Mailman 3 May 2012 - Python-Dev

Accepting PEP 3144 (the ipaddress library)
by Nick Coghlan May 15, 2012

May 15, 2012

Based on the current version of PEP 3144 and its reference implementation, I am formally accepting ipaddress into the standard library. I believe Peter has satisfactorily resolved the concerns previously raised with the proposed API, and if I missed anything... well, that's why we have alpha releases and the new provisional API status :) There's one point that could do with better documentation, which is the meaning of a "non-strict" Network address. In ipaddr.py, non-strict networks filled the role now filled by the separate Interface objects in the ipaddress module. In ipaddress, the "strict" flag instead just selects between raising a ValueError when passed a host address (the default) or simply coercing the host address to the appropriate network address. That behaviour strikes me as both reasonable and useful - the coercion aspect just needs to be mentioned in the documentation. The integration of the module into 3.3. will be tracked in http://bugs.python.org/issue14814 Peter will also need to be granted commit access in order to maintain the module. Regards, Nick. -- Nick Coghlan | ncoghlan(a)gmail.com | Brisbane, Australia

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Accepting PEP 415 (alternative implementation strategy for PEP 409's "raise exc from None" syntax)
by Nick Coghlan May 15, 2012

May 15, 2012

As the subject line says, as Guido's delegate, I'm accepting Benjamin's PEP 415 with the current reference implementation. This PEP changes the implementation of the new "raise exc from None" syntax to eliminate the use of Ellipsis as a "not set" sentinel value in favour of a separate "__suppress_context__" attribute on exceptions. This new flag defaults to False, but is implicitly set to True whenever a value is assigned to __cause__ (regardless of whether that happens via direct assignment , the new syntax or the C API). The question of how the builtin and standard library exception display routines should handle the cause where both __cause__ and __context__ are set and __suppress_context__ has been explicitly set to False will be decided independently of the PEP acceptance (see http://bugs.python.org/issue14805). Regards, Nick. -- Nick Coghlan | ncoghlan(a)gmail.com | Brisbane, Australia

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Re: [Python-Dev] cpython: Issue #14532: Add a secure_compare() helper to the hmac module, to mitigate
by Antoine Pitrou May 14, 2012

May 14, 2012

On Sun, 13 May 2012 19:53:27 +0200 charles-francois.natali <python-checkins(a)python.org> wrote: > > +This module also provides the following helper function: > + > +.. function:: secure_compare(a, b) [...] You need a versionadded tag. Regards Antoine.

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Preparation for VS2010 - MSDN for Windows build slaves, core devs
by Brian Curtin May 13, 2012

May 13, 2012

Hi all, If you are a running a build slave or otherwise have an MSDN account for development work, please check that your MSDN subscription is still in effect. If the subscription expired, please let me know in private what your subscriber ID is along with the email address you use for the account. Eventually we're switching to VS2010 so each slave will need to have that version of the compiler installed. Thanks

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Re: [Python-Dev] [Python-checkins] cpython: Issue #14779: Do not use get_config_var('SIZEOF_VOID_P') on OS X 64-/32-bit
by "Martin v. Löwis" May 13, 2012

May 13, 2012

> - self.sizeof_void_p = get_config_var('SIZEOF_VOID_P') > + self.sizeof_void_p = get_config_var('SIZEOF_VOID_P') \ > + if sys.platform != 'darwin' else None > if not self.sizeof_void_p: > - self.sizeof_void_p = 8 if architecture()[0] == '64bit' else 4 > + self.sizeof_void_p = 8 if sys.maxsize> 2**32 else 4 > Why not unconditionally use sys.maxsize? I'd also hard-code that sys.maxsize ought to be either 2**31-1 or 2**63-1. Regards, Martin

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WSGI paranoia with stdout/stderr
by anatoly techtonik May 13, 2012

May 13, 2012

There is fear and uncertainty in this pull request to PyPI - https://bitbucket.org/techtonik/pypi-techtonik/changeset/5396f8c60d49#comme… - which is about that writing to stderr _might_ break things in WSGI applications. As a consequence logging to console will not be accepted in debug mode, which is disappointing, but not as disappointing as the absence of proper explanation. Martin couldn't provide any grounds for his fears, so I am asking fellow Python developers if anybody remember "if writing to stderr can break things in generic WSGI application" and reassure Martin that everything will be ok. -- anatoly t.

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Exception and ABCs / issue #12029
by George-Cristian Bîrzan May 11, 2012

May 11, 2012

As per http://bugs.python.org/issue12029 , ABC registration cannot be used for exceptions. This was introduced in a commit that fixed a recursion limit problem back in 2008 (http://hg.python.org/cpython/rev/d6e86a96f9b3/#l8.10). This was later fixed in a different way and improved upon in the 2.x branch in http://hg.python.org/cpython/rev/7e86fa255fc2 and http://hg.python.org/cpython/rev/57de1ad15c54 respectively. Applying the fix from the 2.x branch for doesn't make any tests fail, and it fixes the problem described in the bug report. There are, however, two questions about this: * Is this a feature, or a bug? I would say that it's a bug, but even if it's not, it has to be documented, since one generally assumes that it will work. * Even so, is it worth fixing, considering the limited use cases for it? This slows exception type checking 3 times. I added a new test to pybench: before: TryRaiseExceptClass: 25ms 25ms 0.39us 0.216ms after: TryRaiseExceptException: 31ms 31ms 0.48us 0.214ms However, that doesn't tell the whole story, since there's overhead from raising the exception. In order to find out how much actually checking slows down the checking, I ran three timeits, with the following code: 1) try: raise ValueError() except NameError: pass except NameError: pass except ValueError: pass 2) try: raise ValueError() except NameError: pass except ValueError: pass 3) try: raise ValueError() except ValueError: pass Times are in ms: before after 1 528.69 825.38 2 473.73 653.39 3 416.29 496.80 avgdiff 56.23 164.29 The numbers don't change significantly for more exception tests. -- George-Cristian Bîrzan

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Summary of Python tracker Issues
by Python tracker May 11, 2012

May 11, 2012

ACTIVITY SUMMARY (2012-05-04 - 2012-05-11) Python tracker at http://bugs.python.org/ To view or respond to any of the issues listed below, click on the issue. Do NOT respond to this message. Issues counts and deltas: open 3418 (+19) closed 23143 (+42) total 26561 (+61) Open issues with patches: 1460 Issues opened (38) ================== #13815: tarfile.ExFileObject can't be wrapped using io.TextIOWrapper http://bugs.python.org/issue13815 reopened by r.david.murray #14724: kill imp.load_dynamic's third argument http://bugs.python.org/issue14724 opened by pitrou #14728: trace function not set, causing some Pdb commands to fail http://bugs.python.org/issue14728 opened by xdegaye #14730: Implementation of the PEP 419: Protecting cleanup statements f http://bugs.python.org/issue14730 opened by tailhook #14731: Enhance Policy framework in preparation for adding email6 poli http://bugs.python.org/issue14731 opened by r.david.murray #14732: PEP 3121 Refactoring applied to _csv module http://bugs.python.org/issue14732 opened by Robin.Schreiber #14733: Custom commands don't work http://bugs.python.org/issue14733 opened by LEW21 #14734: Use binascii.b2a_qp/a2b_qp in email package header handling? http://bugs.python.org/issue14734 opened by r.david.murray #14735: Version 3.2.3 IDLE CTRL-Z plus Carriage Return to end does not http://bugs.python.org/issue14735 opened by ewodrich #14739: Add PyArg_Parse format unit like O& but providing context http://bugs.python.org/issue14739 opened by larry #14742: test_tools very slow http://bugs.python.org/issue14742 opened by pitrou #14743: on terminating, Pdb debugs itself http://bugs.python.org/issue14743 opened by xdegaye #14744: Use _PyUnicodeWriter API in str.format() internals http://bugs.python.org/issue14744 opened by haypo #14747: Classifiers are missing from distutils2-generated metadata http://bugs.python.org/issue14747 opened by agronholm #14748: spwd.getspall() is returning LDAP (non local) users too http://bugs.python.org/issue14748 opened by halfie #14750: Tkinter application doesn't run from source build on Windows http://bugs.python.org/issue14750 opened by vinay.sajip #14751: Pdb does not stop at a breakpoint http://bugs.python.org/issue14751 opened by xdegaye #14755: Distutils2 doesn't have a Python 3 version on PyPI http://bugs.python.org/issue14755 opened by njwilson #14757: INCA: Inline Caching meets Quickening in Python 3.3 http://bugs.python.org/issue14757 opened by sbrunthaler #14758: SMTPServer of smptd does not support binding to an IPv6 addres http://bugs.python.org/issue14758 opened by vsergeev #14759: BSDDB license missing from liscense page in 2.7. http://bugs.python.org/issue14759 opened by Jeff.Laing #14766: Non-naive time comparison throws naive time error http://bugs.python.org/issue14766 opened by Chris.Bergstresser #14767: urllib.request.HTTPRedirectHandler raises HTTPError when Locat http://bugs.python.org/issue14767 opened by jspenguin #14769: Add test to automatically detect missing format units in skipi http://bugs.python.org/issue14769 opened by larry #14770: Minor documentation fixes http://bugs.python.org/issue14770 opened by michael.foord #14771: Occasional failure in test_ioctl http://bugs.python.org/issue14771 opened by pitrou #14772: Return destination values in some shutil functions http://bugs.python.org/issue14772 opened by brian.curtin #14773: fwalk breaks on dangling symlinks http://bugs.python.org/issue14773 opened by hynek #14774: _sysconfigdata.py doesn't support multiple build configuration http://bugs.python.org/issue14774 opened by dmalcolm #14775: Slow unpickling of certain dictionaries in python 2.7 vs pytho http://bugs.python.org/issue14775 opened by stw #14776: Add SystemTap static markers http://bugs.python.org/issue14776 opened by dmalcolm #14777: Tkinter clipboard_get() decodes characters incorrectly http://bugs.python.org/issue14777 opened by takluyver #14778: IrrationalVersionError should include the project name http://bugs.python.org/issue14778 opened by njwilson #14779: test_buffer fails on OS X universal 64-/32-bit builds http://bugs.python.org/issue14779 opened by ned.deily #14780: SSL should use OpenSSL-defined default certificate store if ca http://bugs.python.org/issue14780 opened by jfunk #14781: Default to year 1 in strptime if year 0 has been specified http://bugs.python.org/issue14781 opened by Matthias.Meyer #14782: Tabcompletion of classes with static methods and __call__ has http://bugs.python.org/issue14782 opened by wpettersson #14783: Update int() docstring from manual http://bugs.python.org/issue14783 opened by terry.reedy Most recent 15 issues with no replies (15) ========================================== #14783: Update int() docstring from manual http://bugs.python.org/issue14783 #14782: Tabcompletion of classes with static methods and __call__ has http://bugs.python.org/issue14782 #14773: fwalk breaks on dangling symlinks http://bugs.python.org/issue14773 #14771: Occasional failure in test_ioctl http://bugs.python.org/issue14771 #14751: Pdb does not stop at a breakpoint http://bugs.python.org/issue14751 #14747: Classifiers are missing from distutils2-generated metadata http://bugs.python.org/issue14747 #14734: Use binascii.b2a_qp/a2b_qp in email package header handling? http://bugs.python.org/issue14734 #14731: Enhance Policy framework in preparation for adding email6 poli http://bugs.python.org/issue14731 #14730: Implementation of the PEP 419: Protecting cleanup statements f http://bugs.python.org/issue14730 #14714: PEp 414 tokenizing hook does not preserve tabs http://bugs.python.org/issue14714 #14713: PEP 414 installation hook fails with an AssertionError http://bugs.python.org/issue14713 #14712: Integrate PEP 405 http://bugs.python.org/issue14712 #14709: http.client fails sending read()able Object http://bugs.python.org/issue14709 #14703: Update PEP metaprocesses to describe PEP czar role http://bugs.python.org/issue14703 #14689: make PYTHONWARNINGS variable work in libpython http://bugs.python.org/issue14689 Most recent 15 issues waiting for review (15) ============================================= #14780: SSL should use OpenSSL-defined default certificate store if ca http://bugs.python.org/issue14780 #14779: test_buffer fails on OS X universal 64-/32-bit builds http://bugs.python.org/issue14779 #14776: Add SystemTap static markers http://bugs.python.org/issue14776 #14773: fwalk breaks on dangling symlinks http://bugs.python.org/issue14773 #14772: Return destination values in some shutil functions http://bugs.python.org/issue14772 #14770: Minor documentation fixes http://bugs.python.org/issue14770 #14769: Add test to automatically detect missing format units in skipi http://bugs.python.org/issue14769 #14766: Non-naive time comparison throws naive time error http://bugs.python.org/issue14766 #14757: INCA: Inline Caching meets Quickening in Python 3.3 http://bugs.python.org/issue14757 #14751: Pdb does not stop at a breakpoint http://bugs.python.org/issue14751 #14750: Tkinter application doesn't run from source build on Windows http://bugs.python.org/issue14750 #14744: Use _PyUnicodeWriter API in str.format() internals http://bugs.python.org/issue14744 #14743: on terminating, Pdb debugs itself http://bugs.python.org/issue14743 #14735: Version 3.2.3 IDLE CTRL-Z plus Carriage Return to end does not http://bugs.python.org/issue14735 #14733: Custom commands don't work http://bugs.python.org/issue14733 Top 10 most discussed issues (10) ================================= #14657: Avoid two importlib copies http://bugs.python.org/issue14657 18 msgs #13815: tarfile.ExFileObject can't be wrapped using io.TextIOWrapper http://bugs.python.org/issue13815 13 msgs #9260: A finer grained import lock http://bugs.python.org/issue9260 10 msgs #14744: Use _PyUnicodeWriter API in str.format() internals http://bugs.python.org/issue14744 10 msgs #14759: BSDDB license missing from liscense page in 2.7. http://bugs.python.org/issue14759 9 msgs #14082: shutil doesn't copy extended attributes http://bugs.python.org/issue14082 7 msgs #14702: os.makedirs breaks under autofs directories http://bugs.python.org/issue14702 7 msgs #14766: Non-naive time comparison throws naive time error http://bugs.python.org/issue14766 7 msgs #14772: Return destination values in some shutil functions http://bugs.python.org/issue14772 7 msgs #14750: Tkinter application doesn't run from source build on Windows http://bugs.python.org/issue14750 6 msgs Issues closed (39) ================== #2377: Replace __import__ w/ importlib.__import__ http://bugs.python.org/issue2377 closed by brett.cannon #13989: gzip always returns byte strings, no text mode http://bugs.python.org/issue13989 closed by python-dev #14034: Add argparse howto http://bugs.python.org/issue14034 closed by ezio.melotti #14093: Mercurial version information not appearing in Windows builds http://bugs.python.org/issue14093 closed by python-dev #14157: time.strptime without a year fails on Feb 29 http://bugs.python.org/issue14157 closed by pitrou #14583: try/except import fails --without-threads http://bugs.python.org/issue14583 closed by pitrou #14654: Faster utf-8 decoding http://bugs.python.org/issue14654 closed by loewis #14662: shutil.move doesn't handle ENOTSUP raised by chflags on OS X http://bugs.python.org/issue14662 closed by ned.deily #14695: Tools/parser/unparse.py is out of date. http://bugs.python.org/issue14695 closed by mark.dickinson #14697: parser module doesn't support set displays or set comprehensio http://bugs.python.org/issue14697 closed by mark.dickinson #14700: Integer overflow in classic string formatting http://bugs.python.org/issue14700 closed by mark.dickinson #14701: parser module doesn't support 'raise ... from' http://bugs.python.org/issue14701 closed by mark.dickinson #14705: Add 'bool' format character to PyArg_ParseTuple* http://bugs.python.org/issue14705 closed by larry #14716: Use unicode_writer API for str.format() http://bugs.python.org/issue14716 closed by python-dev #14722: Overflow in parsing 'float' parameters in PyArg_ParseTuple* http://bugs.python.org/issue14722 closed by mark.dickinson #14723: Misleading error message for str.format() http://bugs.python.org/issue14723 closed by eric.smith #14725: test_multiprocessing failure under Windows http://bugs.python.org/issue14725 closed by sbt #14726: Lib/email/*.py use an EMPTYSTRING global instead of '' http://bugs.python.org/issue14726 closed by r.david.murray #14727: test_multiprocessing failure under Linux http://bugs.python.org/issue14727 closed by vinay.sajip #14729: test_faulthandler test is too specific to work on Windows http://bugs.python.org/issue14729 closed by python-dev #14736: Add {encode, decode}_filter_properties() functions to lzma mod http://bugs.python.org/issue14736 closed by nadeem.vawda #14737: subprocess.Popen pipes not working http://bugs.python.org/issue14737 closed by pitrou #14738: Amazingly faster UTF-8 decoding http://bugs.python.org/issue14738 closed by pitrou #14740: get_payload(n, True) returns None http://bugs.python.org/issue14740 closed by r.david.murray #14741: parser module doesn't support Ellipsis. http://bugs.python.org/issue14741 closed by mark.dickinson #14745: Misleading exception http://bugs.python.org/issue14745 closed by python-dev #14746: Remove redundant paragraphs from getargs.c skipitem() http://bugs.python.org/issue14746 closed by larry #14749: Add 'Z' to skipitem() in Python/getargs.c http://bugs.python.org/issue14749 closed by larry #14752: Memleak in typeobject add_methods() http://bugs.python.org/issue14752 closed by python-dev #14753: multiprocessing treats negative timeouts differently from befo http://bugs.python.org/issue14753 closed by sbt #14754: Emacs configuration to enforce PEP7 http://bugs.python.org/issue14754 closed by georg.brandl #14756: Empty Dict in Initializer is Shared Betwean Objects http://bugs.python.org/issue14756 closed by pitrou #14760: logging: make setLevel() return handler itself for chained con http://bugs.python.org/issue14760 closed by vinay.sajip #14761: Memleak in import.c load_source_module() http://bugs.python.org/issue14761 closed by pitrou #14762: ElementTree memory leak http://bugs.python.org/issue14762 closed by Giuseppe.Attardi #14763: string.split maxsplit documented incorrectly http://bugs.python.org/issue14763 closed by ezio.melotti #14764: importlib.test.benchmark broken http://bugs.python.org/issue14764 closed by brett.cannon #14765: the struct example should give consistent results across diffe http://bugs.python.org/issue14765 closed by meador.inge #14768: os.path.expanduser('~/a') doesn't works correctly when HOME is http://bugs.python.org/issue14768 closed by python-dev

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Adding types.build_class for 3.3
by Nick Coghlan May 11, 2012

May 11, 2012

A while back I pointed out that there's no easy PEP 3115 compliant way to dynamically create a class (finding the right metaclass, calling __prepare__, etc). I initially proposed providing this as operator.build_class, and Daniel Urban created a patch that implements that API (http://bugs.python.org/issue14588). However, in starting to write the documentation for the new API, I realised that the operator module really isn't the right home for the functionality. Instead, I'm now thinking we should add a _types C extension module and expose the new function as types.build_class(). I don't want to add an entire new module just for this feature, and the types module seems like an appropriate home for it. Thoughts? Regards, Nick. -- Nick Coghlan | ncoghlan(a)gmail.com | Brisbane, Australia

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Allow use of sphinx-autodoc in the standard library documentation?
by Nick Coghlan May 10, 2012

May 10, 2012

One of the requirements for acceptance of PEP 3144 if the provision of a reStructuredText API reference. The current plan for dealing with that is to use Spinx apidoc to create a skeleton, and then capture the rewritten ReST produced by autodoc. However, it occurs to me that the module reference could actually *use* autodoc, with additional prose added to supplement the docstrings, rather than completely replacing them. I'd initially dismissed this idea out of hand, but recently realised I didn't have any especially strong arguments against it (and there are all the usual "avoid double-keying data" arguments in favour). So, given the advantages of autodoc, is there a concrete reason why we can't use it for the documentation of *new* standard library modules? Regards, Nick. -- Nick Coghlan | ncoghlan(a)gmail.com | Brisbane, Australia

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