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Python News

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(editors: check NEWS.help for information about editing NEWS using ReST.)

What's New in Python 3.0.1?

===========================

*Release date: 13-Feb-2009*

Core and Builtins

-----------------

- Issue #5137: Make len() correctly raise a TypeError when a __len__ method

returns a non-number type.

- Issue #5182: Removed memoryview.__str__.

- Issue #1717: Removed builtin cmp() function, dropped tp_compare

slot, the C API functions PyObject_Compare and PyUnicode_Compare and

the type definition cmpfunc. The tp_compare slot has been renamed

to tp_reserved, and is reserved for future usage.

- Issue 1242657: the __len__() and __length_hint__() calls in several tools

were suppressing all exceptions. These include list() and bytearray().

- Issue #4707: round(x, n) now returns an integer if x is an integer.

Previously it returned a float.

- Issue #4874: Most builtin decoders now reject unicode input.

- Issue #4842: Don't allow trailing 'L' when constructing an integer

from a string.

- Issue #4991: os.fdopen now raises an OSError for invalid file descriptors.

- Issue #4838: When a module is deallocated, free the memory backing the

optional module state data.

- Issue #4910: Rename nb_long slot to nb_reserved, and change its

type to (void *).

- Issue #4935: The overflow checking code in the expandtabs() method common

to str, bytes and bytearray could be optimized away by the compiler, letting

the interpreter segfault instead of raising an error.

- Issue #4910: Builtin int() function and PyNumber_Long/PyNumber_Int API

function no longer attempt to call the __long__ slot to convert an object

to an integer. Only the __int__ and __trunc__ slots are examined.

- Issue #4604: Some objects of the I/O library could still be used after

having been closed (for instance, a read() call could return some

previously buffered data). Patch by Dmitry Vasiliev.

- Issue #4705: Fix the -u ("unbuffered binary stdout and stderr") command-line

flag to work properly. Furthermore, when specifying -u, the text stdout

and stderr streams have line-by-line buffering enabled (the default being

to buffer arbitrary chunks of data).

- Issue #1180193: When importing a module from a .pyc (or .pyo) file with

an existing .py counterpart, override the co_filename attributes of all

code objects if the original filename is obsolete (which can happen if the

file has been renamed, moved, or if it is accessed through different paths).

Patch by Ziga Seilnacht and Jean-Paul Calderone.

- Issue #4580: Fix slicing of memoryviews when the item size is greater than

one byte. Also fixes the meaning of len() so that it returns the number of

items, rather than the size in bytes.

- Issue #2467: gc.DEBUG_STATS reported invalid elapsed times. Also, always

print elapsed times, not only when some objects are uncollectable /

unreachable. Original patch by Neil Schemenauer.

- Issue #4075: Use OutputDebugStringW in Py_FatalError.

- Issue #4747: When the terminal does not use utf-8, executing a script with

non-ascii characters in its name could fail with a "SyntaxError: None" error.

- Issue #4797: IOError.filename was not set when _fileio.FileIO failed to open

file with `bytes' filename on Windows.

- Issue #3680: Reference cycles created through a dict, set or deque iterator

did not get collected.

- Issue #4701: PyObject_Hash now implicitly calls PyType_Ready on types

where the tp_hash and tp_dict slots are both NULL.

- Issue #4759: fix a segfault for bytearray.translate(x, None).

- Added test case to ensure attempts to read from a file opened for writing

fail.

- Issue #3106: Speedup some comparisons (str/str and int/int).

- Issue #2173: When getting device encoding, check that return value of

nl_langinfo is not the empty string. This was causing silent build

failures on OS X.

- Issue #4597: Fixed several opcodes that weren't always propagating

exceptions.

- Issue #4589: Fixed exception handling when the __exit__ function of a

context manager returns a value that cannot be converted to a bool.

- Issue #4533: File read operation was dreadfully slow due to a slowly

growing read buffer. Fixed by using the same growth rate algorithm as

Python 2.x.

- Issue #4509: Various issues surrounding resize of bytearray objects to

which there are buffer exports (e.g. memoryview instances).

- Issue #4569: Interpreter crash when mutating a memoryview with an item size

larger than 1.

Library

-------

- Issue #4998: The memory saving effect of __slots__ had been lost on Fractions

which inherited from numbers.py which did not have __slots__ defined. The

numbers hierarchy now has its own __slots__ declarations.

- Issue #4631: Fix urlopen() result when an HTTP response uses chunked

encoding.

- Issue #5203: Fixed ctypes segfaults when passing a unicode string to a

function without argtypes (only occurs if HAVE_USABLE_WCHAR_T is false).

- Issue #3386: distutils.sysconfig.get_python_lib prefix argument was ignored

under NT and OS2. Patch by Philip Jenvey.

- Issue #3321: _multiprocessing.Connection() doesn't check handle; added checks

for *nix machines for negative handles and large int handles. Without this check

it is possible to segfault the interpreter.

- Issue #4449: AssertionError in mp_benchmarks.py, caused by an underlying issue

in sharedctypes.py.

- Issue #4890: Handle empty text search pattern in Tkinter.Text.search.

- Partial fix to issue #1731706: memory leak in Tkapp_Call when calling

from a thread different than the one that created the Tcl interpreter.

Patch by Robert Hancock.

- Issue #5132: Fixed trouble building extensions under Solaris with

--enabled-shared activated. Initial patch by Dave Peterson.

- Issue #1581476: Always use the Tcl global namespace when calling into Tcl.

- The shelve module now defaults to pickle protocol 3.

- Issue #2047: shutil.move() could believe that its destination path was

inside its source path if it began with the same letters (e.g. "src" vs.

"src.new").

- Removed isSequenceType(), isMappingType, and isNumberType() from the

operator module; use the abstract base classes instead. Also removed

the repeat() function; use mul() instead.

- Issue 5021: doctest.testfile() did not create __name__ and

collections.namedtuple() relied on __name__ being defined.

- Issue #1885: distutils. When running sdist with --formats=tar,gztar

the tar file was overriden by the gztar one.

- Issue #1672332: fix unpickling of subnormal floats, which was

producing a ValueError on some platforms.

- Issue #3881: Help Tcl to load even when started through the

unreadable local symlink to "Program Files" on Vista.

- Issue #4710: Extract directories properly in the zipfile module;

allow adding directories to a zipfile.

- Issue #5008: When a file is opened in append mode with the new IO library,

do an explicit seek to the end of file (so that e.g. tell() returns the

file size rather than 0). This is consistent with the behaviour of the

traditional 2.x file object.

- Issue #5013: Fixed a bug in FileHandler which occurred when the delay

parameter was set.

- Issue #4842: Always append a trailing 'L' when pickling longs using

pickle protocol 0. When reading, the 'L' is optional.

- Issue #3826 and #4791: The socket module now closes the underlying socket

appropriately when it is being used via socket.makefile() objects

rather than delaying the close by waiting for garbage collection to do it.

- Issue #4998: Decimal no longer subclasses from or is registered to

numbers.Real. Instead, it is registered to numbers.Number so that

isinstance(d, Number) will work.

- Issue #4867: Fixed a crash in ctypes when passing a string to a

function without defining argtypes.

- Restore Python 2.3 compatibility for decimal.py.

- Issue #3638: Remove functions from _tkinter module level that depend on

TkappObject to work with multiple threads.

- Issue #4718: Adapt the wsgiref package so that it actually works with

Python 3.x, in accordance with the `official amendments of the spec

<http://www.wsgi.org/wsgi/Amendments_1.0>`_.

- Fractions.from_float() no longer loses precision for integers too big to

cast as floats.

- Issue #4812: add missing underscore prefix to some internal-use-only

constants in the decimal module. (Dec_0 becomes _Dec_0, etc.)

- Issue 4790: The nsmallest() and nlargest() functions in the heapq module

did unnecessary work in the common case where no key function was specified.

- Issue #4795: inspect.isgeneratorfunction() returns False instead of None when

the function is not a generator.

- Issue #4702: Throwing a DistutilsPlatformError instead of IOError in case

no MSVC compiler is found under Windows. Original patch by Philip Jenvey.

- Issue #4646: distutils was choking on empty options arg in the setup

function. Original patch by Thomas Heller.

- Issue #3767: Convert Tk object to string in tkColorChooser.

- Issue #3248: Allow placing ScrolledText in a PanedWindow.

- Issue #4739: Add pydoc help topics for symbols, so that e.g. help('@')

works as expected in the interactive environment.

- Issue #4574: reading an UTF16-encoded text file crashes if \r on 64-char

boundary.

- Issue #4223: inspect.getsource() will now correctly display source code

for packages loaded via zipimport (or any other conformant PEP 302

loader). Original patch by Alexander Belopolsky.

- Issue #4201: pdb can now access and display source code loaded via

zipimport (or any other conformant PEP 302 loader). Original patch by

Alexander Belopolsky.

- Issue #4197: doctests in modules loaded via zipimport (or any other PEP

302 conformant loader) will now work correctly in most cases (they

are still subject to the constraints that exist for all code running

from inside a module loaded via a PEP 302 loader and attempting to

perform IO operations based on __file__). Original patch by

Alexander Belopolsky.

- Issues #4082 and #4512: Add runpy support to zipimport in a manner that

allows backporting to maintenance branches. Original patch by

Alexander Belopolsky.

- Issue #4616: TarFile.utime(): Restore directory times on Windows.

- Issue #4021: tokenize.detect_encoding() now raises a SyntaxError when the

codec cannot be found. This is for compatibility with the builtin behavior.

- Issue #4084: Fix max, min, max_mag and min_mag Decimal methods to

give correct results in the case where one argument is a quiet NaN

and the other is a finite number that requires rounding.

- Issue #4483: _dbm module now builds on systems with gdbm & gdbm_compat

libs.

- Issue #4529: fix the parser module's validation of try-except-finally

statements.

- Issue #4458: getopt.gnu_getopt() now recognizes a single "-" as an argument,

not a malformed option.

- Added the subprocess.check_output() convenience function to get output

from a subprocess on success or raise an exception on error.

- Issue #4542: On Windows, binascii.crc32 still accepted str as binary input;

the corresponding tests now pass.

- Issue #4537: webbrowser.UnixBrowser would fail to open the browser because

it was calling the wrong open() function.

- Issue #1055234: cgi.parse_header(): Fixed parsing of header parameters to

support unusual filenames (such as those containing semi-colons) in

Content-Disposition headers.

- Issue #4861: ctypes.util.find_library(): Robustify. Fix library detection on

biarch systems. Try to rely on ldconfig only, without using objdump and gcc.

- Issue #5104: The socket module now raises OverflowError when 16-bit port and

protocol numbers are supplied outside the allowed 0-65536 range on bind()

and getservbyport().

Tools/Demos

-----------

- Issue #4704: remove use of cmp() in pybench, bump its version number to 2.1,

and make it 2.6-compatible.

- Issue #4677: add two list comprehension tests to pybench.

Build

-----

- Issue #5134: Silence compiler warnings when compiling sqlite with VC++.

- Issue #4494: Fix build with Py_NO_ENABLE_SHARED on Windows.

- Issue #4472: "configure --enable-shared" now works on OSX

- Issues #4728 and #4060: WORDS_BIGEDIAN is now correct in Universal builds.

- Issue #4389: Add icon to the uninstall entry in "add-and-remove-programs".

- Issue #4289: Remove Cancel button from AdvancedDlg.

- Issue #1656675: Register a drop handler for .py* files on Windows.

- Issue #4120: Exclude manifest from extension modules in VS2008.

- Issue #4091: Install pythonxy.dll in system32 again.

- Issue #4018: Disable "for me" installations on Vista.

- Issue #3758: Add ``patchcheck`` build target to .PHONY.

- Issue #4204: Fixed module build errors on FreeBSD 4.

C-API

-----

- Issue #4720: The format for PyArg_ParseTupleAndKeywords can begin with '|'.

- Issue #3632: from the gdb debugger, the 'pyo' macro can now be called when

the GIL is released, or owned by another thread.

- Issue #4122: On Windows, fix a compilation error when using the

Py_UNICODE_ISSPACE macro in an extension module.

Extension Modules

-----------------

- Issue #3745: Fix hashlib to always reject unicode and non buffer-api

supporting objects as input no matter how it was compiled (built in

implementations or external openssl library).

- Issue #4397: Fix occasional test_socket failure on OS X.

- Issue #4279: Fix build of parsermodule under Cygwin.

- Issue #4228: Pack negative values the same way as 2.4 in struct's L format.

- Issue #1040026: Fix os.times result on systems where HZ is incorrect.

- Issues #3167, #3682: Fix test_math failures for log, log10 on Solaris,

OpenBSD.

- Issue #4583: array.array would not always prohibit resizing when a buffer

has been exported, resulting in an interpreter crash when accessing the

buffer.

What's New in Python 3.0 final

==============================

*Release date: 03-Dec-2008*

Core and Builtins

-----------------

- Issue #3996: On Windows, the PyOS_CheckStack function would cause the

interpreter to abort ("Fatal Python error: Could not reset the stack!")

instead of throwing a MemoryError.

- Issue #3689: The list reversed iterator now supports __length_hint__

instead of __len__. Behavior now matches other reversed iterators.

- Issue #4367: Python would segfault during compiling when the unicodedata

module couldn't be imported and \N escapes were present.

- Fix build failure of _cursesmodule.c building with -D_FORTIFY_SOURCE=2.

Library

-------

- Issue #4387: binascii now refuses to accept str as binary input.

- Issue #4073: Add 2to3 support to build_scripts, refactor that support

in build_py.

- IDLE would print a "Unhandled server exception!" message when internal

debugging is enabled.

- Issue #4455: IDLE failed to display the windows list when two windows have

the same title.

- Issue #3741: DISTUTILS_USE_SDK set causes msvc9compiler.py to raise an

exception.

- Issue #4433: Fixed an access violation when garbage collecting

_ctypes.COMError instances.

- Issue #4429: Fixed UnicodeDecodeError in ctypes.

- Issue #4373: Corrected a potential reference leak in the pickle module and

silenced a false positive ref leak in distutils.tests.test_build_ext.

- Issue #4382: dbm.dumb did not specify the expected file encoding for opened

files.

- Issue #4383: When IDLE cannot make the connection to its subprocess, it would

fail to properly display the error message.

Build

-----

- Issue #4407: Fix source file that caused the compileall step in Windows

installer to fail.

Docs

----

- Issue #4449: Fixed multiprocessing examples

- Issue #3799: Document that dbm.gnu and dbm.ndbm will accept string arguments

for keys and values which will be converted to bytes before committal.

What's New in Python 3.0 release candidate 3?

=============================================

*Release date: 20-Nov-2008*

Core and Builtins

-----------------

- Issue #4349: sys.path included a non-existent platform directory because of a

faulty Makefile.

- Issue #3327: Don't overallocate in the modules_by_index list.

- Issue #1721812: Binary set operations and copy() returned the input type

instead of the appropriate base type. This was incorrect because set

subclasses would be created without their __init__() method being called.

The corrected behavior brings sets into line with lists and dicts.

- Issue #4296: Fix PyObject_RichCompareBool so that "x in [x]" evaluates to

True, even when x doesn't compare equal to itself. This was a regression

from 2.6.

- Issue #3705: Command-line arguments were not correctly decoded when the

terminal does not use UTF8.

Library

-------

- Issue #4363: The uuid.uuid1() and uuid.uuid4() functions now work even if

the ctypes module is not present.

- FileIO's mode attribute now always includes ``"b"``.

- Issue #3799: Fix dbm.dumb to accept strings as well as bytes for keys. String

keys are now written out in UTF-8.

- Issue #4338: Fix distutils upload command.

- Issue #4354: Fix distutils register command.

- Issue #4116: Resolve member name conflict in ScrolledCanvas.__init__.

- Issue #4307: The named tuple that ``inspect.getfullargspec()`` returns now

uses ``kwonlydefaults`` instead of ``kwdefaults``.

- Issue #4298: Fix a segfault when pickle.loads is passed a ill-formed input.

- Issue #4283: Fix a left-over "iteritems" call in distutils.

Build

-----

- Issue #4389: Add icon to the uninstall entry in "add-and-remove-programs".

- Issue #4289: Remove Cancel button from AdvancedDlg.

- Issue #1656675: Register a drop handler for .py* files on Windows.

Tools/Demos

-----------

- Demos of the socketserver module now work with Python 3.

What's New in Python 3.0 release candidate 2

============================================

*Release date: 05-Nov-2008*

Core and Builtins

-----------------

- Issue #4211: The __path__ attribute of frozen packages is now a list instead

of a string as required by PEP 302.

- Issue #3727: Fixed poplib.

- Issue #3714: Fixed nntplib by using bytes where appropriate.

- Issue #1210: Fixed imaplib and its documentation.

- Issue #4233: Changed semantic of ``_fileio.FileIO``'s ``close()``

method on file objects with closefd=False. The file descriptor is still

kept open but the file object behaves like a closed file. The ``FileIO``

object also got a new readonly attribute ``closefd``.

- Issue #3626: On cygwin, starting python with a non-existent script name

would not display anything if the file name is only 1 character long.

- Issue #4176: Fixed a crash when pickling an object which ``__reduce__``

method does not return iterators for the 4th and 5th items.

- Issue #3723: Fixed initialization of subinterpreters.

- Issue #4213: The file system encoding is now normalized by the

codec subsystem, for example UTF-8 is turned into utf-8.

- Issue #4200: Changed the atexit module to store its state in its

PyModuleDef atexitmodule. This fixes a bug with multiple subinterpeters.

- Issue #4237: io.FileIO() was raising invalid warnings caused by

insufficient initialization of PyFileIOObject struct members.

- Issue #4170: Pickling a collections.defaultdict object would crash the

interpreter.

- Issue #4146: Compilation on OpenBSD has been restored.

- Issue #3574: compile() incorrectly handled source code encoded as Latin-1.

- Issues #2384 and #3975: Tracebacks were not correctly printed when the

source file contains a ``coding:`` header: the wrong line was displayed, and

the encoding was not respected.

- Issue #3740: Null-initialize module state.

- Issue #3946: PyObject_CheckReadBuffer crashed on a memoryview object.

- Issue #1688: On Windows, the input() prompt was not correctly displayed if it

contains non-ascii characters.

- Bug #3951: Py_USING_MEMORY_DEBUGGER should not be enabled by default.

Library

-------

- Issue #3664: The pickle module could segfault if a subclass of Pickler fails

to call the base __init__ method.

- Issue #3725: telnetlib now works completely in bytes.

- Issue #4072: Restore build_py_2to3.

- Issue #4014: Don't claim that Python has an Alpha release status, in addition

to claiming it is Mature.

- Issue #3187: Add sys.setfilesystemencoding.

- Issue #3187: Better support for "undecodable" filenames. Code by Victor

Stinner, with small tweaks by GvR.

- Issue #3965: Allow repeated calls to turtle.Screen, by making it a

true singleton object.

- Issue #3911: ftplib.FTP.makeport() could give invalid port numbers.

- Issue #3929: When the database cannot be opened, dbm.open() would incorrectly

raise a TypeError: "'tuple' object is not callable" instead of the expected

dbm.error.

- Bug #3884: Make the turtle module toplevel again.

- Issue #3547: Fixed ctypes structures bitfields of varying integer

sizes.

Extension Modules

-----------------

- Issue #3659: Subclasses of str didn't work as SQL parameters.

Build

-----

- Issue #4120: Exclude manifest from extension modules in VS2008.

- Issue #4091: Install pythonxy.dll in system32 again.

- Issue #4018: Disable "for me" installations on Vista.

- Issue #4204: Fixed module build errors on FreeBSD 4.

Tools/Demos

-----------

- Issue #3717: Fix Demo/embed/demo.c.

- Issue #4072: Add a distutils demo for build_py_2to3.

What's New in Python 3.0 release candidate 1

============================================

*Release date: 17-Sep-2008*

Core and Builtins

-----------------

- Issue #3827: memoryview lost its size attribute in favor of using len(view).

- Issue #3813: could not lanch python.exe via symbolic link on cygwin.

- Issue #3705: fix crash when given a non-ascii value on the command line for

the "-c" and "-m" parameters. Now the behaviour is as expected under Linux,

although under Windows it fails at a later point.

- Issue #3279: Importing site at interpreter was failing silently because the

site module uses the open builtin which was not initialized at the time.

- Issue #3660: Corrected a reference leak in str.encode() when the encoder

does not return a bytes object.

- Issue #3774: Added a few more checks in PyTokenizer_FindEncoding to handle

error conditions.

- Issue #3594: Fix Parser/tokenizer.c:fp_setreadl() to open the file being

tokenized by either a file path or file pointer for the benefit of

PyTokenizer_FindEncoding().

- Issue #3696: Error parsing arguments on OpenBSD <= 4.4 and Cygwin. On

these systems, the mbstowcs() function is slightly buggy and must be

replaced with strlen() for the purpose of counting of number of wide

characters needed to represent the multi-byte character string.

- Issue #3697: "Fatal Python error: Cannot recover from stack overflow"

could be easily encountered under Windows in debug mode when exercising

the recursion limit checking code, due to bogus handling of recursion

limit when USE_STACKCHEK was enabled.

- Issue 3639: The _warnings module could segfault the interpreter when

unexpected types were passed in as arguments.

- Issue #3712: The memoryview object had a reference leak and didn't support

cyclic garbage collection.

- Issue #3668: Fix a memory leak with the "s*" argument parser in

PyArg_ParseTuple and friends, which occurred when the argument for "s*"

was correctly parsed but parsing of subsequent arguments failed.

- Issue #3611: An exception __context__ could be cleared in a complex pattern

involving a __del__ method re-raising an exception.

- Issue #2534: speed up isinstance() and issubclass() by 50-70%, so as to

match Python 2.5 speed despite the __instancecheck__ / __subclasscheck__

mechanism. In the process, fix a bug where isinstance() and issubclass(),

when given a tuple of classes as second argument, were looking up

__instancecheck__ / __subclasscheck__ on the tuple rather than on each

type object.

- Issue #3663: Py_None was decref'd when printing SyntaxErrors.

- Issue #3651: Fix various memory leaks when using the buffer

interface, or when the "s#" code of PyArg_ParseTuple is given a

bytes object.

- Issue #3657: Fix uninitialized memory read when pickling longs.

Found by valgrind.

- Apply security patches from Apple.

- Fix crashes on memory allocation failure found with failmalloc.

- Fix memory leaks found with valgrind and update suppressions file.

- Fix compiler warnings in opt mode which would lead to invalid memory reads.

- Fix problem using wrong name in decimal module reported by pychecker.

- Issue #3650: Fixed a reference leak in bytes.split('x').

- bytes(o) now tries to use o.__bytes__() before using fallbacks.

- Issue #1204: The configure script now tests for additional libraries

that may be required when linking against readline. This fixes issues

with x86_64 builds on some platforms (a few Linux flavors and OpenBSD).

C API

-----

- PyObject_Bytes and PyBytes_FromObject were added.

Library

-------

- Issue #3756: make re.escape() handle bytes as well as str.

- Issue #3800: fix filter() related bug in formatter.py.

- Issue #874900: fix behaviour of threading module after a fork.

- Issue #3535: zipfile couldn't read some zip files larger than 2GB.

- Issue #3776: Deprecate the bsddb package for removal in 3.0.

- Issue #3762: platform.architecture() fails if python is lanched via

its symbolic link.

- Issue #3660: fix a memory leak in the C accelerator of the pickle module.

- Issue #3160: the "bdist_wininst" distutils command didn't work.

- Issue #1658: tkinter changes dict size during iteration in both

tkinter.BaseWidget and tkinter.scrolledtext.ScrolledText.

- The bsddb module (and therefore the dbm.bsd module) has been removed.

It is now maintained outside of the standard library at

http://www.jcea.es/programacion/pybsddb.htm.

- Issue 600362: Relocated parse_qs() and parse_qsl(), from the cgi module

to the urlparse one. Added a DeprecationWarning in the old module, it

will be deprecated in the future.

- Issue #3719: platform.architecture() fails if there are spaces in the

path to the Python binary.

- Issue 3602: As part of the merge of r66135, make the parameters on

warnings.catch_warnings() keyword-only. Also remove a DeprecationWarning.

- The deprecation warnings for the camelCase threading API names were removed.

- Issue #3110: multiprocessing fails to compiel on solaris 10 due to missing

SEM_VALUE_MAX.

Extension Modules

-----------------

- Issue #3782: os.write() must not accept unicode strings.

- Issue #2975: When compiling several extension modules with Visual Studio 2008

from the same python interpreter, some environment variables would grow

without limit.

- Issue #3643: Added a few more checks to _testcapi to prevent segfaults by

exploitation of poor argument checking.

- bsddb code updated to version 4.7.3pre2. This code is the same than

Python 2.6 one, since the intention is to keep an unified 2.x/3.x codebase.

The Python code is automatically translated using "2to3". Please, do not

update this code in Python 3.0 by hand. Update the 2.6 one and then

do "2to3".

- The _bytesio and _stringio modules are now compiled into the python binary.

- Issue #3492 and #3790: Fixed the zlib module and zipimport module uses of

mutable bytearray objects where they should have been using immutable bytes.

- Issue #3797: Fixed the dbm, marshal, mmap, ossaudiodev, & winreg modules to

return bytes objects instead of bytearray objects.

Tools/Demos

-----------

- Fix Misc/gdbinit so it works.

Build

-----

- Issue #3812: Failed to build python if configure --without-threads.

- Issue #3791: Remove the bsddb module from the Windows installer, and the

core bsddb library from the Windows build files.

What's new in Python 3.0b3?

===========================

*Release date: 20-Aug-2008*

Core and Builtins

-----------------

- Issue #3653: Fix a segfault when sys.excepthook was called with invalid

arguments.

- Issue #2394: implement more of the memoryview API, with the caveat that

only one-dimensional contiguous buffers are supported and exercised right

now. Slicing, slice assignment and comparison (equality and inequality)

have been added. Also, the tolist() method has been implemented, but only

for byte buffers. Endly, the API has been updated to return bytes objects

wherever it used to return bytearrays.

- Issue #3560: clean up the new C PyMemoryView API so that naming is

internally consistent; add macros PyMemoryView_GET_BASE() and

PyMemoryView_GET_BUFFER() to access useful properties of a memory views

without relying on a particular implementation; remove the ill-named

PyMemoryView() function (PyMemoryView_GET_BUFFER() can be used instead).

- ctypes function pointers that are COM methods have a boolean True

value again.

- Issue #1819: function calls with several named parameters are now on

average 35% faster (as measured by pybench).

- The undocumented C APIs PyUnicode_AsString() and

PyUnicode_AsStringAndSize() were made private to the interpreter, in

order to be able to refine their interfaces for Python 3.1.

If you need to access the UTF-8 representation of a Unicode object

as bytes string, please use PyUnicode_AsUTF8String() instead.

- Issue #3460: PyUnicode_Join() implementation is 10% to 80% faster thanks

to Python 3.0's stricter semantics which allow to avoid successive

reallocations of the result string (this also affects str.join()).

Library

-------

- Issue #1276: Added temporary aliases for CJK Mac encodings to resolve

a build problem on MacOS with CJK locales. It adds four temporary

mappings to existing legacy codecs that are virtually compatible

with Mac encodings. They will be replaced by codecs correctly

implemented in 3.1.

- Issue #3614: Corrected a typo in xmlrpc.client, leading to a NameError

"global name 'header' is not defined".

- Issue #2834: update the regular expression library to match the unicode

standards of py3k. In other words, mixing bytes and unicode strings

(be it as pattern, search string or replacement string) raises a TypeError.

Moreover, the re.UNICODE flag is enabled automatically for unicode patterns,

and can be disabled by specifying a new re.ASCII flag; as for bytes

patterns, ASCII matching is the only option and trying to specify re.UNICODE

for such patterns raises a ValueError.

- Issue #3300: make urllib.parse.[un]quote() default to UTF-8.

Code contributed by Matt Giuca. quote() now encodes the input

before quoting, unquote() decodes after unquoting. There are

new arguments to change the encoding and errors settings.

There are also new APIs to skip the encode/decode steps.

[un]quote_plus() are also affected.

- Issue #2235: numbers.Number now blocks inheritance of the default id()

based hash because that hash mechanism is not correct for numeric types.

All concrete numeric types that inherit from Number (rather than just

registering with it) must explicitly provide a hash implementation in

order for their instances to be hashable.

- Issue #2676: in the email package, content-type parsing was hanging on

pathological input because of quadratic or exponential behaviour of a

regular expression.

- Issue #3476: binary buffered reading through the new "io" library is now

thread-safe.

- Issue #1342811: Fix leak in Tkinter.Menu.delete. Commands associated to

menu entries were not deleted.

- Remove the TarFileCompat class from tarfile.py.

- Issue #2491: os.fdopen is now almost an alias for the built-in open(), and

accepts the same parameters. It just checks that its first argument is an

integer.

- Issue #3394: zipfile.writestr sets external attributes when passed a

file name rather than a ZipInfo instance, so files are extracted with

mode 0600 rather than 000 under Unix.

- Issue #2523: Fix quadratic behaviour when read()ing a binary file without

asking for a specific length.

Extension Modules

-----------------

- Bug #3542: Support Unicode strings in _msi module.

What's new in Python 3.0b2?

===========================

*Release date: 17-Jul-2008*

Core and Builtins

-----------------

- Issue #3008: the float type has a new instance method 'float.hex'

and a new class method 'float.fromhex' to convert floating-point

numbers to and from hexadecimal strings, respectively.

- Issue #3083: Add alternate (#) formatting for bin, oct, hex output

for str.format(). This adds the prefix 0b, 0o, or 0x, respectively.

- Issue #3280: like chr(), the "%c" format now accepts unicode code points

beyond the Basic Multilingual Plane (above 0xffff) on all configurations. On

"narrow Unicode" builds, the result is a string of 2 code units, forming a

UTF-16 surrogate pair.

- Issue #3282: str.isprintable() should return False for undefined

Unicode characters.

- Issue #3236: Return small longs from PyLong_FromString.

- Exception tracebacks now support exception chaining.

Library

-------

- Removed the sunaudio module. Use sunau instead.

- Issue #3554: ctypes.string_at and ctypes.wstring_at did call Python

api functions without holding the GIL, which could lead to a fatal

error when they failed.

- Issue #799428: Fix Tkinter.Misc._nametowidget to unwrap Tcl command objects.

- Removed "ast" function aliases from the parser module.

- Issue #3313: Fixed a crash when a failed dlopen() call does not set

a valid dlerror() message.

- Issue #3258: Fixed a crash when a ctypes POINTER type to an

incomplete structure was created.

- Issue #2683: Fix inconsistency in subprocess.Popen.communicate(): the

argument now must be a bytes object in any case.

- Issue #3145: help("modules whatever") failed when trying to load the source

code of every single module of the standard library, including invalid files

used in the test suite.

- The gettext library now consistently uses Unicode strings for message ids

and message strings, and ``ugettext()`` and the like don't exist anymore.

- The traceback module has been expanded to handle chained exceptions.

C API

-----

- Issue #3247: the function Py_FindMethod was removed. Modern types should

use the tp_methods slot instead.

Tools/Demos

-----------

- The Mac/Demos directory has been removed.

- All of the Mac scripts have been removed (including BuildApplet.py).

What's new in Python 3.0b1?

===========================

*Release date: 18-Jun-2008*

Core and Builtins

-----------------

- Issue #3211: warnings.warn_explicit() did not guard against its 'registry'

argument being anything other than a dict or None. Also fixed a bug in error

handling when 'message' and 'category' were both set to None, triggering a

bus error.

- Issue #3100: Corrected a crash on deallocation of a subclassed weakref which

holds the last (strong) reference to its referent.

- Issue #2630: implement PEP 3138. repr() now returns printable

Unicode characters unescaped, to get an ASCII-only representation

of an object use ascii().

- Issue #1342: On windows, Python could not start when installed in a

directory with non-ascii characters.

- Implement PEP 3121: new module initialization and finalization API.

- Removed the already-defunct ``-t`` option.

- Issue #2957: Corrected a ValueError "recursion limit exceeded", when

unmarshalling many code objects, which happens when importing a

large .pyc file (~1000 functions).

- Issue #2963: fix merging oversight that disabled method cache for

all types.

- Issue #2964: fix a missing INCREF in instancemethod_descr_get.

- Issue #2895: Don't crash when given bytes objects as keyword names.

- Issue #2798: When parsing arguments with PyArg_ParseTuple, the "s"

code now allows any unicode string and returns a utf-8 encoded

buffer, just like the "s#" code already does. The "z" code was

corrected as well.