Python History
--------------

This file contains the release messages for previous Python releases.
As you read on you go back to the dark ages of Python's history.
(Note: news about 2.5c2 and later 2.5 releases is in the Misc/NEWS
file of the release25-maint branch.)


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


What's New in Python 2.5 release candidate 1?
=============================================

*Release date: 17-AUG-2006*

Core and builtins
-----------------

- Unicode objects will no longer raise an exception when being
  compared equal or unequal to a string and a UnicodeDecodeError
  exception occurs, e.g. as result of a decoding failure.

  Instead, the equal (==) and unequal (!=) comparison operators will
  now issue a UnicodeWarning and interpret the two objects as
  unequal. The UnicodeWarning can be filtered as desired using
  the warning framework, e.g. silenced completely, turned into an
  exception, logged, etc.

  Note that compare operators other than equal and unequal will still
  raise UnicodeDecodeError exceptions as they've always done.

- Fix segfault when doing string formatting on subclasses of long.

- Fix bug related to __len__ functions using values > 2**32 on 64-bit machines
  with new-style classes.

- Fix bug related to __len__ functions returning negative values with
  classic classes.

- Patch #1538606, Fix __index__() clipping.  There were some problems
  discovered with the API and how integers that didn't fit into Py_ssize_t
  were handled.  This patch attempts to provide enough alternatives
  to effectively use __index__.

- Bug #1536021: __hash__ may now return long int; the final hash
  value is obtained by invoking hash on the long int.

- Bug #1536786: buffer comparison could emit a RuntimeWarning.

- Bug #1535165: fixed a segfault in input() and raw_input() when
  sys.stdin is closed.

- On Windows, the PyErr_Warn function is now exported from
  the Python dll again.

- Bug #1191458: tracing over for loops now produces a line event
  on each iteration.  Fixing this problem required changing the .pyc
  magic number.  This means that .pyc files generated before 2.5c1
  will be regenerated.

- Bug #1333982: string/number constants were inappropriately stored
  in the byte code and co_consts even if they were not used, ie
  immediately popped off the stack.

- Fixed a reference-counting problem in property().


Library
-------

- Fix a bug in the ``compiler`` package that caused invalid code to be
  generated for generator expressions.

- The distutils version has been changed to 2.5.0. The change to
  keep it programmatically in sync with the Python version running
  the code (introduced in 2.5b3) has been reverted. It will continue
  to be maintained manually as static string literal.

- If the Python part of a ctypes callback function returns None,
  and this cannot be converted to the required C type, an exception is
  printed with PyErr_WriteUnraisable.  Before this change, the C
  callback returned arbitrary values to the calling code.

- The __repr__ method of a NULL ctypes.py_object() no longer raises
  an exception.

- uuid.UUID now has a bytes_le attribute. This returns the UUID in
  little-endian byte order for Windows. In addition, uuid.py gained some
  workarounds for clocks with low resolution, to stop the code yielding
  duplicate UUIDs.

- Patch #1540892: site.py Quitter() class attempts to close sys.stdin
  before raising SystemExit, allowing IDLE to honor quit() and exit().

- Bug #1224621: make tabnanny recognize IndentationErrors raised by tokenize.

- Patch #1536071: trace.py should now find the full module name of a
  file correctly even on Windows.

- logging's atexit hook now runs even if the rest of the module has
  already been cleaned up.

- Bug #1112549, fix DoS attack on cgi.FieldStorage.

- Bug #1531405, format_exception no longer raises an exception if
  str(exception) raised an exception.

- Fix a bug in the ``compiler`` package that caused invalid code to be
  generated for nested functions.


Extension Modules
-----------------

- Patch #1511317: don't crash on invalid hostname (alias) info.

- Patch #1535500: fix segfault in BZ2File.writelines and make sure it
  raises the correct exceptions.

- Patch # 1536908: enable building ctypes on OpenBSD/AMD64.  The
  '-no-stack-protector' compiler flag for OpenBSD has been removed.

- Patch #1532975 was applied, which fixes Bug #1533481: ctypes now
  uses the _as_parameter_ attribute when objects are passed to foreign
  function calls.  The ctypes version number was changed to 1.0.1.

- Bug #1530559, struct.pack raises TypeError where it used to convert.
  Passing float arguments to struct.pack when integers are expected
  now triggers a DeprecationWarning.


Tests
-----

- test_socketserver should now work on cygwin and not fail sporadically
  on other platforms.

- test_mailbox should now work on cygwin versions 2006-08-10 and later.

- Bug #1535182: really test the xreadlines() method of bz2 objects.

- test_threading now skips testing alternate thread stack sizes on
  platforms that don't support changing thread stack size.


Documentation
-------------

- Patch #1534922: unittest docs were corrected and enhanced.


Build
-----

- Bug #1535502, build _hashlib on Windows, and use masm assembler
  code in OpenSSL.

- Bug #1534738, win32 debug version of _msi should be _msi_d.pyd.

- Bug #1530448, ctypes build failure on Solaris 10 was fixed.


C API
-----

- New API for Unicode rich comparisons: PyUnicode_RichCompare()

- Bug #1069160.  Internal correctness changes were made to
  ``PyThreadState_SetAsyncExc()``.  A test case was added, and
  the documentation was changed to state that the return value
  is always 1 (normal) or 0 (if the specified thread wasn't found).


What's New in Python 2.5 beta 3?
================================

*Release date: 03-AUG-2006*

Core and builtins
-----------------

- _PyWeakref_GetWeakrefCount() now returns a Py_ssize_t; it previously
  returned a long (see PEP 353).

- Bug #1515471: string.replace() accepts character buffers again.

- Add PyErr_WarnEx() so C code can pass the stacklevel to warnings.warn().
  This provides the proper warning for struct.pack().
  PyErr_Warn() is now deprecated in favor of PyErr_WarnEx().

- Patch #1531113: Fix augmented assignment with yield expressions.
  Also fix a SystemError when trying to assign to yield expressions.

- Bug #1529871: The speed enhancement patch #921466 broke Python's compliance
  with PEP 302.  This was fixed by adding an ``imp.NullImporter`` type that is
  used in ``sys.path_importer_cache`` to cache non-directory paths and avoid
  excessive filesystem operations during imports.

- Bug #1521947: When checking for overflow, ``PyOS_strtol()`` used some
  operations on signed longs that are formally undefined by C.
  Unfortunately, at least one compiler now cares about that, so complicated
  the code to make that compiler happy again.

- Bug #1524310: Properly report errors from FindNextFile in os.listdir.

- Patch #1232023: Stop including current directory in search
  path on Windows.

- Fix some potential crashes found with failmalloc.

- Fix warnings reported by Klocwork's static analysis tool.

- Bug #1512814, Fix incorrect lineno's when code within a function
  had more than 255 blank lines.

- Patch #1521179: Python now accepts the standard options ``--help`` and
  ``--version`` as well as ``/?`` on Windows.

- Bug #1520864: unpacking singleton tuples in a 'for' loop (for x, in) works
  again.  Fixing this problem required changing the .pyc magic number.
  This means that .pyc files generated before 2.5b3 will be regenerated.

- Bug #1524317:  Compiling Python ``--without-threads`` failed.
  The Python core compiles again, and, in a build without threads, the
  new ``sys._current_frames()`` returns a dictionary with one entry,
  mapping the faux "thread id" 0 to the current frame.

- Bug #1525447: build on MacOS X on a case-sensitive filesystem.


Library
-------

- Fix #1693149.  Now you can pass several modules separated by
  comma to trace.py in the same --ignore-module option.

- Correction of patch #1455898: In the mbcs decoder, set final=False
  for stream decoder, but final=True for the decode function.

- os.urandom no longer masks unrelated exceptions like SystemExit or
  KeyboardInterrupt.

- Bug #1525866: Don't copy directory stat times in
  shutil.copytree on Windows

- Bug #1002398: The documentation for os.path.sameopenfile now correctly
  refers to file descriptors, not file objects.

- The renaming of the xml package to xmlcore, and the import hackery done
  to make it appear at both names, has been removed.  Bug #1511497,
  #1513611, and probably others.

- Bug #1441397: The compiler module now recognizes module and function
  docstrings correctly as it did in Python 2.4.

- Bug #1529297:  The rewrite of doctest for Python 2.4 unintentionally
  lost that tests are sorted by name before being run.  This rarely
  matters for well-written tests, but can create baffling symptoms if
  side effects from one test to the next affect outcomes.  ``DocTestFinder``
  has been changed to sort the list of tests it returns.

- The distutils version has been changed to 2.5.0, and is now kept
  in sync with sys.version_info[:3].

- Bug #978833: Really close underlying socket in _socketobject.close.

- Bug #1459963: urllib and urllib2 now normalize HTTP header names with
  title().

- Patch #1525766: In pkgutil.walk_packages, correctly pass the onerror callback
  to recursive calls and call it with the failing package name.

- Bug #1525817: Don't truncate short lines in IDLE's tool tips.

- Patch #1515343: Fix printing of deprecated string exceptions with a
  value in the traceback module.

- Resync optparse with Optik 1.5.3: minor tweaks for/to tests.

- Patch #1524429: Use repr() instead of backticks in Tkinter again.

- Bug #1520914: Change time.strftime() to accept a zero for any position in its
  argument tuple.  For arguments where zero is illegal, the value is forced to
  the minimum value that is correct.  This is to support an undocumented but
  common way people used  to fill in inconsequential information in the time
  tuple pre-2.4.

- Patch #1220874: Update the binhex module for Mach-O.

- The email package has improved RFC 2231 support, specifically for
  recognizing the difference between encoded (name*0*=<blah>) and non-encoded
  (name*0=<blah>) parameter continuations.  This may change the types of
  values returned from email.message.Message.get_param() and friends.
  Specifically in some cases where non-encoded continuations were used,
  get_param() used to return a 3-tuple of (None, None, string) whereas now it
  will just return the string (since non-encoded continuations don't have
  charset and language parts).

  Also, whereas % values were decoded in all parameter continuations, they are
  now only decoded in encoded parameter parts.

- Bug #1517990: IDLE keybindings on MacOS X now work correctly

- Bug #1517996: IDLE now longer shows the default Tk menu when a
  path browser, class browser or debugger is the frontmost window on MacOS X

- Patch #1520294: Support for getset and member descriptors in types.py,
  inspect.py, and pydoc.py.  Specifically, this allows for querying the type
  of an object against these built-in types and more importantly, for getting
  their docstrings printed in the interactive interpreter's help() function.


Extension Modules
-----------------

- Patch #1519025 and bug #926423: If a KeyboardInterrupt occurs during
  a socket operation on a socket with a timeout, the exception will be
  caught correctly.  Previously, the exception was not caught.

- Patch #1529514: The _ctypes extension is now compiled on more
  openbsd target platforms.

- The ``__reduce__()`` method of the new ``collections.defaultdict`` had
  a memory leak, affecting pickles and deep copies.

- Bug #1471938: Fix curses module build problem on Solaris 8; patch by
  Paul Eggert.

- Patch #1448199: Release interpreter lock in _winreg.ConnectRegistry.

- Patch #1521817: Index range checking on ctypes arrays containing
  exactly one element enabled again.  This allows iterating over these
  arrays, without the need to check the array size before.

- Bug #1521375: When the code in ctypes.util.find_library was
  run with root privileges, it could overwrite or delete
  /dev/null in certain cases; this is now fixed.

- Bug #1467450: On Mac OS X 10.3, RTLD_GLOBAL is now used as the
  default mode for loading shared libraries in ctypes.

- Because of a misspelled preprocessor symbol, ctypes was always
  compiled without thread support; this is now fixed.

- pybsddb Bug #1527939: bsddb module DBEnv dbremove and dbrename
  methods now allow their database parameter to be None as the
  sleepycat API allows.

- Bug #1526460: Fix socketmodule compile on NetBSD as it has a different
  bluetooth API compared with Linux and FreeBSD.

Tests
-----

- Bug #1501330: Change test_ossaudiodev to be much more tolerant in terms of
  how long the test file should take to play.  Now accepts taking 2.93 secs
  (exact time) +/- 10% instead of the hard-coded 3.1 sec.

- Patch #1529686: The standard tests ``test_defaultdict``, ``test_iterlen``,
  ``test_uuid`` and ``test_email_codecs`` didn't actually run any tests when
  run via ``regrtest.py``. Now they do.

Build
-----

- Bug #1439538: Drop usage of test -e in configure as it is not portable.

Mac
---

- PythonLauncher now works correctly when the path to the script contains
  characters that are treated specially by the shell (such as quotes).

- Bug #1527397: PythonLauncher now launches scripts with the working directory
  set to the directory that contains the script instead of the user home
  directory. That latter was an implementation accident and not what users
  expect.


What's New in Python 2.5 beta 2?
================================

*Release date: 11-JUL-2006*

Core and builtins
-----------------

- Bug #1441486: The literal representation of -(sys.maxint - 1)
  again evaluates to a int object, not a long.

- Bug #1501934: The scope of global variables that are locally assigned
  using augmented assignment is now correctly determined.

- Bug #927248: Recursive method-wrapper objects can now safely
  be released.

- Bug #1417699: Reject locale-specific decimal point in float()
  and atof().

- Bug #1511381: codec_getstreamcodec() in codec.c is corrected to
  omit a default "error" argument for NULL pointer.  This allows
  the parser to take a codec from cjkcodecs again.

- Bug #1519018: 'as' is now validated properly in import statements.

- On 64 bit systems, int literals that use less than 64 bits are
  now ints rather than longs.

- Bug #1512814, Fix incorrect lineno's when code at module scope
  started after line 256.

- New function ``sys._current_frames()`` returns a dict mapping thread
  id to topmost thread stack frame.  This is for expert use, and is
  especially useful for debugging application deadlocks.  The functionality
  was previously available in Fazal Majid's ``threadframe`` extension
  module, but it wasn't possible to do this in a wholly threadsafe way from
  an extension.

Library
-------

- Bug #1257728: Mention Cygwin in distutils error message about a missing
  VS 2003.

- Patch #1519566: Update turtle demo, make begin_fill idempotent.

- Bug #1508010: msvccompiler now requires the DISTUTILS_USE_SDK
  environment variable to be set in order to the SDK environment
  for finding the compiler, include files, etc.

- Bug #1515998: Properly generate logical ids for files in bdist_msi.

- warnings.py now ignores ImportWarning by default

- string.Template() now correctly handles tuple-values. Previously,
  multi-value tuples would raise an exception and single-value tuples would
  be treated as the value they contain, instead.

- Bug #822974: Honor timeout in telnetlib.{expect,read_until}
  even if some data are received.

- Bug #1267547: Put proper recursive setup.py call into the
  spec file generated by bdist_rpm.

- Bug #1514693: Update turtle's heading when switching between
  degrees and radians.

- Reimplement turtle.circle using a polyline, to allow correct
  filling of arcs.

- Bug #1514703: Only setup canvas window in turtle when the canvas
  is created.

- Bug #1513223: .close() of a _socketobj now releases the underlying
  socket again, which then gets closed as it becomes unreferenced.

- Bug #1504333: Make sgmllib support angle brackets in quoted
  attribute values.

- Bug #853506: Fix IPv6 address parsing in unquoted attributes in
  sgmllib ('[' and ']' were not accepted).

- Fix a bug in the turtle module's end_fill function.

- Bug #1510580: The 'warnings' module improperly required that a Warning
  category be either a types.ClassType and a subclass of Warning.  The proper
  check is just that it is a subclass with Warning as the documentation states.

- The compiler module now correctly compiles the new try-except-finally
  statement (bug #1509132).

- The wsgiref package is now installed properly on Unix.

- A bug was fixed in logging.config.fileConfig() which caused a crash on
  shutdown when fileConfig() was called multiple times.

- The sqlite3 module did cut off data from the SQLite database at the first
  null character before sending it to a custom converter. This has been fixed
  now.

Extension Modules
-----------------

- #1494314: Fix a regression with high-numbered sockets in 2.4.3. This
  means that select() on sockets > FD_SETSIZE (typically 1024) work again.
  The patch makes sockets use poll() internally where available.

- Assigning None to pointer type fields in ctypes structures possible
  overwrote the wrong fields, this is fixed now.

- Fixed a segfault in _ctypes when ctypes.wintypes were imported
  on non-Windows platforms.

- Bug #1518190: The ctypes.c_void_p constructor now accepts any
  integer or long, without range checking.

- Patch #1517790: It is now possible to use custom objects in the ctypes
  foreign function argtypes sequence as long as they provide a from_param
  method, no longer is it required that the object is a ctypes type.

- The '_ctypes' extension module now works when Python is configured
  with the --without-threads option.

- Bug #1513646: os.access on Windows now correctly determines write
  access, again.

- Bug #1512695: cPickle.loads could crash if it was interrupted with
  a KeyboardInterrupt.

- Bug #1296433: parsing XML with a non-default encoding and
  a CharacterDataHandler could crash the interpreter in pyexpat.

- Patch #1516912: improve Modules support for OpenVMS.

Build
-----

- Automate Windows build process for the Win64 SSL module.

- 'configure' now detects the zlib library the same way as distutils.
  Previously, the slight difference could cause compilation errors of the
  'zlib' module on systems with more than one version of zlib.

- The MSI compileall step was fixed to also support a TARGETDIR
  with spaces in it.

- Bug #1517388: sqlite3.dll is now installed on Windows independent
  of Tcl/Tk.

- Bug #1513032: 'make install' failed on FreeBSD 5.3 due to lib-old
  trying to be installed even though it's empty.

Tests
-----

- Call os.waitpid() at the end of tests that spawn child processes in order
  to minimize resources (zombies).

Documentation
-------------

- Cover ImportWarning, PendingDeprecationWarning and simplefilter() in the
  documentation for the warnings module.

- Patch #1509163: MS Toolkit Compiler no longer available.

- Patch #1504046: Add documentation for xml.etree.


What's New in Python 2.5 beta 1?
================================

*Release date: 20-JUN-2006*

Core and builtins
-----------------

- Patch #1507676: Error messages returned by invalid abstract object operations
  (such as iterating over an integer) have been improved and now include the
  type of the offending object to help with debugging.

- Bug #992017: A classic class that defined a __coerce__() method that returned
  its arguments swapped would infinitely recurse and segfault the interpreter.

- Fix the socket tests so they can be run concurrently.

- Removed 5 integers from C frame objects (PyFrameObject).
  f_nlocals, f_ncells, f_nfreevars, f_stack_size, f_restricted.

- Bug #532646: object.__call__() will continue looking for the __call__
  attribute on objects until one without one is found.  This leads to recursion
  when you take a class and set its __call__ attribute to an instance of the
  class.  Originally fixed for classic classes, but this fix is for new-style.
  Removes the infinite_rec_3 crasher.

- The string and unicode methods startswith() and endswith() now accept
  a tuple of prefixes/suffixes to look for. Implements RFE #1491485.

- Buffer objects, at the C level, never used the char buffer
  implementation even when the char buffer for the wrapped object was
  explicitly requested (originally returned the read or write buffer).
  Now a TypeError is raised if the char buffer is not present but is
  requested.

- Patch #1346214: Statements like "if 0: suite" are now again optimized
  away like they were in Python 2.4.

- Builtin exceptions are now full-blown new-style classes instead of
  instances pretending to be classes, which speeds up exception handling
  by about 80% in comparison to 2.5a2.

- Patch #1494554: Update unicodedata.numeric and unicode.isnumeric to
  Unicode 4.1.

- Patch #921466: sys.path_importer_cache is now used to cache valid and
  invalid file paths for the built-in import machinery which leads to
  fewer open calls on startup.

- Patch #1442927: ``long(str, base)`` is now up to 6x faster for non-power-
  of-2 bases.  The largest speedup is for inputs with about 1000 decimal
  digits.  Conversion from non-power-of-2 bases remains quadratic-time in
  the number of input digits (it was and remains linear-time for bases
  2, 4, 8, 16 and 32).

- Bug #1334662: ``int(string, base)`` could deliver a wrong answer
  when ``base`` was not 2, 4, 8, 10, 16 or 32, and ``string`` represented
  an integer close to ``sys.maxint``.  This was repaired by patch
  #1335972, which also gives a nice speedup.

- Patch #1337051: reduced size of frame objects.

- PyErr_NewException now accepts a tuple of base classes as its
  "base" parameter.

- Patch #876206: function call speedup by retaining allocated frame
  objects.

- Bug #1462152: file() now checks more thoroughly for invalid mode
  strings and removes a possible "U" before passing the mode to the
  C library function.

- Patch #1488312, Fix memory alignment problem on SPARC in unicode

- Bug #1487966: Fix SystemError with conditional expression in assignment

- WindowsError now has two error code attributes: errno, which carries
  the error values from errno.h, and winerror, which carries the error
  values from winerror.h. Previous versions put the winerror.h values
  (from GetLastError()) into the errno attribute.

- Patch #1475845: Raise IndentationError for unexpected indent.

- Patch #1479181: split open() and file() from being aliases for each other.

- Patch #1497053 & bug #1275608: Exceptions occurring in ``__eq__()``
  methods were always silently ignored by dictionaries when comparing keys.
  They are now passed through (except when using the C API function
  ``PyDict_GetItem()``, whose semantics did not change).

- Bug #1456209: In some obscure cases it was possible for a class with a
  custom ``__eq__()`` method to confuse dict internals when class instances
  were used as a dict's keys and the ``__eq__()`` method mutated the dict.
  No, you don't have any code that did this ;-)

Extension Modules
-----------------

- Bug #1295808: expat symbols should be namespaced in pyexpat

- Patch #1462338: Upgrade pyexpat to expat 2.0.0

- Change binascii.hexlify to accept a read-only buffer instead of only a char
  buffer and actually follow its documentation.

- Fixed a potentially invalid memory access of CJKCodecs' shift-jis decoder.

- Patch #1478788 (modified version): The functional extension module has
  been renamed to _functools and a functools Python wrapper module added.
  This provides a home for additional function related utilities that are
  not specifically about functional programming. See PEP 309.

- Patch #1493701: performance enhancements for struct module.

- Patch #1490224: time.altzone is now set correctly on Cygwin.

- Patch #1435422: zlib's compress and decompress objects now have a
  copy() method.

- Patch #1454481: thread stack size is now tunable at runtime for thread
  enabled builds on Windows and systems with Posix threads support.

- On Win32, os.listdir now supports arbitrarily-long Unicode path names
  (up to the system limit of 32K characters).

- Use Win32 API to implement os.{access,chdir,chmod,mkdir,remove,rename,rmdir,utime}.
  As a result, these functions now raise WindowsError instead of OSError.

- ``time.clock()`` on Win64 should use the high-performance Windows
  ``QueryPerformanceCounter()`` now (as was already the case on 32-bit
  Windows platforms).

- Calling Tk_Init twice is refused if the first call failed as that
  may deadlock.

- bsddb: added the DB_ARCH_REMOVE flag and fixed db.DBEnv.log_archive() to
  accept it without potentially using an uninitialized pointer.

- bsddb: added support for the DBEnv.log_stat() and DBEnv.lsn_reset() methods
  assuming BerkeleyDB >= 4.0 and 4.4 respectively.  [pybsddb project SF
  patch numbers 1494885 and 1494902]

- bsddb: added an interface for the BerkeleyDB >= 4.3 DBSequence class.
  [pybsddb project SF patch number 1466734]

- bsddb: fix DBCursor.pget() bug with keyword argument names when no data
  parameter is supplied.  [SF pybsddb bug #1477863]

- bsddb: the __len__ method of a DB object has been fixed to return correct
  results.  It could previously incorrectly return 0 in some cases.
  Fixes SF bug 1493322 (pybsddb bug 1184012).

- bsddb: the bsddb.dbtables Modify method now raises the proper error and
  aborts the db transaction safely when a modifier callback fails.
  Fixes SF python patch/bug #1408584.

- bsddb: multithreaded DB access using the simple bsddb module interface
  now works reliably.  It has been updated to use automatic BerkeleyDB
  deadlock detection and the bsddb.dbutils.DeadlockWrap wrapper to retry
  database calls that would previously deadlock. [SF python bug #775414]

- Patch #1446489: add support for the ZIP64 extensions to zipfile.

- Patch #1506645: add Python wrappers for the curses functions
  is_term_resized, resize_term and resizeterm.

Library
-------

- Patch #815924: Restore ability to pass type= and icon= in tkMessageBox
  functions.

- Patch #812986: Update turtle output even if not tracing.

- Patch #1494750: Destroy master after deleting children in
  Tkinter.BaseWidget.

- Patch #1096231: Add ``default`` argument to Tkinter.Wm.wm_iconbitmap.

- Patch #763580: Add name and value arguments to Tkinter variable
  classes.

- Bug #1117556: SimpleHTTPServer now tries to find and use the system's
  mime.types file for determining MIME types.

- Bug #1339007: Shelf objects now don't raise an exception in their
  __del__ method when initialization failed.

- Patch #1455898: The MBCS codec now supports the incremental mode for
  double-byte encodings.

- ``difflib``'s ``SequenceMatcher.get_matching_blocks()`` was changed to
  guarantee that adjacent triples in the return list always describe
  non-adjacent blocks.  Previously, a pair of matching blocks could end
  up being described by multiple adjacent triples that formed a partition
  of the matching pair.

- Bug #1498146: fix optparse to handle Unicode strings in option help,
  description, and epilog.

- Bug #1366250: minor optparse documentation error.

- Bug #1361643: fix textwrap.dedent() so it handles tabs appropriately;
  clarify docs.

- The wsgiref package has been added to the standard library.

- The functions update_wrapper() and wraps() have been added to the functools
  module. These make it easier to copy relevant metadata from the original
  function when writing wrapper functions.

- The optional ``isprivate`` argument to ``doctest.testmod()``, and the
  ``doctest.is_private()`` function, both deprecated in 2.4, were removed.

- Patch #1359618: Speed up charmap encoder by using a trie structure
  for lookup.

- The functions in the ``pprint`` module now sort dictionaries by key
  before computing the display.  Before 2.5, ``pprint`` sorted a dictionary
  if and only if its display required more than one line, although that
  wasn't documented.  The new behavior increases predictability; e.g.,
  using ``pprint.pprint(a_dict)`` in a doctest is now reliable.

- Patch #1497027: try HTTP digest auth before basic auth in urllib2
  (thanks for J. J. Lee).

- Patch #1496206: improve urllib2 handling of passwords with respect to
  default HTTP and HTTPS ports.

- Patch #1080727: add "encoding" parameter to doctest.DocFileSuite.

- Patch #1281707: speed up gzip.readline.

- Patch #1180296: Two new functions were added to the locale module:
  format_string() to get the effect of  "format % items" but locale-aware,
  and currency() to format a monetary number with currency sign.

- Patch #1486962: Several bugs in the turtle Tk demo module were fixed
  and several features added, such as speed and geometry control.

- Patch #1488881: add support for external file objects in bz2 compressed
  tarfiles.

- Patch #721464: pdb.Pdb instances can now be given explicit stdin and
  stdout arguments, making it possible to redirect input and output
  for remote debugging.

- Patch #1484695: Update the tarfile module to version 0.8. This fixes
  a couple of issues, notably handling of long file names using the
  GNU LONGNAME extension.

- Patch #1478292. ``doctest.register_optionflag(name)`` shouldn't create a
  new flag when ``name`` is already the name of an option flag.

- Bug #1385040: don't allow "def foo(a=1, b): pass" in the compiler
  package.

- Patch #1472854: make the rlcompleter.Completer class usable on non-
  UNIX platforms.

- Patch #1470846: fix urllib2 ProxyBasicAuthHandler.

- Bug #1472827: correctly escape newlines and tabs in attribute values in
  the saxutils.XMLGenerator class.


Build
-----

- Bug #1502728: Correctly link against librt library on HP-UX.

- OpenBSD 3.9 is supported now.

- Patch #1492356: Port to Windows CE.

- Bug/Patch #1481770: Use .so extension for shared libraries on HP-UX for ia64.

- Patch #1471883: Add --enable-universalsdk.

C API
-----

Tests
-----

Tools
-----

Documentation
-------------



What's New in Python 2.5 alpha 2?
=================================

*Release date: 27-APR-2006*

Core and builtins
-----------------

- Bug #1465834: 'bdist_wininst preinstall script support' was fixed
  by converting these apis from macros into exported functions again:

    PyParser_SimpleParseFile PyParser_SimpleParseString PyRun_AnyFile
    PyRun_AnyFileEx PyRun_AnyFileFlags PyRun_File PyRun_FileEx
    PyRun_FileFlags PyRun_InteractiveLoop PyRun_InteractiveOne
    PyRun_SimpleFile PyRun_SimpleFileEx PyRun_SimpleString
    PyRun_String Py_CompileString

- Under COUNT_ALLOCS, types are not necessarily immortal anymore.

- All uses of PyStructSequence_InitType have been changed to initialize
  the type objects only once, even if the interpreter is initialized
  multiple times.

- Bug #1454485, array.array('u') could crash the interpreter.  This was
  due to PyArgs_ParseTuple(args, 'u#', ...) trying to convert buffers (strings)
  to unicode when it didn't make sense.  'u#' now requires a unicode string.

- Py_UNICODE is unsigned.  It was always documented as unsigned, but
  due to a bug had a signed value in previous versions.

- Patch #837242: ``id()`` of any Python object always gives a positive
  number now, which might be a long integer. ``PyLong_FromVoidPtr`` and
  ``PyLong_AsVoidPtr`` have been changed accordingly.  Note that it has
  never been correct to implement a ``__hash()__`` method that returns the
  ``id()`` of an object:

      def __hash__(self):
          return id(self)  # WRONG

  because a hash result must be a (short) Python int but it was always
  possible for ``id()`` to return a Python long.  However, because ``id()``
  could return negative values before, on a 32-bit box an ``id()`` result
  was always usable as a hash value before this patch.  That's no longer
  necessarily so.

- Python on OS X 10.3 and above now uses dlopen() (via dynload_shlib.c)
  to load extension modules and now provides the dl module. As a result,
  sys.setdlopenflags() now works correctly on these systems. (SF patch
  #1454844)

- Patch #1463867: enhanced garbage collection to allow cleanup of cycles
  involving generators that have paused outside of any ``try`` or ``with``
  blocks.  (In 2.5a1, a paused generator that was part of a reference
  cycle could not be garbage collected, regardless of whether it was
  paused in a ``try`` or ``with`` block.)

Extension Modules
-----------------

- Patch #1191065: Fix preprocessor problems on systems where recvfrom
  is a macro.

- Bug #1467952: os.listdir() now correctly raises an error if readdir()
  fails with an error condition.

- Fixed bsddb.db.DBError derived exceptions so they can be unpickled.

- Bug #1117761: bsddb.*open() no longer raises an exception when using
  the cachesize parameter.

- Bug #1149413: bsddb.*open() no longer raises an exception when using
  a temporary db (file=None) with the 'n' flag to truncate on open.

- Bug #1332852: bsddb module minimum BerkeleyDB version raised to 3.3
  as older versions cause excessive test failures.

- Patch #1062014: AF_UNIX sockets under Linux have a special
  abstract namespace that is now fully supported.

Library
-------

- Bug #1223937: subprocess.CalledProcessError reports the exit status
  of the process using the returncode attribute, instead of
  abusing errno.

- Patch #1475231: ``doctest`` has a new ``SKIP`` option, which causes
  a doctest to be skipped (the code is not run, and the expected output
  or exception is ignored).

- Fixed contextlib.nested to cope with exceptions being raised and
  caught inside exit handlers.

- Updated optparse module to Optik 1.5.1 (allow numeric constants in
  hex, octal, or binary; add ``append_const`` action; keep going if
  gettext cannot be imported; added ``OptionParser.destroy()`` method;
  added ``epilog`` for better help generation).

- Bug #1473760: ``tempfile.TemporaryFile()`` could hang on Windows, when
  called from a thread spawned as a side effect of importing a module.

- The pydoc module now supports documenting packages contained in
  .zip or .egg files.

- The pkgutil module now has several new utility functions, such
  as ``walk_packages()`` to support working with packages that are either
  in the filesystem or zip files.

- The mailbox module can now modify and delete messages from
  mailboxes, in addition to simply reading them.  Thanks to Gregory
  K. Johnson for writing the code, and to the 2005 Google Summer of
  Code for funding his work.

- The ``__del__`` method of class ``local`` in module ``_threading_local``
  returned before accomplishing any of its intended cleanup.

- Patch #790710: Add breakpoint command lists in pdb.

- Patch #1063914: Add Tkinter.Misc.clipboard_get().

- Patch #1191700: Adjust column alignment in bdb breakpoint lists.

- SimpleXMLRPCServer relied on the fcntl module, which is unavailable on
  Windows. Bug #1469163.

- The warnings, linecache, inspect, traceback, site, and doctest modules
  were updated to work correctly with modules imported from zipfiles or
  via other PEP 302 __loader__ objects.

- Patch #1467770: Reduce usage of subprocess._active to processes which
  the application hasn't waited on.

- Patch #1462222: Fix Tix.Grid.

- Fix exception when doing glob.glob('anything*/')

- The pstats.Stats class accepts an optional stream keyword argument to
  direct output to an alternate file-like object.

Build
-----

- The Makefile now has a reindent target, which runs reindent.py on
  the library.

- Patch #1470875: Building Python with MS Free Compiler

- Patch #1161914: Add a python-config script.

- Patch #1324762:Remove ccpython.cc; replace --with-cxx with
  --with-cxx-main. Link with C++ compiler only if --with-cxx-main was
  specified. (Can be overridden by explicitly setting LINKCC.) Decouple
  CXX from --with-cxx-main, see description in README.

- Patch #1429775: Link extension modules with the shared libpython.

- Fixed a libffi build problem on MIPS systems.

- ``PyString_FromFormat``, ``PyErr_Format``, and ``PyString_FromFormatV``
  now accept formats "%u" for unsigned ints, "%lu" for unsigned longs,
  and "%zu" for unsigned integers of type ``size_t``.

Tests
-----

- test_contextlib now checks contextlib.nested can cope with exceptions
  being raised and caught inside exit handlers.

- test_cmd_line now checks operation of the -m and -c command switches

- The test_contextlib test in 2.5a1 wasn't actually run unless you ran
  it separately and by hand.  It also wasn't cleaning up its changes to
  the current Decimal context.

- regrtest.py now has a -M option to run tests that test the new limits of
  containers, on 64-bit architectures. Running these tests is only sensible
  on 64-bit machines with more than two gigabytes of memory. The argument
  passed is the maximum amount of memory for the tests to use.

Tools
-----

- Added the Python benchmark suite pybench to the Tools/ directory;
  contributed by Marc-Andre Lemburg.

Documentation
-------------

- Patch #1473132: Improve docs for ``tp_clear`` and ``tp_traverse``.

- PEP 343: Added Context Types section to the library reference
  and attempted to bring other PEP 343 related documentation into
  line with the implementation and/or python-dev discussions.

- Bug #1337990: clarified that ``doctest`` does not support examples
  requiring both expected output and an exception.


What's New in Python 2.5 alpha 1?
=================================

*Release date: 05-APR-2006*

Core and builtins
-----------------

- PEP 338: -m command line switch now delegates to runpy.run_module
  allowing it to support modules in packages and zipfiles

- On Windows, .DLL is not an accepted file name extension for
  extension modules anymore; extensions are only found if they
  end in .PYD.

- Bug #1421664: sys.stderr.encoding is now set to the same value as
  sys.stdout.encoding.

- __import__ accepts keyword arguments.

- Patch #1460496: round() now accepts keyword arguments.

- Fixed bug #1459029 - unicode reprs were double-escaped.

- Patch #1396919: The system scope threads are reenabled on FreeBSD
  5.4 and later versions.

- Bug #1115379: Compiling a Unicode string with an encoding declaration
  now gives a SyntaxError.

- Previously, Python code had no easy way to access the contents of a
  cell object. Now, a ``cell_contents`` attribute has been added
  (closes patch #1170323).

- Patch #1123430: Python's small-object allocator now returns an arena to
  the system ``free()`` when all memory within an arena becomes unused
  again.  Prior to Python 2.5, arenas (256KB chunks of memory) were never
  freed.  Some applications will see a drop in virtual memory size now,
  especially long-running applications that, from time to time, temporarily
  use a large number of small objects.  Note that when Python returns an
  arena to the platform C's ``free()``, there's no guarantee that the
  platform C library will in turn return that memory to the operating system.
  The effect of the patch is to stop making that impossible, and in tests it
  appears to be effective at least on Microsoft C and gcc-based systems.
  Thanks to Evan Jones for hard work and patience.

- Patch #1434038: property() now uses the getter's docstring if there is
  no "doc" argument given. This makes it possible to legitimately use
  property() as a decorator to produce a read-only property.

- PEP 357, patch 1436368: add an __index__ method to int/long and a matching
  nb_index slot to the PyNumberMethods struct.  The slot is consulted instead
  of requiring an int or long in slicing and a few other contexts, enabling
  other objects (e.g. Numeric Python's integers) to be used as slice indices.

- Fixed various bugs reported by Coverity's Prevent tool.

- PEP 352, patch #1104669: Make exceptions new-style objects.  Introduced the
  new exception base class, BaseException, which has a new message attribute.
  KeyboardInterrupt and SystemExit to directly inherit from BaseException now.
  Raising a string exception now raises a DeprecationWarning.

- Patch #1438387, PEP 328: relative and absolute imports. Imports can now be
  explicitly relative, using 'from .module import name' to mean 'from the same
  package as this module is in. Imports without dots still default to the
  old relative-then-absolute, unless 'from __future__ import
  absolute_import' is used.

- Properly check if 'warnings' raises an exception (usually when a filter set
  to "error" is triggered) when raising a warning for raising string
  exceptions.

- CO_GENERATOR_ALLOWED is no longer defined. This behavior is the default.
  The name was removed from Include/code.h.

- PEP 308: conditional expressions were added: (x if cond else y).

- Patch 1433928:
  - The copy module now "copies" function objects (as atomic objects).
  - dict.__getitem__ now looks for a __missing__ hook before raising
    KeyError.

- PEP 343: with statement implemented. Needs ``from __future__ import
  with_statement``. Use of 'with' as a variable will generate a warning.
  Use of 'as' as a variable will also generate a warning (unless it's
  part of an import statement).
  The following objects have __context__ methods:
  - The built-in file type.
  - The thread.LockType type.
  - The following types defined by the threading module:
    Lock, RLock, Condition, Semaphore, BoundedSemaphore.
  - The decimal.Context class.

- Fix the encodings package codec search function to only search
  inside its own package. Fixes problem reported in patch #1433198.

  Note: Codec packages should implement and register their own
  codec search function. PEP 100 has the details.

- PEP 353: Using ``Py_ssize_t`` as the index type.

- ``PYMALLOC_DEBUG`` builds now add ``4*sizeof(size_t)`` bytes of debugging
  info to each allocated block, since the ``Py_ssize_t`` changes (PEP 353)
  now allow Python to make use of memory blocks exceeding 2**32 bytes for
  some purposes on 64-bit boxes.  A ``PYMALLOC_DEBUG`` build was limited
  to 4-byte allocations before.

- Patch #1400181, fix unicode string formatting to not use the locale.
  This is how string objects work.  u'%f' could use , instead of .
  for the decimal point.  Now both strings and unicode always use periods.

- Bug #1244610, #1392915, fix build problem on OpenBSD 3.7 and 3.8.
  configure would break checking curses.h.

- Bug #959576: The pwd module is now builtin. This allows Python to be
  built on UNIX platforms without $HOME set.

- Bug #1072182, fix some potential problems if characters are signed.

- Bug #889500, fix line number on SyntaxWarning for global declarations.

- Bug #1378022, UTF-8 files with a leading BOM crashed the interpreter.

- Support for converting hex strings to floats no longer works.
  This was not portable.  float('0x3') now raises a ValueError.

- Patch #1382163: Expose Subversion revision number to Python.  New C API
  function Py_GetBuildNumber().  New attribute sys.subversion.  Build number
  is now displayed in interactive prompt banner.

- Implementation of PEP 341 - Unification of try/except and try/finally.
  "except" clauses can now be written together with a "finally" clause in
  one try statement instead of two nested ones.  Patch #1355913.

- Bug #1379994: Builtin unicode_escape and raw_unicode_escape codec
  now encodes backslash correctly.

- Patch #1350409: Work around signal handling bug in Visual Studio 2005.

- Bug #1281408: Py_BuildValue now works correctly even with unsigned longs
  and long longs.

- SF Bug #1350188, "setdlopenflags" leads to crash upon "import"
  It was possible for dlerror() to return a NULL pointer, so
  it will now use a default error message in this case.

- Replaced most Unicode charmap codecs with new ones using the
  new Unicode translate string feature in the builtin charmap
  codec; the codecs were created from the mapping tables available
  at ftp.unicode.org and contain a few updates (e.g. the Mac OS
  encodings now include a mapping for the Apple logo)

- Added a few more codecs for Mac OS encodings

- Sped up some Unicode operations.

- A new AST parser implementation was completed. The abstract
  syntax tree is available for read-only (non-compile) access
  to Python code; an _ast module was added.

- SF bug #1167751: fix incorrect code being produced for generator expressions.
  The following code now raises a SyntaxError:  foo(a = i for i in range(10))

- SF Bug #976608: fix SystemError when mtime of an imported file is -1.

- SF Bug #887946: fix segfault when redirecting stdin from a directory.
  Provide a warning when a directory is passed on the command line.

- Fix segfault with invalid coding.

- SF bug #772896: unknown encoding results in MemoryError.

- All iterators now have a Boolean value of True.  Formerly, some iterators
  supported a __len__() method which evaluated to False when the iterator
  was empty.

- On 64-bit platforms, when __len__() returns a value that cannot be
  represented as a C int, raise OverflowError.

- test__locale is skipped on OS X < 10.4 (only partial locale support is
  present).

- 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.

- The implementation of set() and frozenset() was revised to use its
  own internal data structure.  Memory consumption is reduced by 1/3
  and there are modest speed-ups as well.  The API is unchanged.

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

- SF bug #1229429: PyObject_CallMethod failed to decrement some
  reference counts in some error exit cases.

- 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 there's 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.

- SF bug #1232517: An overflow error was not detected properly when
  attempting to convert a large float to an int in os.utime().

- SF bug #1224347: hex longs now print with lowercase letters just
  like their int counterparts.

- 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).

- SF patch #1180995: marshal now uses a binary format by default when
  serializing floats.

- SF patch #1181301: on platforms that appear to use IEEE 754 floats,
  the routines that promise to produce IEEE 754 binary representations
  of floats now simply copy bytes around.

- bug #967182: disallow opening files with 'wU' or 'aU' as specified by PEP
  278.

- patch #1109424: int, long, float, complex, and unicode now check for the
  proper magic slot for type conversions when subclassed.  Previously the
  magic slot was ignored during conversion.  Semantics now match the way
  subclasses of str always behaved.  int/long/float, conversion of an instance
  to the base class has been moved to the proper nb_* magic slot and out of
  PyNumber_*().
  Thanks Walter D�rwald.

- Descriptors defined in C with a PyGetSetDef structure, where the setter is
  NULL, now raise an AttributeError when attempting to set or delete the
  attribute.  Previously a TypeError was raised, but this was inconsistent
  with the equivalent pure-Python implementation.

- 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.

- Move exception finalisation later in the shutdown process - this
  fixes the crash seen in bug #1165761

- Added two new builtins, any() and all().

- Defining a class with empty parentheses is now allowed
  (e.g., ``class C(): pass`` is no longer a syntax error).
  Patch #1176012 added support to the 'parser' module and 'compiler' package
  (thanks to logistix for that added support).

- Patch #1115086: Support PY_LONGLONG in structmember.

- Bug #115…