that support these functions(BSD and OS X). Also add new stat file flags for OS X (UF_HIDDEN andUF_COMPRESSED).
• bpo-10645: Installing Python no longer creates aPython-X.Y.Z-pyX.Y.egg-info file in the lib-dynload directory.
• Do not accidentally include the directory containing sqlite.h twice whenbuilding sqlite3.
• bpo-11217: For 64-bit/32-bit Mac OS X universal framework builds, ensure“make install” creates symlinks in –prefix bin for the “-32” files in theframework bin directory like the installer does.
• bpo-11347: Use –no-as-needed when linking libpython3.so.
• bpo-11411: Fix ‘make DESTDIR=’ with a relative destination.
• bpo-11268: Prevent Mac OS X Installer failure if Documentation package hadpreviously been installed.
• bpo-11495: OSF support is eliminated. It was deprecated in Python 3.2.

IDLE¶

• bpo-14409: IDLE now properly executes commands in the Shell window when itcannot read the normal config files on startup and has to use the built-indefault key bindings. There was previously a bug in one of the defaults.
• IDLE can be launched as python -m idlelib
• bpo-3573: IDLE hangs when passing invalid command line args(directory(ies) instead of file(s)) (Patch by Guilherme Polo)
• bpo-14200: IDLE shell crash on printing non-BMP unicode character.
• bpo-5219: Prevent event handler cascade in IDLE.
• bpo-964437: Make IDLE help window non-modal. Patch by Guilherme Polo andRoger Serwy.
• bpo-13933: IDLE auto-complete did not work with some imported module, likehashlib. (Patch by Roger Serwy)
• bpo-13506: Add ‘’ to path for IDLE Shell when started and restarted withRestart Shell. Original patches by Marco Scataglini and Roger Serwy.
• bpo-4625: If IDLE cannot write to its recent file or breakpoint files,display a message popup and continue rather than crash. Original patch byRoger Serwy.
• bpo-8641: Update IDLE 3 syntax coloring to recognize b”..” and not u”..”.Patch by Tal Einat.
• bpo-13296: Fix IDLE to clear compile __future__ flags on shell restart.(Patch by Roger Serwy)
• bpo-9871: Prevent IDLE 3 crash when given byte stings with invalid hexescape sequences, like b’x0’. (Original patch by Claudiu Popa.)
• bpo-12636: IDLE reads the coding cookie when executing a Python script.
• bpo-12540: Prevent zombie IDLE processes on Windows due to changes inos.kill().
• bpo-12590: IDLE editor window now always displays the first line whenopening a long file. With Tk 8.5, the first line was hidden.
• bpo-11088: don’t crash when using F5 to run a script in IDLE on MacOSXwith Tk 8.5.
• bpo-1028: Tk returns invalid Unicode null in %A: UnicodeDecodeError. WithTk < 8.5 _tkinter.c:PythonCmd() raised UnicodeDecodeError, caused IDLE toexit. Converted to valid Unicode null in PythonCmd().
• bpo-11718: IDLE’s open module dialog couldn’t find the __init__.py file ina package.

Tools/Demos¶

• bpo-14053: patchcheck.py (“make patchcheck”) now works with MQ patches.Patch by Francisco Martín Brugué.
• bpo-13930: 2to3 is now able to write its converted output files to anotherdirectory tree as well as copying unchanged files and altering the filesuffix. See its new -o, -W and –add-suffix options. This makes it moreuseful in many automated code translation workflows.
• bpo-13628: python-gdb.py is now able to retrieve more frames in the Pythontraceback if Python is optimized.
• bpo-11996: libpython (gdb), replace “py-bt” command by “py-bt-full” andadd a smarter “py-bt” command printing a classic Python traceback.
• bpo-11179: Make ccbench work under Python 3.1 and 2.7 again.
• bpo-10639: reindent.py no longer converts newlines and will raise an errorif attempting to convert a file with mixed newlines. “–newline” optionadded to specify new line character.

Library¶

• bpo-16847: Fixed improper use of _PyUnicode_CheckConsistency() innon-pydebug builds. Several extension modules now compile cleanly whenassert()s are enabled in standard builds (-DDEBUG flag).
• bpo-13840: The error message produced by ctypes.create_string_buffer whengiven a Unicode string has been fixed.
• bpo-9975: socket: Fix incorrect use of flowinfo and scope_id. Patch byVilmos Nebehaj.
• bpo-7777: socket: Add Reliable Datagram Sockets (PF_RDS) support.
• bpo-13159: FileIO and BZ2Compressor/BZ2Decompressor now use a linear-timebuffer growth strategy instead of a quadratic-time one.
• bpo-10141: socket: Add SocketCAN (PF_CAN) support. Initial patch byMatthias Fuchs, updated by Tiago Gonçalves.
• bpo-13070: Fix a crash when a TextIOWrapper caught in a reference cyclewould be finalized after the reference to its underlying BufferedRWPair’swriter got cleared by the GC.
• bpo-12881: ctypes: Fix segfault with large structure field names.
• bpo-13058: ossaudiodev: fix a file descriptor leak on error. Patch byThomas Jarosch.
• bpo-13013: ctypes: Fix a reference leak in PyCArrayType_from_ctype. Thanksto Suman Saha for finding the bug and providing a patch.
• bpo-13022: Fix: _multiprocessing.recvfd() doesn’t check that filedescriptor was actually received.
• bpo-1172711: Add ‘long long’ support to the array module. Initial patch byOren Tirosh and Hirokazu Yamamoto.
• bpo-12483: ctypes: Fix a crash when the destruction of a callback objecttriggers the garbage collector.
• bpo-12950: Fix passing file descriptors in multiprocessing, underOpenIndiana/Illumos.
• bpo-12764: Fix a crash in ctypes when the name of a Structure field is nota string.
• bpo-11241: subclasses of ctypes.Array can now be subclassed.
• bpo-9651: Fix a crash when ctypes.create_string_buffer(0) was passed tosome functions like file.write().
• bpo-10309: Define _GNU_SOURCE so that mremap() gets the proper signature.Without this, architectures where sizeof void* != sizeof int are broken.Patch given by Hallvard B Furuseth.
• bpo-12051: Fix segfault in json.dumps() while encoding highly-nestedobjects using the C accelerations.
• bpo-12017: Fix segfault in json.loads() while decoding highly-nestedobjects using the C accelerations.
• bpo-1838: Prevent segfault in ctypes, when _as_parameter_ on a class isset to an instance of the class.

Tests¶

• bpo-13125: Silence spurious test_lib2to3 output when in non-verbose mode.Patch by Mikhail Novikov.
• bpo-13447: Add a test file to host regression tests for bugs in thescripts found in the Tools directory.
• bpo-10881: Fix test_site failure with OS X framework builds.
• bpo-13901: Prevent test_distutils failures on OS X with –enable-shared.
• bpo-13862: Fix spurious failure in test_zlib due to runtime/compile timeminor versions not matching.
• bpo-12804: Fix test_socket and test_urllib2net failures when running testson a system without internet access.
• bpo-13726: Fix the ambiguous -S flag in regrtest. It is -o/–slow for slowtests.
• bpo-11659: Fix ResourceWarning in test_subprocess introduced by #11459.Patch by Ben Hayden.
• bpo-11577: fix ResourceWarning triggered by improved binhex test coverage
• bpo-11509: Significantly increase test coverage of fileinput. Patch byDenver Coneybeare at PyCon 2011 Sprints.
• bpo-11689: Fix a variable scoping error in an sqlite3 test
• bpo-13786: Remove unimplemented ‘trace’ long option from regrtest.py.
• bpo-13725: Fix regrtest to recognize the documented -d flag. Patch by ErnoTukia.
• bpo-13304: Skip test case if user site-packages disabled (-s orPYTHONNOUSERSITE). (Patch by Carl Meyer)
• bpo-5661: Add a test for ECONNRESET/EPIPE handling to test_asyncore. Patchby Xavier de Gaye.
• bpo-13218: Fix test_ssl failures on Debian/Ubuntu.
• Re-enable lib2to3’s test_parser.py tests, though with an expected failure(seeissue #13125).
• bpo-12656: Add tests for IPv6 and Unix sockets to test_asyncore.
• bpo-6484: Add unit tests for mailcap module (patch by Gregory Nofi)
• bpo-11651: Improve the Makefile test targets to run more of the test suitemore quickly. The –multiprocess option is now enabled by default,reducing the amount of time needed to run the tests. “make test” and “makequicktest” now include some resource-intensive tests, but no longer runthe test suite twice to check for bugs in .pyc generation.Tools/scripts/run_test.py provides an easy platform-independent way to runtest suite with sensible defaults.
• bpo-12331: The test suite for the packaging module can now run from aninstalled Python.
• bpo-12331: The test suite for lib2to3 can now run from an installedPython.
• bpo-12626: In regrtest, allow to filter tests using a glob filter with the-m (or--match) option. This works with all test cases using theunittest module. This is useful with long test suites such as test_io ortest_subprocess.
• bpo-12624: It is now possible to fail after the first failure when runningin verbose mode (-v or-W), by using the--failfast (or-G) option to regrtest. This is useful with long test suites such astest_io or test_subprocess.
• bpo-12587: Correct faulty test file and reference in test_tokenize. (Patchby Robert Xiao)
• bpo-12573: Add resource checks for dangling Thread and Process objects.
• bpo-12549: Correct test_platform to not fail when OS X returns ‘x86_64’ asthe processor type on some Mac systems.
• Skip network tests when getaddrinfo() returns EAI_AGAIN, meaning atemporary failure in name resolution.
• bpo-11812: Solve transient socket failure to connect to ‘localhost’ intest_telnetlib.py.
• Solved a potential deadlock in test_telnetlib.py. Related toissue #11812.
• Avoid failing in test_robotparser when mueblesmoraleda.com is flaky and anoverzealous DNS service (e.g. OpenDNS) redirects to a placeholder Website.
• Avoid failing in test_urllibnet.test_bad_address when some overzealous DNSservice (e.g. OpenDNS) resolves a non-existent domain name. The test isnow skipped instead.
• bpo-12440: When testing whether some bits in SSLContext.options can bereset, check the version of the OpenSSL headers Python was compiledagainst, rather than the runtime version of the OpenSSL library.
• bpo-11512: Add a test suite for the cgitb module. Patch by Robbie Clemons.
• bpo-12497: Install test/data to prevent failures of the various codecmapstests.
• bpo-12496: Install test/capath directory to prevent test_connect_capathtestcase failure in test_ssl.
• bpo-12469: Run wakeup and pending signal tests in a subprocess to run thetest in a fresh process with only one thread and to not change signalhandling of the parent process.
• bpo-8716: Avoid crashes caused by Aqua Tk on OSX when attempting to runtest_tk or test_ttk_guionly under a username that is not currently loggedin to the console windowserver (as may be the case under buildbot or ssh).
• bpo-12407: Explicitly skip test_capi.EmbeddingTest under Windows.
• bpo-12400: regrtest -W doesn’t rerun the tests twice anymore, but capturesthe output and displays it on failure instead. regrtest -v doesn’t printthe error twice anymore if there is only one error.
• bpo-12141: Install copies of template C module file so that test_build_extof test_distutils and test_command_build_ext of test_packaging are nolonger silently skipped when run outside of a build directory.
• bpo-8746: Add additional tests for os.chflags() and os.lchflags(). Patchby Garrett Cooper.
• bpo-10736: Fix test_ttk test_widgets failures with Cocoa Tk 8.5.9 2.8+ onMac OS X. (Patch by Ronald Oussoren)
• bpo-12057: Add tests for ISO 2022 codecs (iso2022_jp, iso2022_jp_2,iso2022_kr).
• bpo-12096: Fix a race condition in test_threading.test_waitfor(). Patchwritten by Charles-François Natali.
• bpo-11614: import __hello__ prints “Hello World!”. Patch written byAndreas Stührk.
• bpo-5723: Improve json tests to be executed with and withoutaccelerations.
• bpo-12041: Make test_wait3 more robust.
• bpo-11873: Change regex in test_compileall to fix occasional failures whenwhen the randomly generated temporary path happened to match the regex.
• bpo-11958: Fix FTP tests for IPv6, bind to ”::1” instead of “localhost”.Patch written by Charles-Francois Natali.
• bpo-8407: Fix tests of test_io using threads and an alarm: usepthread_sigmask() to ensure that the SIGALRM signal is received by themain thread. (See also: bpo-11859)
• bpo-11811: Factor out detection of IPv6 support on the current host andmake it available astest.support.IPV6_ENABLED. Patch byCharles-François Natali.
• bpo-10914: Add a minimal embedding test to test_capi.
• bpo-11223: Skip test_lock_acquire_interruption() andtest_rlock_acquire_interruption() of test_threadsignals if a thread lockis implemented using a POSIX mutex and a POSIX condition variable. A POSIXcondition variable cannot be interrupted by a signal (e.g. on Linux, thefutex system call is restarted).
• bpo-11790: Fix sporadic failures intest_multiprocessing.WithProcessesTestCondition.
• Fix possible “file already exists” error when running the tests inparallel.
• bpo-11719: Fix message about unexpected test_msilib skip on non-Windowsplatforms. Patch by Nadeem Vawda.
• bpo-11727: Add a –timeout option to regrtest: if a test takes more thanTIMEOUT seconds, dumps the traceback of all threads and exits.
• bpo-11653: fix -W with -j in regrtest.
• The email test suite now lives in the Lib/test/test_email package. Thetest harness code has also been modernized to allow use of new unittestfeatures.
• regrtest now discovers test packages as well as test modules.
• bpo-11577: improve test coverage of binhex.py. Patch by Arkady Koplyarov.
• New test_crashers added to exercise the scripts in the Lib/test/crashersdirectory and confirm they fail as expected
• bpo-11578: added test for the timeit module. Patch by Michael Henry.
• bpo-11503: improve test coverage of posixpath.py. Patch by Evan Dandrea.
• bpo-11505: improves test coverage of string.py, increases granularity ofstring.Formatter tests. Initial patch by Alicia Arlen.
• bpo-11548: Improve test coverage of the shutil module. Patch by EvanDandrea.
• bpo-11554: Reactivated test_email_codecs.
• bpo-11505: improves test coverage of string.py. Patch by Alicia Arlen
• bpo-11490: test_subprocess.test_leaking_fds_on_error no longer gives afalse positive if the last directory in the path is inaccessible.
• bpo-11223: Fix test_threadsignals to fail, not hang, when thenon-semaphore implementation of locks is used under POSIX.
• bpo-10911: Add tests on CGI with non-ASCII characters. Patch written byPierre Quentel.
• bpo-9931: Fix hangs in GUI tests under Windows in certain conditions.Patch by Hirokazu Yamamoto.
• bpo-10512: Properly close sockets under test.test_cgi.
• bpo-10992: Make tests pass under coverage.
• bpo-10826: Prevent sporadic failure in test_subprocess on Solaris due toopen door files.
• bpo-10990: Prevent tests from clobbering a set trace function.

C API¶

• bpo-13452: PyUnicode_EncodeDecimal() doesn’t support error handlersdifferent than “strict” anymore. The caller was unable to compute the sizeof the output buffer: it depends on the error handler.
• bpo-13560: Add PyUnicode_DecodeLocale(), PyUnicode_DecodeLocaleAndSize()and PyUnicode_EncodeLocale() functions to the C API to decode/encodefrom/to the current locale encoding.
• bpo-10831: PyUnicode_FromFormat() supports %li, %lli and %zi formats.
• bpo-11246: Fix PyUnicode_FromFormat(“%V”) to decode the byte string fromUTF-8 (with replace error handler) instead of ISO-8859-1 (in strict mode).Patch written by Ray Allen.
• bpo-10830: Fix PyUnicode_FromFormatV(“%c”) for non-BMP characters onnarrow build.
• Add PyObject_GenericGetDict and PyObject_GeneriSetDict. They are genericimplementations for the getter and setter of a__dict__ descriptor ofC types.
• bpo-13727: Add 3 macros to access PyDateTime_Delta members:PyDateTime_DELTA_GET_DAYS, PyDateTime_DELTA_GET_SECONDS,PyDateTime_DELTA_GET_MICROSECONDS.
• bpo-10542: Add 4 macros to work with surrogates: Py_UNICODE_IS_SURROGATE,Py_UNICODE_IS_HIGH_SURROGATE, Py_UNICODE_IS_LOW_SURROGATE,Py_UNICODE_JOIN_SURROGATES.
• bpo-12724: Add Py_RETURN_NOTIMPLEMENTED macro for returningNotImplemented.
• PY_PATCHLEVEL_REVISION has been removed, since it’s meaningless withMercurial.
• bpo-12173: The first argument of PyImport_ImportModuleLevel is nowconstchar* instead ofchar*.
• bpo-12380: PyArg_ParseTuple now accepts a bytearray for the ‘c’ format.

Documentation¶

• bpo-23006: Improve the documentation and indexing of dict.__missing__. Addan entry in the language datamodel special methods section. Revise andindex its discussion in the stdtypes mapping/dict section.
• bpo-13989: Document that GzipFile does not support text mode, and give amore helpful error message when opened with an invalid mode string.
• bpo-13921: Undocument and clean up sqlite3.OptimizedUnicode, which isobsolete in Python 3.x. It’s now aliased to str for backwardscompatibility.
• bpo-12102: Document that buffered files must be flushed before being usedwith mmap. Patch by Steffen Daode Nurpmeso.
• bpo-8982: Improve the documentation for the argparse Namespace object.
• bpo-9343: Document that argparse parent parsers must be configured beforetheir children.
• bpo-13498: Clarify docs of os.makedirs()’s exist_ok argument. Done withgreat native- speaker help from R. David Murray.
• bpo-13491: Fix many errors in sqlite3 documentation. Initial patch for#13491 by Johannes Vogel. (See also: bpo-13995)
• bpo-13402: Document absoluteness of sys.executable.
• bpo-13883: PYTHONCASEOK also works on OS X.
• bpo-9021: Add an introduction to the copy module documentation.
• bpo-6005: Examples in the socket library documentation use sendall, whererelevant, instead send method.
• bpo-12798: Updated the mimetypes documentation.
• bpo-12949: Document the kwonlyargcount argument for the PyCode_New C APIfunction.
• bpo-13513: Fix io.IOBase documentation to correctly link to theio.IOBase.readline method instead of the readline module.
• bpo-13237: Reorganise subprocess documentation to emphasise conveniencefunctions and the most commonly needed arguments to Popen.
• bpo-13141: Demonstrate recommended style for socketserver examples.
• bpo-11818: Fix tempfile examples for Python 3.

(For information about older versions, consult the HISTORY file.)