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Python News

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What's New in Python 2.6.2

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

*Release date: 14-Apr-2009*

What's New in Python 2.6.2 rc 1

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

*Release date: 06-Apr-2009*

Core and Builtins

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

- xrange() is now registered as a Sequence.

- Fix a problem in PyErr_NormalizeException that leads to "undetected errors"

when hitting the recursion limit under certain circumstances.

- Issue #1665206: Remove the last eager import in _warnings.c and make it lazy.

- Issue #4034: Fix weird attribute error messages of the traceback object. (As

a result traceback.__members__ no longer exists.)

- Issue #5247: Improve error message when unknown format codes are

used when using str.format() with str, unicode, long, int, and

float arguments.

- Running Python with the -3 option now also warns about classic division

for ints and longs.

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

parameter was set.

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

were suppressing all exceptions. These include list(), filter(), map(),

zip(), and bytearray().

- 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 #4915: Port sysmodule to Windows CE.

- 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code objects if the original filename is obsolete (which can happen if the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 #4075: Use OutputDebugStringW in Py_FatalError.

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

file with `str' 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 #4764: With io.open, IOError.filename is set when trying to open a

directory on POSIX systems.

- Issue #4764: IOError.filename is set when trying to open a directory on POSIX

systems.

- Issue #4759: None is now allowed as the first argument of

bytearray.translate(). It was always allowed for bytes.translate().

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

exceptions.

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

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

- 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 #3689: The list reversed iterator now supports __length_hint__

instead of __len__. Behavior now matches other reversed iterators.

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

which there are buffer exports.

- Issue #3845: In PyRun_SimpleFileExFlags avoid invalid memory access with

short file names.

- Issue #5705: os.setuid() would not accept values > 2**31-1 but pwd.getpwnam()

returned them on 64bit platforms.

Library

-------

- Issue #5741: don't disallow "%%" (which is an escape for "%") when setting

a value in SafeConfigParser.

- Issue #5731: Distutils bdist_wininst no longer worked on non-Windows

platforms. Initial patch by Paul Moore.

- Issue #1491431: Fixed distutils.filelist.glob_to_re for edge cases.

Initial fix by Wayne Davison.

- Issue 5471: Fix os.path.expanduser() for $HOME set to '/'.

- Issue 1726172: fix IndexError in the case of and empty response in ftplib.

- In Pdb, prevent the reassignment of __builtin__._ by sys.displayhook on

printing out values.

- Issue #4572: added SEEK_* symbolic constants to io module.

- Issue #1665206 (partially): Move imports in cgitb to the top of the module

instead of performing them in functions. Helps prevent import deadlocking in

threads.

- Issue #5647: MutableSet.__iand__() no longer mutates self during iteration.

- Actually make the SimpleXMLRPCServer CGI handler work.

- Issue #2522: locale.format now checks its first argument to ensure it has

been passed only one pattern, avoiding mysterious errors where it appeared

that it was failing to do localization.

- Issue 2625: added missing iteritems() call to the for loop in

mailbox.MH.get_message().

- Issue #5647: MutableSet.__iand__() no longer mutates self during iteration.

- Issue #5619: Multiprocessing children disobey the debug flag and causes

popups on windows buildbots. Patch applied to work around this issue.

- Issue #5632: Thread.ident was None for the main thread and threads not

created with the threading module.

- Issue #5400: Added patch for multiprocessing on netbsd compilation/support

- Fix and properly document the multiprocessing module's logging

support, expose the internal levels and provide proper usage

examples.

- Issue #5387: Fixed mmap.move crash by integer overflow.

- Issue #5261: Patch multiprocessing's semaphore.c to support context

manager use: "with multiprocessing.Lock()" works now.

- Issue #5177: Multiprocessing's SocketListener class now uses

socket.SO_REUSEADDR on all connections so that the user no longer needs

to wait 120 seconds for the socket to expire.

- Adjusted _tkinter to compile without warnings when WITH_THREAD is not

defined (part of issue #5035).

- Issue #5561: Removed the sys.version_info shortcuts from platform's

python_version() and python_version_tuple() since they produced different

output compared to previous Python versions.

- Issue #5068: Fixed the tarfile._BZ2Proxy.read() method that would loop

forever on incomplete input. That caused tarfile.open() to hang when used

with mode 'r' or 'r:bz2' and a fileobj argument that contained no data or

partial bzip2 compressed data.

- Issue #5536: urllib.urlretrieve makes sure to close the file it's writing to

even if an exception occurs.

- Fix Decimal.__format__ bug that swapped the meanings of the '<' and

'>' alignment characters.

- Issue #1222: locale.format() bug when the thousands separator is a space

character.

- Issue #4792: Prevent a segfault in _tkinter by using the

guaranteed to be safe interp argument given to the PythonCmd in place of

the Tcl interpreter taken from a PythonCmd_ClientData.

- Issue #5193: Guarantee that Tkinter.Text.search returns a string.

- Issue #5385: Fixed mmap crash after resize failure on windows.

- Issue #5179: Fixed subprocess handle leak on failure on windows.

- Issue #4308: httplib.IncompleteRead's repr doesn't include all of the data

all ready received.

- Issue #5401: Fixed a performance problem in mimetypes when ``from mimetypes

import guess_extension`` was used.

- Issue #1733986: Fixed mmap crash in accessing elements of second map object

with same tagname but larger size than first map. (Windows)

- Issue #5386: mmap.write_byte didn't check map size, so it could cause buffer

overrun.

- Issue #5292: Fixed mmap crash on its boundary access m[len(m)].

- Issue #5282: Fixed mmap resize on 32bit windows and unix. When offset > 0,

The file was resized to wrong size.

- Issue #5287: Add exception handling around findCaller() call in logging to

help out IronPython.

- Issue #4524: distutils build_script command failed with --with-suffix=3.

Initial patch by Amaury Forgeot d'Arc.

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

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

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

under NT and OS2. Patch by Philip Jenvey.

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

- Issue #5170: Fixed Unicode output bug in logging and added test case.

This is a regression which did not occur in 2.5.

- 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.

- 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").

- Issue 4920: Fixed .next() vs .__next__() issues in the ABCs for

Iterator and MutableSet.

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

collections.namedtuple() relied on __name__ being defined.

- 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 #3997: zipfiles generated with more than 65536 files could not be

opened with other applications.

- Issue 4816: itertools.combinations() and itertools.product were raising

a ValueError for values of *r* larger than the input iterable. They now

correctly return an empty iterator.

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

cast as floats.

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

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

- Issue #3954: Fix a potential SystemError in _hotshot.logreader error

handling.

- Issue #4574: fix a crash in io.IncrementalNewlineDecoder when a carriage

return encodes to more than one byte in the source encoding (e.g. UTF-16)

and gets split on a chunk 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 #4483: _dbm module now builds on systems with gdbm & gdbm_compat

libs.

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

- 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 #2703: SimpleXMLRPCDispatcher.__init__: Provide default values for

new arguments introduced in 2.5.

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

the tar file was overriden by the gztar one.

- Registered Decimal as a numbers.Number so that isinstance(d, Number) works.

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

producing a ValueError on some platforms.

- Restore Python 2.3 compatibility for decimal.py.

- Issue #1702551: distutils sdist was not excluding VCS directories under

Windows. Inital solution by Guy Dalberto.

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

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

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

works as expected in the interactive environment.

- Issue #4756: zipfile.is_zipfile() now supports file-like objects. Patch by

Gabriel Genellina.

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

function. Original patch by Thomas Heller.

- Issue #4400: .pypirc default generated file was broken in distutils.

- Issue #4736: io.BufferedRWPair's closed property now functions properly.

- Issue #3954: Fix a potential SystemError in _hotshot.logreader error

handling.

- Issue #4163: Use unicode-friendly word splitting in the textwrap functions

when given an unicode string.

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

- 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 #1030250: Distutils created directories even when run with the

--dry-run option.

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

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

Content-Disposition headers.

- Issue #4730: Fixed the cPickle module to handle correctly astral characters

when protocol 0 is used.

- Issue #16278952: plat-mac/videoreader.py now correctly imports MediaDescr

- Issue #1737832 : plat-mac/EasyDialog.py no longer uses the broken aepack

module.

- Issue #1149804: macostools.mkdirs now even works when another process

creates one of the needed subdirectories.

Tools/Demos

-----------

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

Extension Modules

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

- Issue #4301: Patch the logging module to add processName support, remove

_check_logger_class from multiprocessing.

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

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

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

- Issue #4051: Prevent conflict of UNICODE macros in cPickle.

- 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.

Build

-----

- Link the shared python library with $(MODLIBS).

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

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

- Issue #4895: Use _strdup on Windows CE.

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

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

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.

Tests

-----

- Issue #5635: Fix running test_sys with tracing enabled.

- regrtest no longer treats ImportError as equivalent to SkipTest. Imports

that should cause a test to be skipped are now done using import_module

from test support, which does the conversion.

- Issue #5083: New 'gui' resource for regrtest.

What's New in Python 2.6.1

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

*Release date: 04-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 #4367: Python would segfault during compiling when the unicodedata

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

- Issue #4348: Some bytearray methods returned that didn't cause any change to

the bytearray, returned the same bytearray instead of a copy.

- Issue #4317: Fixed a crash in the imageop.rgb2rgb8() function.

- Issue #4230: If ``__getattr__`` is a descriptor, it now functions correctly.

- Issue #4048: The parser module now correctly validates relative imports.

- Issue #4225: ``from __future__ import unicode_literals`` didn't work in an

exec statement.

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

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

- Issue #4209: Enabling unicode_literals and the print_function in the same

__future__ import didn't work.

- On windows, os.chdir given unicode was not working if GetCurrentDirectoryW

returned a path longer than MAX_PATH. (But It's doubtful this code path is

really executed because I cannot move to such directory on win2k)

- Issue #4069: When set.remove(element) is used with a set element, the element

is temporarily replaced with an equivalent frozenset. But the eventual

KeyError would always report the empty frozenset([]) as the missing key. Now

it correctly refers to the initial element.

- Fixed C99 style comments in several files. Python is now C89 compatible

again.

Library

-------

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

exception.

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

the ctypes module is not present.

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

- Issue #3774: Fixed an error when create a Tkinter menu item without command

and then remove it.

- Fixed a modulefinder crash on certain relative imports.

- Issue #4150: Pdb's "up" command now works for generator frames in post-mortem

debugging.

- Issue #4092: Return ArgInfo as promised in the documentation from

inspect.getargvalues.

- Issue #3935: Properly support list subclasses in bisect's C implementation.

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

to claiming it is Mature.

Build

-----

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

- Issue #4289: Remove Cancel button from AdvancedDlg.

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

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

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

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

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

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

C-API

-----

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

Py_UNICODE_ISSPACE macro in an extension module.

Extension Modules

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

- Issue #4365: Add crtassem.h constants to the msvcrt module.

- Issue #4396: The parser module now correctly validates the with statement.

What's New in Python 2.6 final

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

*Release date: 01-Oct-2008*

Core and Builtins

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

- Issue #3967: Fixed a crash in the count() and find() methods of string-like

objects, when the "start" parameter is a huge value.

- Issue #3965: Fixed a crash on Windows when open() is given an invalid

filename or mode, and the filename is a unicode string.

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

Library

-------

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

true singleton object.

- Issue #3895: It was possible to crash the interpreter when an external timer

was used with cProfile that returned an object that could not be converted

into a float.

- Issue #3950: Made turtle respect scale factors.

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

sizes.

- Issue #3879: A regression in urllib.getproxies_enviroment was fixed.

- Issue #3863: Disabled a unit test of fork being called from a thread

when running on platforms known to exhibit OS bugs when attempting that.

Build

-----

- Bug #3989: Package the 2to3 script (as 2to3.py) in the Windows

installer.

- Bug #3887: Package x64 version of CRT for AMD64 Windows binaries.

What's New in Python 2.6 release candidate 2?

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

*Release date: 17-Sep-2008*

Core and Builtins

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

Extension Modules

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

- Security Issue #2: imageop did not validate arguments correctly and could

segfault as a result.

- Issue #3886: Possible integer overflows in the _hashopenssl module were

closed.

Tools/Demos

-----------

- Issue #3850: recursion tests in Misc/find_recursion_limit.py can raise

AttributeError instead of RuntimeError, depending in which C API call

exactly the recursion limit is exceeded. Consequently, both exception types

are caught and silenced.

Build

-----

- Issue #3617: Include a licensing statement regarding the Microsoft

C runtime in the Windows installer.

What's New in Python 2.6 release candidate 1?

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

*Release date: 12-Sep-2008*

Core and Builtins

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

- Issue #3642: Suppress warning in obmalloc when size_t is larger than uint.

- Issue #3743: In a few places, PY_FORMAT_SIZE_T was incorrectly used with

PyString_FromFormat or PyErr_Format to display size_t values. The macro

PY_FORMAT_SIZE_T is designed to select the correct format for the OS

``printf`` function, whereas PyString_FromFormat has an independent

implementation and uses "%zd" on all platforms for size_t values.

This makes a difference on win64, where ``printf`` needs "%Id" to display

64bit values.

- Issue #3634: _weakref.ref(Exception).__init__() gave invalid return value on

error.

- Issue #3777: long() applied to a float object now always return a long

object; previously an int would be returned for small values. the __long__

method is allowed to return either an int or a long, but the behaviour of

float objects should not change to respect backward compatibility.

- Issue #3751: str.rpartition would perform a left-partition when called with

a unicode argument.

- Issue #3683: Fix compilation when --without-threads is given.

- 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 #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.

- 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.

- Silenced another compiler warning about a used but not defined

function 'stringlib_contains_obj'.

- Added warnings on the use of ``__getslice__``, ``__setslice__``, or

``__delslice__``.

- Issue #3678: Correctly pass LDFLAGS and LDLAST to the linker on shared

library targets in the Makefile.

- 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

-----

- Aliased PyObject_Bytes to PyObject_Str.

Library

-------

- Issue #3640: Pickling a list or a dict uses less local variables, to reduce

stack usage in the case of deeply nested objects.

- Issue #3629: Fix sre "bytecode" validator for an end case.

- Issue #3811: The Unicode database was updated to 5.1.

- Issue #3781: Further warnings.catch_warnings() cleanup to prevent

silent misbehaviour when a single instance is nested in multiple

with statements, or when the methods are invoked in the wrong order.

- Issue #3809: Fixed spurious 'test.blah' file left behind by test_logging.

- Issue #3781: Clean up the API for warnings.catch_warnings() by having it

return a list or None rather than a custom object.

- Issue #1638033: Cookie.Morsel gained the httponly attribute.

- 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 #3772: Fixed regression problem in StreamHandler.emit().

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

to the urlparse one. Added a PendingDeprecationWarning in the old

module, it will be deprecated in the future.

- Issue #2562: Fix distutils PKG-INFO writing logic to allow having

non-ascii characters and Unicode in setup.py meta-data.

- Issue #3726: Allow spaces in separators in logging configuration files.

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

path to the Python binary.

- Issue 3602: Moved test.test_support.catch_warning() to

warnings.catch_warnings() along with some API cleanup. Expanding the tests

for catch_warnings() also led to an improvement in the raising of a

DeprecationWarning related to warnings.warn_explicit().

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

- logging: fixed lack of use of encoding attribute specified on a stream.

- Silenced a trivial compiler warning in the sqlite module.

- Fixed two format strings in the _collections module.

- Issue #3703: _fileio.FileIO gave unhelpful error message when trying to open a

directory.

- Issue #3708: os.urandom no longer goes into an infinite loop when passed a

non-integer floating point number.

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

SEM_VALUE_MAX.

Extension Modules

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

- 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.

- sqlite3: Changed docstring of iterdump() to mark method as "Non-standard".

- Issue #3103: Reduced globals symbols used by sqlite3 module and made sure all

remaining ones have "pysqlite_" prefix.

- Issue #3846: Release the GIL during sqlite3_prepare calls. This improves

concurrent access to the same SQLite database from multiple

threads/processes.

Tests

-----

- Issue #3781: Add test.test_support.check_warnings() as a convenience

wrapper for warnings.catch_warnings() that makes it easier to check

that expected warning messages are being reported.

- Issue #3796: Some tests functions were not enabled in test_float.

- Issue #3768: Move test_py3kwarn over to the new API for catch_warnings().

Build

-----

- Issue #3833: Use a different upgrade code for Win64 installers.

- Issue #2271: Set SecureCustomProperties so that installation will properly

use the TARGETDIR even for unprivileged users.

- Allow passing the MSI file name to merge.py.

- Issue #3758: Rename the 'check' target to 'patchcheck' so as to not clash

with GNU build target guidelines.

What's New in Python 2.6 beta 3?

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

*Release date: 20-Aug-2008*

Core and Builtins

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

- Issue #1878: Remove Py_TPFLAGS_HAVE_VERSION_TAG from

Py_TPFLAGS_DEFAULT when not building the core. This means 3rd party

extensions do not automatically benefit from the class attribute

cache; they will have to explicitly add Py_TPFLAGS_HAVE_VERSION_TAG

to their tp_flags field if they care. This is a backwards

compatibility feature; in 3.0, all types will use the cache by

default.

- Keyword arguments can now follow starred arguments. (``f(a, *args,

keyword=23)`` is now valid syntax.)

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

value again.

- Issue #3139: Make buffer-interface thread-safe wrt. PyArg_ParseTuple,

by denying s# to parse objects that have a releasebuffer procedure,

and introducing s*.

- Issue #3537: Fix an assertion failure when an empty but presized dict

object was stored in the freelist.

- Issue #1481296: Make long(float('nan')) and int(float('nan')) raise

ValueError consistently across platforms.

- Issue #3479: On platforms where sizeof(int) is smaller than sizeof(long)

(64bit Unix, for example), unichr() would truncate its argument and return

u'\x00' for unichr(2**32). Now it properly raises an OverflowError.

- Apply security patches from Apple.

- Issue #2542: Now that issubclass() may call arbitrary code, ensure that

PyErr_ExceptionMatches returns 0 when an exception occurs there.

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

average 35% faster (as measured by pybench).

- Issue #2378: An unexpected UnboundLocalError or NameError could appear when

the python debugger steps into a class statement: the free variables (local

variables defined in an outer scope) would be deleted from the outer scope.

- Issue #2620: Overflow checking when allocating or reallocating memory

was not always being done properly in some python types and extension

modules. PyMem_MALLOC, PyMem_REALLOC, PyMem_NEW and PyMem_RESIZE have

all been updated to perform better checks and places in the code that

would previously leak memory on the error path when such an allocation

failed have been fixed.

Library

-------

- Issue #3612: Added some missing basic types in ctypes.wintypes.

- The methods ``is_in_tuple()``, ``is_vararg()``, and ``is_keywordarg()`` of

symtable.Symbol have been deprecated for removal in 3.0 and the next release.

- Issue #2234: distutils failed for some versions of the cygwin compiler. The

version reported by these tools does not necessarily follow the python

version numbering scheme, so the module is less strict when parsing it.

- Issue #2235: Added Py3k warnings for types which will become unhashable

under the stricter __hash__ inheritance rules in 3.0. Several types

which did not meet the rules for hash invariants and were already

unhashable in 3.0 have now been explicitly flagged as unhashable in

2.6 as well (collections.Mapping, collections.Set, unittest.TestSuite,

xml.dom.minidom.NamedNodeMap, numbers.Number, UserList.UserList)

- Update __all__ for cookielib, csv, os, urllib2, and weakref to include things

imported into the module but exposed as part of the module's API.

- Remove an unneeded import of abc.ABCMeta from 'inspect'.

- Remove unneeded imports of 'sys' and 'warnings' from 'io'.

- Remove unneeded imports of 'warnings' from shelve, filecmp, and dummy_thread.

- Issue #3575: Incremental decoder's decode function now takes bytearray

by using 's*' instead of 't#'.

- Issue #2222: Fixed reference leak when occured os.rename()

fails unicode conversion on 2nd parameter. (windows only)

- Issue 2464. urllib2 now supports a malformation in the URL received

in a redirect.

- Silence the DeprecationWarning raised when importing mimetools in

BaseHTTPServer, cgi (and rfc822), httplib.

- Issue #2776: fixed small issue when handling an URL with double slash

after a 302 response in the case of not going through a proxy.

- 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.

- Silence the DeprecationWarning of rfc822 when it is imported by mimetools

since mimetools itself is deprecated. Because modules are cached, all

subsequent imports of rfc822 will not raise a visible DeprecationWarning.

- Issue #3134: shutil referenced undefined WindowsError symbol.

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

menu entries were not deleted.

- Copied the implementation of reduce() to _functools.reduce() to have a

version that did not raise a DeprecationWarning under -3.

- Issue #3205: When iterating over a BZ2File fails allocating memory, raise

a MemoryError rather than silently stop the iteration.

- Issue #3487: sre "bytecode" validator. Passing invalid "re-bytecode"

to _sre.compile() will now be rejected. This should not affect anybody

since the re.compile() function never generates invalid re-bytecode.

- Issue #3436: Make csv.DictReader's fieldnames attribute a property so that

upon first access it can be automatically initialized from the csv file if

it wasn't initialized during instantiation.

- Issue #2338: Create imp.reload() to help with transitioning to Python 3.0 as

the reload() built-in has been removed.

- Changed code in the following modules/packages to remove warnings raised

while running under the ``-3`` flag: aifc, asynchat, asyncore, bdb, bsddb,

ConfigParser, cookielib, csv, difflib, distutils, DocXMLRPCServer, email,

filecmp, fileinput, inspect, logging, modulefinder, pdb, pickle, profile,

pstats, pydoc, re, rlcompleter, SimpleXMLRPCServer, shelve, socket,

subprocess, sqlite3, tarfile, Tkinter, test.test_support, textwrap,

threading, tokenize, traceback, urlparse, wsgiref, xml, xmlrpclib.

- Issue #3039: Fix tarfile.TarFileCompat.writestr() which always

raised an AttributeError.

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

asking for a specific length. This problem only affected files opened

using the new "io" module, not the built-in open() function.

- Issue #3449: Update decimal module to use most recent specification

(v. 1.68) and tests (v. 2.58) from IBM.

- Issue 3437: Bug fix in robotparser parsing of Allow: lines.

- Issue 1592: Improve error reporting when operations are attempted

on a closed shelf.

- Deprecate the "ast" parser function aliases.

- Issue #3120: On 64-bit Windows the subprocess module was truncating handles.

- Issue #3303: Fix a crash in locale.strcoll() when calling it with

invalid arguments.

- Issue #3302: Fix several crashes when calling locale's gettext functions

with None arguments.

- Issue #3389: Allow resolving dotted names for handlers in logging

configuration files.

- Deprecate the sunaudio module for removal in Python 3.0.

- 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 #1857: subprocess.Popen.poll gained an additional _deadstate keyword

argument in python 2.5, this broke code that subclassed Popen to include its