+++++++++++

Python News

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

What's New in Python 2.4.2 final?

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

*Release date: 28-SEP-2005*

Extension Modules

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

- Patches #1298449 and #1298499: Add some missing checks for error

returns in cStringIO.c.

- Patch #1297028: fix segfault if call type on MultibyteCodec,

MultibyteStreamReader, or MultibyteStreamWriter.

Tests

-----

- Fixed failure in test_macfs on Mac OS X 10.4 (Tiger), which

apparently doesn't allow the creation time to be set later than the

modification time. Fixed by changing the test data.

Build

-----

- The Windows .msi files are now compressed using lzx:21. This produces a

significantly smaller installer.

What's New in Python 2.4.2c1

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

*Release date: 21-SEP-2005*

Core and builtins

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

- SF bug #1163563: the original fix for bug #1010677 ("thread Module

Breaks PyGILState_Ensure()") broke badly in the case of multiple

interpreter states; back out that fix and do a better job (see

http://mail.python.org/pipermail/python-dev/2005-June/054258.html

for a longer write-up of the problem).

- On 64-bit platforms, when __len__() returns a value that cannot be

represented as a C int, raise OverflowError.

- SF bug #893549: parsing keyword arguments was broken with a few format

codes.

- Changes donated by Elemental Security to make it work on AIX 5.3

with IBM's 64-bit compiler (SF patch #1284289). This also closes SF

bug #105470: test_pwd fails on 64bit system (Opteron).

- Changes donated by Elemental Security to make it work on HP-UX 11 on

Itanium2 with HP's 64-bit compiler (SF patch #1225212).

- Disallow keyword arguments for type constructors that don't use them

(fixes bug #1119418).

- Forward UnicodeDecodeError into SyntaxError for source encoding errors.

- SF bug #900092: When tracing (e.g. for hotshot), restore 'return' events for

exceptions that cause a function to exit.

- SF bug #1257731: set.discard() and set.remove() did not correctly

handle keys that both inherited from set and defined their own

__hash__() function. Also, changed set.__contains__() to have

identical logic.

- The set() builtin can now properly compute s-=s as an empty set.

- SF bug #1238681: freed pointer is used in longobject.c:long_pow().

- SF bug #1185883: Python's small-object memory allocator took over

a block managed by the platform C library whenever a realloc specified

a small new size. However, there's no portable way to know then how

much of the address space following the pointer is valid, so no

portable way to copy data from the C-managed block into Python's

small-object space without risking a memory fault. Python's small-object

realloc now leaves such blocks under the control of the platform C

realloc.

- Fix garbage collection for set and frozenset objects. SF patch #1200018.

- It is now safe to call PyGILState_Release() before

PyEval_InitThreads() (note that if there is reason to believe there

are multiple threads around you still must call PyEval_InitThreads()

before using the Python API; this fix is for extension modules that

have no way of knowing if Python is multi-threaded yet).

- Typing Ctrl-C whilst raw_input() was waiting in a build with threads

disabled caused a crash.

- Bug #1165306: instancemethod_new allowed the creation of a method

with im_class == im_self == NULL, which caused a crash when called.

Extension Modules

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

- Fix memory leak in posix.access().

- Patch #1213831: Fix typo in unicodedata._getcode.

- Bug #1007046: os.startfile() did not accept unicode strings encoded in

the file system encoding.

- Patch #756021: Special-case socket.inet_aton('255.255.255.255') for

platforms that don't have inet_aton().

- Bug #1215928: Fix bz2.BZ2File.seek() for 64-bit file offsets.

- Bug #1191043: Fix bz2.BZ2File.(x)readlines() for files containing one line

without newlines.

- Bug #728515: mmap.resize() now resizes the file on Unix as it did

on Windows.

- Bug #1234979: For the argument of thread.Lock.acquire, the Windows

implemented treated all integer values except 1 as false.

- Bug #1194181: bz2.BZ2File didn't handle mode 'U' correctly.

- Bug #1166660: The readline module could segfault if hook functions

were set in a different thread than that which called readline.

- weakref proxy has incorrect __nonzero__ behavior. SF bug #1770766.

Library

-------

- Patch #1166948: locale.py: Prefer LC_ALL, LC_CTYPE and LANG over LANGUAGE

to get the correct encoding.

- Patch #1166938: locale.py: Parse LANGUAGE as a colon separated list of

languages.

- Patch #1268314: Cache lines in StreamReader.readlines for performance.

- Bug #1290505: time.strptime() was not invalidating its regex cache when the

locale changed.

- Fix a misuse of str.find() in detection of use of %U or %W in datetime

format.

- Bug #1167128: Fix size of a symlink in a tarfile to be 0.

- Patch #810023: Fix off-by-one bug in urllib.urlretrieve reporthook

functionality.

- Bug #1163178: Make IDNA return an empty string when the input is empty.

- Bug #1121494: distutils.dir_utils.mkpath now accepts Unicode strings.

- Bug #1178484: Return complete lines from codec stream readers

even if there is an exception in later lines, resulting in

correct line numbers for decoding errors in source code.

- Bug #1266283: "lexists" is now in os.path.__all__.

- The sets module can now properly compute s-=s and s^=s as an empty set.

- Bug #1192315: Disallow negative arguments to clear() in pdb.

- Patch #827386: Support absolute source paths in msvccompiler.py.

- Fix a problem in Tkinter introduced by SF patch #869468: delete bogus

__hasattr__ and __delattr__ methods on class Tk that were breaking

Tkdnd.

- Bug #1015140: disambiguated the term "article id" in nntplib docs and

docstrings to either "article number" or "message id".

- Bug #1177468: Don't cache the /dev/urandom file descriptor for os.urandom,

as this can cause problems with apps closing all file descriptors.

- Bug #839151: Fix an attempt to access sys.argv in the warnings module

though this can be missing in embedded interpreters

- Bug #1155638: Fix a bug which affected HTTP 0.9 responses in httplib.

- Bug #1100201: Cross-site scripting was possible on BaseHTTPServer via

error messages.

- Bug #1224621: tokenize module does not detect inconsistent dedents

- Bug #1196315: fix weakref.WeakValueDictionary constructor.

- Bug #1213894: os.path.realpath didn't resolve symlinks that were the first

component of the path.

- distutils.commands.register now encodes the data as UTF-8 before posting

them to PyPI.

- Partial fixes for SF bugs #1163244 and #1175396: If a chunk read by

``codecs.StreamReader.readline()`` has a trailing "\r", read one more

character even if the user has passed a size parameter to get a proper

line ending. Remove the special handling of a "\r\n" that has been split

between two lines.

- Bug #1251300: On UCS-4 builds the "unicode-internal" codec will now complain

about illegal code points. The codec now supports PEP 293 style error

handlers.

- Bug #1235646: ``codecs.StreamRecoder.next()`` now reencodes the data it reads

from the input stream, so that the output is a byte string in the correct

encoding instead of a unicode string.

- Bug #1202493: Fixing SRE parser to handle '{}' as perl does, rather than

considering it exactly like a '*'.

Build

-----

- Patch #1160164: Build zlib.pyd for Itanium.

- Bug #1189330: configure did not correctly determine the necessary

value of LINKCC if python was built with GCC 4.0.

- Upgrade Windows build to zlib 1.2.3 which eliminates a potential security

vulnerability in zlib 1.2.1 and 1.2.2.

Documentation

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

- Bug #1274828: Document os.path.splitunc().

- Bug #1190204: Clarify which directories are searched by site.py.

- Bug #1193849: Clarify os.path.expanduser() documentation.

- Bug #1243192: re.UNICODE and re.LOCALE affect \d, \D, \s and \S.

- Bug #755617: Document the effects of os.chown() on Windows.

- Patch #1180012: The documentation for modulefinder is now in the library reference.

- Patch #1213031: Document that os.chown() accepts argument values of -1.

- Bug #1190563: Document os.waitpid() return value with WNOHANG flag.

- Bug #1175022: Correct the example code for property().

Tools/Demos

-----------

- Bug #1072853: pindent.py used an uninitialized variable.

What's New in Python 2.4.1 final?

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

*Release date: 30-MAR-2005*

Core and builtins

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

- Move exception finalisation later in the shutdown process - this

fixes the crash seen in bug #1165761

Tests

-----

- SF patch 1167316: doctest.py fails self-test if run directly.

Build

-----

- SF patch 1171767: Darwin 8's headers are anal about POSIX compliance,

and linking has changed (prebinding is now deprecated, and libcc_dynamic

no longer exists). This configure patch makes things right.

What's New in Python 2.4.1c2?

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

*Release date: 17-MAR-2005*

Library

-------

- Fixed decimal operator and comparison methods to return NotImplemented

instead of raising a TypeError when interacting with other types.

Allows other classes to successfully implement __radd__ style methods.

- Bug #1163325: Decimal infinities failed to hash. Attempting to

hash a NaN raised an InvalidOperation instead of a TypeError.

- Bug #1160802: can't build Zope on Windows with 2.4.1c1. The

``MSVCCompiler`` class in distutils forgot to record that it was

initialized, and continued adding redundant entries to the system

``PATH`` environment variable until ``putenv()`` complained about the

size. This only affected building projects with many C extensions,

and only on Windows using Microsoft's compiler. This wasn't visible

before because a bugfix first included in 2.4.1c1 provoked it (bug

#1110478: revert os.environ.update to do putenv again).

- Bug #1156259: Seeking in codecs.reader was broken, now fixed.

Tests

-----

- Fix the test for socket.getfqdn() in test_socket to also consider the host

name returned by socket.gethostname() a valid return value for getfqdn().

Also clarified the wording of docs and docstring that this is the case.

Extensions Modules

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

- os.access now supports Unicode path names on non-Win32 systems.

What's New in Python 2.4.1c1?

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

*Release date: 10-MAR-2005*

Core and builtins

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

- Bug #1155938: new style classes did not verify that __init__()

returns None.

- Bug #723201: Raise a TypeError for passing bad objects to 'L' format.

- Bug #1124295: the __name__ attribute of file objects was

inadvertently made inaccessible in restricted mode.

- Bug #1074011: closing sys.std{out,err} now causes a flush() and

an ferror() call.

- Bug #1085744: Add missing overflow check to PySequence_Tuple().

Make resize schedule linear (amortized).

- marshal.dumps() no longer crashes when the optional argument ``version``

is provided.

Extension Modules

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

- Patches #925152, #1118602: Avoid reading after the end of the buffer

in pyexpat.GetInputContext.

- Patch #1093585: raise a ValueError for negative history items in readline.

{remove_history,replace_history}

Library

-------

- Patch #1075887: Don't require MSVC in distutils if there is nothing

to build.

- Patch #1103407: Properly deal with tarfile iterators when untarring

symbolic links on Windows.

- Patch #1117454: Remove code to special-case cookies without values

in LWPCookieJar.

- Patch #1117339: Add cookielib special name tests.

- Patch #1112812: Make bsddb/__init__.py more friendly for modulefinder.

- Patch #1121234: Properly cleanup _exit and tkerror commands.

- Applied a security fix to SimpleXMLRPCserver (PSF-2005-001). This

disables recursive traversal through instance attributes, which can

be exploited in various ways.

- Bug #1110478: Revert os.environ.update to do putenv again.

- Bug #1103844: fix distutils.install.dump_dirs() with negated options.

- Bug #1067732: wininst --install-script doesn't leave residual files anymore.

- StringIO.truncate() now correctly adjusts the size attribute.

(Bug #951915).

- The decimal module wouldn't run on builds without threads (Bug #1083645).

- Bug #1086555: Fix leak in syslog module.

- atexit.register no longer references the sys module before importing it.

(Bug #1083202).

- unittest.TestCase.run() and unittest.TestSuite.run() can now be successfully

extended or overridden by subclasses. Formerly, the subclassed method would

be ignored by the rest of the module. (Bug #1078905).

- Bug #1076985: ``codecs.StreamReader.readline()`` now calls ``read()`` only

once when a size argument is given. This prevents a buffer overflow in the

tokenizer with very long source lines.

- Bug #1083110: ``zlib.decompress.flush()`` would segfault if called immediately

after creating the object, without any intervening ``.decompress()`` calls.

- Bug #1149508: ``textwrap`` now handles hyphenated numbers (eg. "2004-03-05")

correctly.

Build

-----

- Bug #1158607: Build with --disable-unicode again.

- term.h is now properly detected again.

- Check for tzset no longer dependent on tm->tm_zone to exist in the struct

(not required by either ISO C nor the UNIX 2 spec).

Tests for sanity in tzname when HAVE_TZNAME defined were also defined.

Closes bug #1096244. Thanks Gregory Bond.

Windows

-------

- Bug #1076861: The IDLE shortcut is now correct even if the target

directory contains a space.

- Bug #1085208 and similar: The installer does not fail anymore if

VBScript is not available on the target machine, not installed

properly, or outdated; the MSI package now does not rely on VB

anymore.

Macintosh

---------

- Bug #1091468: make frameworkinstall now works with DESTROOT builds

- On 10.3 and later extensions are built with -undefined dynamic_lookup.

This ensures that extensions can be built in older versions of Python after

a newer framework has been installed. In addition, an extension will not

accidentally pull in another copy of the Python interpreter.

On 10.2 and earlier (or if MACOSX_DEPLOYMENT_TARGET is set to a value <= 10.2)

extensions are linked directly to the dylib in the framework, in stead

of against the framework itself. This ensures that extensions can be built

in older versions of Python after a newer framework has been installed.

- PackageManager and the underlying pimp.py module have been updated to

version 0.5, which greatly simplifies maintainance of the package

databases.

Documentation

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

- Remove all latent references for "Macintosh" that referred to semantics for

Mac OS 9 and change to reflect the state for OS X.

Closes patch #1095802. Thanks Jack Jansen.

What's New in Python 2.4 final?

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

*Release date: 30-NOV-2004*

Core and builtins

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

- Bug 875692: Improve signal handling, especially when using threads, by

forcing an early re-execution of PyEval_EvalFrame() "periodic" code when

things_to_do is not cleared by Py_MakePendingCalls().

What's New in Python 2.4 (release candidate 1)

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

*Release date: 18-NOV-2004*

Core and builtins

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

- Bug 1061968: Fixes in 2.4a3 to address thread bug 1010677 reintroduced

the years-old thread shutdown race bug 225673. Numeric history lesson

aside, all bugs in all three reports are fixed now.

Library

-------

- Bug 1052242: If exceptions are raised by an atexit handler function an

attempt is made to execute the remaining handlers. The last exception

raised is re-raised.

- ``doctest``'s new support for adding ``pdb.set_trace()`` calls to

doctests was broken in a dramatic but shallow way. Fixed.

- Bug 1065388: ``calendar``'s ``day_name``, ``day_abbr``, ``month_name``,

and ``month_abbr`` attributes emulate sequences of locale-correct

spellings of month and day names. Because the locale can change at

any time, the correct spelling is recomputed whenever one of these is

indexed. In the worst case, the index may be a slice object, so these

recomputed every day or month name each time they were indexed. This is

much slower than necessary in the usual case, when the index is just an

integer. In that case, only the single spelling needed is recomputed

now; and, when the index is a slice object, only the spellings needed

by the slice are recomputed now.

- Patch 1061679: Added ``__all__`` to pickletools.py.

Build

-----

- Bug 1034277 / Patch 1035255: Remove compilation of core against CoreServices

and CoreFoundation on OS X. Involved removing PyMac_GetAppletScriptFile()

which has no known users. Thanks Bob Ippolito.

C API

-----

- The PyRange_New() function is deprecated.

What's New in Python 2.4 beta 2?

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

*Release date: 03-NOV-2004*

License

-------

The Python Software Foundation changed the license under which Python

is released, to remove Python version numbers. There were no other

changes to the license. So, for example, wherever the license for

Python 2.3 said "Python 2.3", the new license says "Python". The

intent is to make it possible to refer to the PSF license in a more

durable way. For example, some people say they're confused by that

the Open Source Initiative's entry for the Python Software Foundation

License::

http://www.opensource.org/licenses/PythonSoftFoundation.php

says "Python 2.1.1" all over it, wondering whether it applies only

to Python 2.1.1.

The official name of the new license is the Python Software Foundation

License Version 2.

Core and builtins

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

- Bug #1055820 Cyclic garbage collection was not protecting against that

calling a live weakref to a piece of cyclic trash could resurrect an

insane mutation of the trash if any Python code ran during gc (via

running a dead object's __del__ method, running another callback on a

weakref to a dead object, or via any Python code run in any other thread

that managed to obtain the GIL while a __del__ or callback was running

in the thread doing gc). The most likely symptom was "impossible"

``AttributeEror`` exceptions, appearing seemingly at random, on weakly

referenced objects. The cure was to clear all weakrefs to unreachable

objects before allowing any callbacks to run.

- Bug #1054139 _PyString_Resize() now invalidates its cached hash value.

Extension Modules

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

- Bug #1048870: the compiler now generates distinct code objects for

functions with identical bodies. This was producing confusing

traceback messages which pointed to the function where the code

object was first defined rather than the function being executed.

Library

-------

- Patch #1056967 changes the semantics of Template.safe_substitute() so that

no ValueError is raised on an 'invalid' match group. Now the delimiter is

returned.

- Bug #1052503 pdb.runcall() was not passing along keyword arguments.

- Bug #902037: XML.sax.saxutils.prepare_input_source() now combines relative

paths with a base path before checking os.path.isfile().

- The whichdb module can now be run from the command line.

- Bug #1045381: time.strptime() can now infer the date using %U or %W (week of

the year) when the day of the week and year are also specified.

- Bug #1048816: fix bug in Ctrl-K at start of line in curses.textpad.Textbox

- Bug #1017553: fix bug in tarfile.filemode()

- Patch #737473: fix bug that old source code is shown in tracebacks even if

the source code is updated and reloaded.

Build

-----

- Patch #1044395: --enable-shared is allowed in FreeBSD also.

What's New in Python 2.4 beta 1?

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

*Release date: 15-OCT-2004*

Core and builtins

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

- Patch #975056: Restartable signals were not correctly disabled on

BSD systems. Consistently use PyOS_setsig() instead of signal().

- The internal portable implementation of thread-local storage (TLS), used

by the ``PyGILState_Ensure()``/``PyGILState_Release()`` API, was not

thread-correct. This could lead to a variety of problems, up to and

including segfaults. See bug 1041645 for an example.

- Added a command line option, -m module, which searches sys.path for the

module and then runs it. (Contributed by Nick Coghlan.)

- The bytecode optimizer now folds tuples of constants into a single

constant.

- SF bug #513866: Float/long comparison anomaly. Prior to 2.4b1, when

an integer was compared to a float, the integer was coerced to a float.

That could yield spurious overflow errors (if the integer was very

large), and to anomalies such as

``long(1e200)+1 == 1e200 == long(1e200)-1``. Coercion to float is no

longer performed, and cases like ``long(1e200)-1 < 1e200``,

``long(1e200)+1 > 1e200`` and ``(1 << 20000) > 1e200`` are computed

correctly now.

Extension modules

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

- ``collections.deque`` objects didn't play quite right with garbage

collection, which could lead to a segfault in a release build, or

an assert failure in a debug build. Also, added overflow checks,

better detection of mutation during iteration, and shielded deque

comparisons from unusual subclass overrides of the __iter__() method.

Library

-------

- Patch 1046644: distutils build_ext grew two new options - --swig for

specifying the swig executable to use, and --swig-opts to specify

options to pass to swig. --swig-opts="-c++" is the new way to spell

--swig-cpp.

- Patch 983206: distutils now obeys environment variable LDSHARED, if

it is set.

- Added Peter Astrand's subprocess.py module. See PEP 324 for details.

- time.strptime() now properly escapes timezones and all other locale-specific

strings for regex-specific symbols. Was breaking under Japanese Windows when

the timezone was specified as "Tokyo (standard time)".

Closes bug #1039270.

- Updates for the email package:

+ email.Utils.formatdate() grew a 'usegmt' argument for HTTP support.

+ All deprecated APIs that in email 2.x issued warnings have been removed:

_encoder argument to the MIMEText constructor, Message.add_payload(),

Utils.dump_address_pair(), Utils.decode(), Utils.encode()

+ New deprecations: Generator.__call__(), Message.get_type(),

Message.get_main_type(), Message.get_subtype(), the 'strict' argument to

the Parser constructor. These will be removed in email 3.1.

+ Support for Python earlier than 2.3 has been removed (see PEP 291).

+ All defect classes have been renamed to end in 'Defect'.

+ Some FeedParser fixes; also a MultipartInvariantViolationDefect will be

added to messages that claim to be multipart but really aren't.

+ Updates to documentation.

- re's findall() and finditer() functions now take an optional flags argument

just like the compile(), search(), and match() functions. Also, documented

the previously existing start and stop parameters for the findall() and

finditer() methods of regular expression objects.

- rfc822 Messages now support iterating over the headers.

- The (undocumented) tarfile.Tarfile.membernames has been removed;

applications should use the getmember function.

- httplib now offers symbolic constants for the HTTP status codes.

- SF bug #1028306: Trying to compare a ``datetime.date`` to a

``datetime.datetime`` mistakenly compared only the year, month and day.

Now it acts like a mixed-type comparison: ``False`` for ``==``,

``True`` for ``!=``, and raises ``TypeError`` for other comparison

operators. Because datetime is a subclass of date, comparing only the

base class (date) members can still be done, if that's desired, by

forcing using of the approprate date method; e.g.,

``a_date.__eq__(a_datetime)`` is true if and only if the year, month

and day members of ``a_date`` and ``a_datetime`` are equal.

- bdist_rpm now supports command line options --force-arch,

{pre,post}-install, {pre,post}-uninstall, and

{prep,build,install,clean,verify}-script.

- SF patch #998993: The UTF-8 and the UTF-16 stateful decoders now support

decoding incomplete input (when the input stream is temporarily exhausted).

``codecs.StreamReader`` now implements buffering, which enables proper

readline support for the UTF-16 decoders. ``codecs.StreamReader.read()``

has a new argument ``chars`` which specifies the number of characters to

return. ``codecs.StreamReader.readline()`` and

``codecs.StreamReader.readlines()`` have a new argument ``keepends``.

Trailing "\n"s will be stripped from the lines if ``keepends`` is false.

- The documentation for doctest is greatly expanded, and now covers all

the new public features (of which there are many).

- ``doctest.master`` was put back in, and ``doctest.testmod()`` once again

updates it. This isn't good, because every ``testmod()`` call

contributes to bloating the "hidden" state of ``doctest.master``, but

some old code apparently relies on it. For now, all we can do is

encourage people to stitch doctests together via doctest's unittest

integration features instead.

- httplib now handles ipv6 address/port pairs.

- SF bug #1017864: ConfigParser now correctly handles default keys,

processing them with ``ConfigParser.optionxform`` when supplied,

consistent with the handling of config file entries and runtime-set

options.

- SF bug #997050: Document, test, & check for non-string values in

ConfigParser. Moved the new string-only restriction added in

rev. 1.65 to the SafeConfigParser class, leaving existing

ConfigParser & RawConfigParser behavior alone, and documented the

conditions under which non-string values work.

Build

-----

- Building on darwin now includes /opt/local/include and /opt/local/lib for

building extension modules. This is so as to include software installed as

a DarwinPorts port <http://darwinports.opendarwin.org/>

- pyport.h now defines a Py_IS_NAN macro. It works as-is when the

platform C computes true for ``x != x`` if and only if X is a NaN.

Other platforms can override the default definition with a platform-

specific spelling in that platform's pyconfig.h. You can also override

pyport.h's default Py_IS_INFINITY definition now.

C API

-----

- SF patch 1044089: New function ``PyEval_ThreadsInitialized()`` returns

non-zero if PyEval_InitThreads() has been called.

- The undocumented and unused extern int ``_PyThread_Started`` was removed.

- The C API calls ``PyInterpreterState_New()`` and ``PyThreadState_New()``

are two of the very few advertised as being safe to call without holding

the GIL. However, this wasn't true in a debug build, as bug 1041645

demonstrated. In a debug build, Python redirects the ``PyMem`` family

of calls to Python's small-object allocator, to get the benefit of

its extra debugging capabilities. But Python's small-object allocator

isn't threadsafe, relying on the GIL to avoid the expense of doing its

own locking. ``PyInterpreterState_New()`` and ``PyThreadState_New()``

call the platform ``malloc()`` directly now, regardless of build type.

- PyLong_AsUnsignedLong[Mask] now support int objects as well.

- SF patch #998993: ``PyUnicode_DecodeUTF8Stateful`` and

``PyUnicode_DecodeUTF16Stateful`` have been added, which implement stateful

decoding.

Tests

-----

- test__locale ported to unittest

Mac

---

- ``plistlib`` now supports non-dict root objects. There is also a new

interface for reading and writing plist files: ``readPlist(pathOrFile)``

and ``writePlist(rootObject, pathOrFile)``

Tools/Demos

-----------

- The text file comparison scripts ``ndiff.py`` and ``diff.py`` now

read the input files in universal-newline mode. This spares them

from consuming a great deal of time to deduce the useless result that,

e.g., a file with Windows line ends and a file with Linux line ends

have no lines in common.

What's New in Python 2.4 alpha 3?

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

*Release date: 02-SEP-2004*

Core and builtins

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

- SF patch #1007189: ``from ... import ...`` statements now allow the name

list to be surrounded by parentheses.

- Some speedups for long arithmetic, thanks to Trevor Perrin. Gradeschool

multiplication was sped a little by optimizing the C code. Gradeschool

squaring was sped by about a factor of 2, by exploiting that about half

the digit products are duplicates in a square. Because exponentiation

uses squaring often, this also speeds long power. For example, the time

to compute 17**1000000 dropped from about 14 seconds to 9 on my box due

to this much. The cutoff for Karatsuba multiplication was raised,

since gradeschool multiplication got quicker, and the cutoff was

aggressively small regardless. The exponentiation algorithm was switched

from right-to-left to left-to-right, which is more efficient for small

bases. In addition, if the exponent is large, the algorithm now does

5 bits (instead of 1 bit) at a time. That cut the time to compute

17**1000000 on my box in half again, down to about 4.5 seconds.

- OverflowWarning is no longer generated. PEP 237 scheduled this to

occur in Python 2.3, but since OverflowWarning was disabled by default,

nobody realized it was still being generated. On the chance that user

code is still using them, the Python builtin OverflowWarning, and

corresponding C API PyExc_OverflowWarning, will exist until Python 2.5.

- Py_InitializeEx has been added.

- Fix the order of application of decorators. The proper order is bottom-up;

the first decorator listed is the last one called.

- SF patch #1005778. Fix a seg fault if the list size changed while

calling list.index(). This could happen if a rich comparison function

modified the list.

- The ``func_name`` (a.k.a. ``__name__``) attribute of user-defined

functions is now writable.

- code_new (a.k.a new.code()) now checks its arguments sufficiently

carefully that passing them on to PyCode_New() won't trigger calls

to Py_FatalError() or PyErr_BadInternalCall(). It is still the case

that the returned code object might be entirely insane.

- Subclasses of string can no longer be interned. The semantics of

interning were not clear here -- a subclass could be mutable, for

example -- and had bugs. Explicitly interning a subclass of string

via intern() will raise a TypeError. Internal operations that attempt

to intern a string subclass will have no effect.

- Bug 1003935: xrange() could report bogus OverflowErrors. Documented

what xrange() intends, and repaired tests accordingly.

Extension modules

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

- difflib now supports HTML side-by-side diff.

- os.urandom has been added for systems that support sources of random

data.

- Patch 1012740: truncate() on a writeable cStringIO now resets the

position to the end of the stream. This is consistent with the original

StringIO module and avoids inadvertently resurrecting data that was

supposed to have been truncated away.

- Added socket.socketpair().

- Added CurrentByteIndex, CurrentColumnNumber, CurrentLineNumber

members to xml.parsers.expat.XMLParser object.

- The mpz, rotor, and xreadlines modules, all deprecated in earlier

versions of Python, have now been removed.

Library

-------

- Patch #934356: if a module defines __all__, believe that rather than using

heuristics for filtering out imported names.

- Patch #941486: added os.path.lexists(), which returns True for broken

symlinks, unlike os.path.exists().

- the random module now uses os.urandom() for seeding if it is available.

Added a new generator based on os.urandom().

- difflib and diff.py can now generate HTML.

- bdist_rpm now includes version and release in the BuildRoot, and

replaces - by ``_`` in version and release.

- distutils build/build_scripts now has an -e option to specify the

path to the Python interpreter for installed scripts.

- PEP 292 classes Template and SafeTemplate are added to the string module.

- tarfile now generates GNU tar files by default.

- HTTPResponse has now a getheaders method.

- Patch #1006219: let inspect.getsource handle '@' decorators. Thanks Simon

Percivall.

- logging.handlers.SMTPHandler.date_time has been removed;

the class now uses email.Utils.formatdate to generate the time stamp.

- A new function tkFont.nametofont was added to return an existing

font. The Font class constructor now has an additional exists argument

which, if True, requests to return/configure an existing font, rather

than creating a new one.

- Updated the decimal package's min() and max() methods to match the

latest revision of the General Decimal Arithmetic Specification.

Quiet NaNs are ignored and equal values are sorted based on sign

and exponent.

- The decimal package's Context.copy() method now returns deep copies.

- Deprecated sys.exitfunc in favor of the atexit module. The sys.exitfunc

attribute will be kept around for backwards compatibility and atexit

will just become the one preferred way to do it.

- patch #675551: Add get_history_item and replace_history_item functions

to the readline module.

- bug #989672: pdb.doc and the help messages for the help_d and help_u methods

of the pdb.Pdb class gives have been corrected. d(own) goes to a newer

frame, u(p) to an older frame, not the other way around.

- bug #990669: os.path.realpath() will resolve symlinks before normalizing the

path, as normalizing the path may alter the meaning of the path if it

contains symlinks.

- bug #851123: shutil.copyfile will raise an exception when trying to copy a

file onto a link to itself. Thanks Gregory Ball.

- bug #570300: Fix inspect to resolve file locations using os.path.realpath()

so as to properly list all functions in a module when the module itself is

reached through a symlink. Thanks Johannes Gijsbers.

- doctest refactoring continued. See the docs for details. As part of

this effort, some old and little- (never?) used features are now

deprecated: the Tester class, the module is_private() function, and the

isprivate argument to testmod(). The Tester class supplied a feeble

"by hand" way to combine multiple doctests, if you knew exactly what

you were doing. The newer doctest features for unittest integration

already did a better job of that, are stronger now than ever, and the

new DocTestRunner class is a saner foundation if you want to do it by

hand. The "private name" filtering gimmick was a mistake from the

start, and testmod() changed long ago to ignore it by default. If

you want to filter out tests, the new DocTestFinder class can be used

to return a list of all doctests, and you can filter that list by

any computable criteria before passing it to a DocTestRunner instance.

- Bug #891637, patch #1005466: fix inspect.getargs() crash on def foo((bar)).

Tools/Demos

-----------

- IDLE's shortcut keys for windows are now case insensitive so that

Control-V works the same as Control-v.

- pygettext.py: Generate POT-Creation-Date header in ISO format.

Build

-----

- Backward incompatibility: longintrepr.h now triggers a compile-time

error if SHIFT (the number of bits in a Python long "digit") isn't

divisible by 5. This new requirement allows simple code for the new

5-bits-at-a-time long_pow() implementation. If necessary, the

restriction could be removed (by complicating long_pow(), or by

falling back to the 1-bit-at-a-time algorithm), but there are no

plans to do so.

- bug #991962: When building with --disable-toolbox-glue on Darwin no

attempt to build Mac-specific modules occurs.

- The --with-tsc flag to configure to enable VM profiling with the

processor's timestamp counter now works on PPC platforms.

- patch #1006629: Define _XOPEN_SOURCE to 500 on Solaris 8/9 to match

GCC's definition and avoid redefinition warnings.

- Detect pthreads support (provided by gnu pth pthread emulation) on

GNU/k*BSD systems.

- bug #1005737, #1007249: Fixed several build problems and warnings

found on old/legacy C compilers of HP-UX, IRIX and Tru64.

C API

-----

..

Documentation

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

- patch #1005936, bug #1009373: fix index entries which contain

an underscore when viewed with Acrobat.

- bug #990669: os.path.normpath may alter the meaning of a path if

it contains symbolic links. This has been documented in a comment

since 1992, but is now in the library reference as well.

New platforms

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