Mailman 3 March 2015 - Python-Dev

Sporadic failures of test_subprocess and test_multiprocessing_spawn
by Victor Stinner 30 Mar '15

30 Mar '15

Hi, Can you please take a look at the following issue and try to reproduce it? http://bugs.python.org/issue23771 The following tests sometimes hang on "x86 Ubuntu Shared 3.x" and "AMD64 Debian root 3.x" buildbots: - test_notify_all() of test_multiprocessing_spawn - test_double_close_on_error() of test_subprocess - other sporadic failures of test_subprocess I'm quite sure that they are regressions, maybe related to the implementation of the PEP 475. In the middle of all PEP 475 changes, I changed some functions to release the GIL on I/O, it wasn't the case before. I may be related. Are you able to reproduce these issues? I'm unable to reproduce them on Fedora 21. Maybe they are more likely on Debian-like operating systems? Victor

3 7

Builtin functions are magically static methods?
by Paul Sokolovsky 29 Mar '15

29 Mar '15

Hello, I looked into porting Python3 codecs module to MicroPython and saw rather strange behavior, which is best illustrated with following testcase: ========== def foo(a): print("func:", a) import _codecs fun = _codecs.utf_8_encode #fun = hash #fun = str.upper #fun = foo class Bar: meth = fun print(fun) print(fun("foo")) b = Bar() print(b.meth("bar")) ========== Uncommenting either _codecs.utf_8_encode or hash (both builtin functions) produces 2 similar output lines, which in particular means that its possible to call a native function as (normal) object method, which then behaves as if it was a staticmethod - self is not passed to a native function. Using native object method in this manner produces error of self type mismatch (TypeError: descriptor 'upper' for 'str' objects doesn't apply to 'Bar' object). And using standard Python function expectedly produces error about argument number mismatch, because used as a method, function gets extra self argument. So the questions are: 1. How so, the native functions exhibit such magic behavior? Is it documented somewhere - I never read or heard about that (cannot say I read each and every word in Python reference docs, but read enough. As an example, https://docs.python.org/3/library/stdtypes.html#functions is rather short and mentions difference in implementation, not in meta-behavior). 2. The main question: how to easily and cleanly achieve the same behavior for standard Python functions? I'd think it's staticmethod(), but: >>> staticmethod(lambda:1)() Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: 'staticmethod' object is not callable Surprise. (By "easily and cleanly" I mean without meta-programming tricks, like instead of real arguments accept "*args, **kwargs" and then munge args). Thanks, Paul mailto:pmiscml@gmail.com

2 1

Buildbot x86 XP-4 3.x doesn't compile anymore: drop it?
by Victor Stinner 29 Mar '15

29 Mar '15

Hi, The buildbot x86 XP-4 3.x doesn't compile anymore since 3 months or more (maybe when Steve upgraded the Visual Studio project to VS 2015? I don't know). Would it be possible to fix this buildbot, or to turn it off? By the way, do we seriously want to support Windows XP? I mean, *who* will maintain it (no me sorry!). I saw recent changes to explicitly *drop* support for Windows older than Visa (stop using GetTickCount, always call GetTickCount64, for time.monotonic). Victor

4 5

Buildbot PPC64 AIX 3.x failures
by Victor Stinner 28 Mar '15

28 Mar '15

Hi, There are many failures on the AIX buildbot. Can someone try to fix them? Or would it be possible to turn off the buildbot to quickly see regressions? http://buildbot.python.org/all/builders/PPC64%20AIX%203.x/builds/3426/steps… The buildbot has not enough memory, and some tests are failing since more than 3 months. Victor

2 1

Summary of Python tracker Issues
by Python tracker 27 Mar '15

27 Mar '15

ACTIVITY SUMMARY (2015-03-20 - 2015-03-27) 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 4820 (+22) closed 30732 (+47) total 35552 (+69) Open issues with patches: 2248 Issues opened (55) ================== #23571: Raise SystemError if a function returns a result with an excep http://bugs.python.org/issue23571 reopened by berker.peksag #23573: Avoid redundant allocations in str.find and like http://bugs.python.org/issue23573 reopened by serhiy.storchaka #23720: __del__() order is broken since 3.4.0 http://bugs.python.org/issue23720 reopened by Alexey Kazantsev #23723: Provide a way to disable bytecode staleness checks http://bugs.python.org/issue23723 opened by brett.cannon #23725: update tempfile docs to say that TemporaryFile is secure http://bugs.python.org/issue23725 opened by zbysz #23726: Don't enable GC for classes that don't add new fields http://bugs.python.org/issue23726 opened by eltoder #23727: rfc2231 line continuations result in an additional newline http://bugs.python.org/issue23727 opened by Brian Peterson #23728: binascii.crc_hqx() can return negative integer http://bugs.python.org/issue23728 opened by serhiy.storchaka #23730: Document return value for ZipFile.extract() http://bugs.python.org/issue23730 opened by mjpieters #23731: Implement PEP 488 http://bugs.python.org/issue23731 opened by brett.cannon #23732: Update porting HOWTO about new -b semantics http://bugs.python.org/issue23732 opened by brett.cannon #23733: Update porting HOWTO for bytes interpolation http://bugs.python.org/issue23733 opened by brett.cannon #23734: zipimport should not check pyc timestamps against zipped py fi http://bugs.python.org/issue23734 opened by gregory.p.smith #23735: Readline not adjusting width after resize with 6.3 http://bugs.python.org/issue23735 opened by Carlos Pita #23738: Clarify documentation of positional-only default values http://bugs.python.org/issue23738 opened by vadmium #23739: locale.setlocale checks locale name for string incorrectly http://bugs.python.org/issue23739 opened by Saulius Žemaitaitis #23740: http.client request and send method have some datatype issues http://bugs.python.org/issue23740 opened by r.david.murray #23743: Python crashes upon exit if importing g++ compiled mod after i http://bugs.python.org/issue23743 opened by matham #23745: Exception when parsing an email using email.parser.BytesParser http://bugs.python.org/issue23745 opened by Elmer #23746: sysconfg.is_python_build() is buggy http://bugs.python.org/issue23746 opened by pythonhacker #23747: platform module exposes win32_ver function on posix systems http://bugs.python.org/issue23747 opened by pythonhacker #23749: asyncio missing wrap_socket http://bugs.python.org/issue23749 opened by gc #23750: Clarify difference between os.system/subprocess.call in sectio http://bugs.python.org/issue23750 opened by Andreas Sommer #23752: Cleanup io.FileIO http://bugs.python.org/issue23752 opened by haypo #23754: Add a new os.read_into() function to avoid memory copies http://bugs.python.org/issue23754 opened by haypo #23755: tempfile.NamedTemporaryFile should be able to toggle "delete" http://bugs.python.org/issue23755 opened by Stephen Gallagher #23756: Tighten definition of bytes-like objects http://bugs.python.org/issue23756 opened by vadmium #23758: Improve documenation about num_params in sqlite3 create_functi http://bugs.python.org/issue23758 opened by ced #23759: urllib.parse: make coap:// known http://bugs.python.org/issue23759 opened by chrysn #23760: Tkinter in Python 3.4 on Windows don't post internal clipboard http://bugs.python.org/issue23760 opened by Victor Korolkevich #23761: test_socket fails on Mac OSX 10.9.5 http://bugs.python.org/issue23761 opened by willingc #23762: python.org page on new-style classes should be updated http://bugs.python.org/issue23762 opened by joelthelion #23763: Chain exceptions in C http://bugs.python.org/issue23763 opened by haypo #23764: Reference inspect.Signature.bind from functools.wraps document http://bugs.python.org/issue23764 opened by productivememberofsociety666 #23765: Remove IsBadStringPtr calls in ctypes http://bugs.python.org/issue23765 opened by steve.dower #23767: Library and include paths not added when cross compiling on lo http://bugs.python.org/issue23767 opened by kernevil #23768: assert on getting the representation of a thread in atexit fun http://bugs.python.org/issue23768 opened by xdegaye #23769: valgrind reports leaks for test_zipimport http://bugs.python.org/issue23769 opened by rkuska #23770: Rework of exceptions are handled in the parser module (in vali http://bugs.python.org/issue23770 opened by haypo #23771: Timeouts on "x86 Ubuntu Shared 3.x" buildbot http://bugs.python.org/issue23771 opened by haypo #23772: pymonotonic() gone backward on "AMD64 Debian root 3.x" buildbo http://bugs.python.org/issue23772 opened by haypo #23773: importlib does not properly remove frames when invoking extern http://bugs.python.org/issue23773 opened by shiz #23774: Test failures when unable to write to install location http://bugs.python.org/issue23774 opened by steve.dower #23779: imaplib authenticate raises TypeError if authenticator tries t http://bugs.python.org/issue23779 opened by craigh #23780: Surprising behaviour when passing list to os.path.join. http://bugs.python.org/issue23780 opened by The Compiler #23781: Add private _PyErr_ReplaceException() in 2.7 http://bugs.python.org/issue23781 opened by serhiy.storchaka #23782: Leak in _PyTraceback_Add http://bugs.python.org/issue23782 opened by serhiy.storchaka #23783: Leak in PyObject_ClearWeakRefs http://bugs.python.org/issue23783 opened by serhiy.storchaka #23785: Leak in TextIOWrapper.tell() http://bugs.python.org/issue23785 opened by serhiy.storchaka #23786: test_unaligned_buffers (test.test_hash.HashEqualityTestCase) . http://bugs.python.org/issue23786 opened by petriborg #23787: sum() function docstring lists arguments incorrectly http://bugs.python.org/issue23787 opened by vsinitsyn #23788: test_urllib2_localnet.test_bad_address fails: OSError not rais http://bugs.python.org/issue23788 opened by raniere #23789: decimal.Decimal: __format__ behaviour http://bugs.python.org/issue23789 opened by MonsieurPaul #23790: When xdrlib.Packer().pack_string() fails, the Packer is corrup http://bugs.python.org/issue23790 opened by ostcar #23791: Identify Moved Lines with difflib http://bugs.python.org/issue23791 opened by bkiefer Most recent 15 issues with no replies (15) ========================================== #23791: Identify Moved Lines with difflib http://bugs.python.org/issue23791 #23779: imaplib authenticate raises TypeError if authenticator tries t http://bugs.python.org/issue23779 #23773: importlib does not properly remove frames when invoking extern http://bugs.python.org/issue23773 #23770: Rework of exceptions are handled in the parser module (in vali http://bugs.python.org/issue23770 #23768: assert on getting the representation of a thread in atexit fun http://bugs.python.org/issue23768 #23767: Library and include paths not added when cross compiling on lo http://bugs.python.org/issue23767 #23762: python.org page on new-style classes should be updated http://bugs.python.org/issue23762 #23760: Tkinter in Python 3.4 on Windows don't post internal clipboard http://bugs.python.org/issue23760 #23758: Improve documenation about num_params in sqlite3 create_functi http://bugs.python.org/issue23758 #23745: Exception when parsing an email using email.parser.BytesParser http://bugs.python.org/issue23745 #23734: zipimport should not check pyc timestamps against zipped py fi http://bugs.python.org/issue23734 #23733: Update porting HOWTO for bytes interpolation http://bugs.python.org/issue23733 #23732: Update porting HOWTO about new -b semantics http://bugs.python.org/issue23732 #23730: Document return value for ZipFile.extract() http://bugs.python.org/issue23730 #23728: binascii.crc_hqx() can return negative integer http://bugs.python.org/issue23728 Most recent 15 issues waiting for review (15) ============================================= #23790: When xdrlib.Packer().pack_string() fails, the Packer is corrup http://bugs.python.org/issue23790 #23786: test_unaligned_buffers (test.test_hash.HashEqualityTestCase) . http://bugs.python.org/issue23786 #23785: Leak in TextIOWrapper.tell() http://bugs.python.org/issue23785 #23783: Leak in PyObject_ClearWeakRefs http://bugs.python.org/issue23783 #23781: Add private _PyErr_ReplaceException() in 2.7 http://bugs.python.org/issue23781 #23780: Surprising behaviour when passing list to os.path.join. http://bugs.python.org/issue23780 #23779: imaplib authenticate raises TypeError if authenticator tries t http://bugs.python.org/issue23779 #23773: importlib does not properly remove frames when invoking extern http://bugs.python.org/issue23773 #23770: Rework of exceptions are handled in the parser module (in vali http://bugs.python.org/issue23770 #23767: Library and include paths not added when cross compiling on lo http://bugs.python.org/issue23767 #23763: Chain exceptions in C http://bugs.python.org/issue23763 #23758: Improve documenation about num_params in sqlite3 create_functi http://bugs.python.org/issue23758 #23752: Cleanup io.FileIO http://bugs.python.org/issue23752 #23738: Clarify documentation of positional-only default values http://bugs.python.org/issue23738 #23726: Don't enable GC for classes that don't add new fields http://bugs.python.org/issue23726 Top 10 most discussed issues (10) ================================= #22516: Windows Installer won't - even when using "just for me"option http://bugs.python.org/issue22516 32 msgs #23571: Raise SystemError if a function returns a result with an excep http://bugs.python.org/issue23571 19 msgs #23764: Reference inspect.Signature.bind from functools.wraps document http://bugs.python.org/issue23764 15 msgs #16328: win_add2path.py sets wrong user path http://bugs.python.org/issue16328 13 msgs #23786: test_unaligned_buffers (test.test_hash.HashEqualityTestCase) . http://bugs.python.org/issue23786 13 msgs #23763: Chain exceptions in C http://bugs.python.org/issue23763 12 msgs #23546: Windows, 'Edit withIDLE', and multiple installed versions http://bugs.python.org/issue23546 10 msgs #2211: Cookie.Morsel interface needs update http://bugs.python.org/issue2211 9 msgs #23529: Limit decompressed data when reading from LZMAFile and BZ2File http://bugs.python.org/issue23529 8 msgs #23720: __del__() order is broken since 3.4.0 http://bugs.python.org/issue23720 8 msgs Issues closed (48) ================== #4727: copyreg doesn't support keyword only arguments in __new__ http://bugs.python.org/issue4727 closed by serhiy.storchaka #11468: Improve unittest basic example in the doc http://bugs.python.org/issue11468 closed by ezio.melotti #17530: pprint could use line continuation for long bytes literals http://bugs.python.org/issue17530 closed by serhiy.storchaka #21526: Support new booleans in Tkinter http://bugs.python.org/issue21526 closed by serhiy.storchaka #21560: gzip.write changes trailer ISIZE field before type checking - http://bugs.python.org/issue21560 closed by serhiy.storchaka #21717: Exclusive mode for ZipFile and TarFile http://bugs.python.org/issue21717 closed by serhiy.storchaka #21802: Reader of BufferedRWPair is not closed if writer's close() fai http://bugs.python.org/issue21802 closed by serhiy.storchaka #22163: max_wbits set incorrectly to -zlib.MAX_WBITS in tarfile, shoul http://bugs.python.org/issue22163 closed by vadmium #22289: support.transient_internet() doesn't catch timeout on FTP test http://bugs.python.org/issue22289 closed by ned.deily #22351: NNTP constructor exception leaves socket for garbage collector http://bugs.python.org/issue22351 closed by serhiy.storchaka #22364: Improve some re error messages using regex for hints http://bugs.python.org/issue22364 closed by serhiy.storchaka #22687: horrible performance of textwrap.wrap() with a long word http://bugs.python.org/issue22687 closed by serhiy.storchaka #22832: Tweak parameter names for fcntl module http://bugs.python.org/issue22832 closed by serhiy.storchaka #22933: Misleading sentence in doc for shutil.move http://bugs.python.org/issue22933 closed by python-dev #23075: Mock backport in 2.7 relies on implementation defined behavior http://bugs.python.org/issue23075 closed by serhiy.storchaka #23252: Add support of writing to unseekable file in zipfile http://bugs.python.org/issue23252 closed by serhiy.storchaka #23314: Disabling CRT asserts in debug build http://bugs.python.org/issue23314 closed by steve.dower #23465: Implement PEP 486 - Make the Python Launcher aware of virtual http://bugs.python.org/issue23465 closed by steve.dower #23502: pprint: added support for mapping proxy http://bugs.python.org/issue23502 closed by serhiy.storchaka #23512: The list of built-in functions is not alphabetical on https:// http://bugs.python.org/issue23512 closed by ezio.melotti #23539: Content-length not set for HTTP methods expecting body when bo http://bugs.python.org/issue23539 closed by r.david.murray #23583: IDLE: printing unicode subclasses broken (again) http://bugs.python.org/issue23583 closed by serhiy.storchaka #23619: Python 3.5.0a2 installer fails on Windows http://bugs.python.org/issue23619 closed by steve.dower #23622: Deprecate unrecognized backslash+letter escapes in re http://bugs.python.org/issue23622 closed by serhiy.storchaka #23654: infinite loop in faulthandler._stack_overflow http://bugs.python.org/issue23654 closed by haypo #23657: Don't do isinstance checks in zipapp http://bugs.python.org/issue23657 closed by paul.moore #23665: Provide IDLE menu option to set command-line arguments http://bugs.python.org/issue23665 closed by terry.reedy #23671: string.Template doesn't work with the self keyword argument http://bugs.python.org/issue23671 closed by serhiy.storchaka #23688: unnecessary copying of memoryview in gzip.GzipFile.write? http://bugs.python.org/issue23688 closed by serhiy.storchaka #23704: Make deques a full MutableSequence by adding index(), insert() http://bugs.python.org/issue23704 closed by rhettinger #23705: Speed-up deque.__contains__ http://bugs.python.org/issue23705 closed by rhettinger #23724: Stack Trace should show argument value passed into a function, http://bugs.python.org/issue23724 closed by r.david.murray #23729: Import ElementTree documentation for namespaces and XPath http://bugs.python.org/issue23729 closed by rhettinger #23736: "make test" on clean py3 install on CentOS 6.2 - 2 tests fail http://bugs.python.org/issue23736 closed by r.david.murray #23737: spam http://bugs.python.org/issue23737 closed by ezio.melotti #23741: Small pprint refactoring http://bugs.python.org/issue23741 closed by serhiy.storchaka #23742: expandvars removes single quotes ( ' ) http://bugs.python.org/issue23742 closed by serhiy.storchaka #23744: Speed-up deque.__bool__ http://bugs.python.org/issue23744 closed by rhettinger #23748: platform._uname_cache is writeable http://bugs.python.org/issue23748 closed by haypo #23751: Allow reverse lookup (value-to-member) for Enum sublcasses dec http://bugs.python.org/issue23751 closed by mmuddasani #23753: Drop HAVE_FSTAT: require fstat() to compile/use Python http://bugs.python.org/issue23753 closed by haypo #23757: tuple function gives wrong answer when called on list subclass http://bugs.python.org/issue23757 closed by r.david.murray #23766: json.dumps: solidus ("/") should be escaped http://bugs.python.org/issue23766 closed by r.david.murray #23775: Fix pprint of OrderedDict http://bugs.python.org/issue23775 closed by serhiy.storchaka #23776: Don't use assert for checking arguments in pprint http://bugs.python.org/issue23776 closed by serhiy.storchaka #23777: argparse subcommand action can't be specified http://bugs.python.org/issue23777 closed by berker.peksag #23778: Add a visual distinction to multiline versionchanged blocks http://bugs.python.org/issue23778 closed by r.david.murray #23784: Reloading tokenize module leads to error http://bugs.python.org/issue23784 closed by serhiy.storchaka

1 0

Needed reviews
by Serhiy Storchaka 27 Mar '15

27 Mar '15

Here is list of my ready for review patches. It is incomplete and contains only patches for which I don't expect objections or long discussion. Most of them are relative easy and need only formal review. Most of them wait for a review many months. https://bugs.python.org/issue23681 Have -b warn when directly comparing ints and bytes https://bugs.python.org/issue23676 Add support of UnicodeTranslateError in standard error handlers https://bugs.python.org/issue23671 string.Template doesn't work with the self keyword argument https://bugs.python.org/issue23637 Outputting warnings fails when file patch is not ASCII and message is unicode on 2.7. https://bugs.python.org/issue23622 Deprecate unrecognized backslash+letter escapes in re https://bugs.python.org/issue23611 Pickle nested names (e.g. unbound methods) with protocols < 4 https://bugs.python.org/issue23583 IDLE: printing unicode subclasses broken (again) https://bugs.python.org/issue23573 Avoid redundant memory allocations in str.find and like https://bugs.python.org/issue23509 Speed up Counter operators https://bugs.python.org/issue23502 Tkinter doesn't support large integers (out of 32-bit range) https://bugs.python.org/issue23488 Random objects twice as big as necessary on 64-bit builds https://bugs.python.org/issue23466 PEP 461: Inconsistency between str and bytes formatting of integers https://bugs.python.org/issue23419 Faster default __reduce__ for classes without __init__ https://bugs.python.org/issue23290 Faster set copying https://bugs.python.org/issue23252 Add support of writing to unseekable file (e.g. socket) in zipfile https://bugs.python.org/issue23502 pprint: added support for mapping proxy https://bugs.python.org/issue23001 Accept mutable bytes-like objects in builtins that for now support only read-only bytes-like objects https://bugs.python.org/issue22995 Restrict default pickleability. Fail earlier for some types instead of producing incorrect data. https://bugs.python.org/issue22958 Constructors of weakref mapping classes don't accept "self" and "dict" keyword arguments https://bugs.python.org/issue22831 Use "with" to avoid possible fd leaks. Large patch with many simple changes. https://bugs.python.org/issue22826 Support context management protocol in bkfile and simplify Tools/freeze/bkfile.py https://bugs.python.org/issue22721 pprint output for sets and dicts is not stable https://bugs.python.org/issue22687 horrible performance of textwrap.wrap() with a long word https://bugs.python.org/issue22682 Add support of KZ1048 (RK1048) encoding https://bugs.python.org/issue22681 Add support of KOI8-T encoding https://bugs.python.org/issue23671 string.Template doesn't work with the self keyword argument https://bugs.python.org/issue23171 Accept arbitrary iterables in cvs.writerow() https://bugs.python.org/issue23136 Fix inconsistency in handling week 0 in _strptime() https://bugs.python.org/issue22557 Speed up local import https://bugs.python.org/issue22493 Deprecate the use of flags not at the start of regular expression https://bugs.python.org/issue22390 test.regrtest should complain if a test doesn't remove temporary files https://bugs.python.org/issue22364 Improve some re error messages using regex for hints https://bugs.python.org/issue22115 Add new methods to trace Tkinter variables https://bugs.python.org/issue22035 Fatal error in dbm.gdbm https://bugs.python.org/issue21802 Reader of BufferedRWPair is not closed if writer's close() fails https://bugs.python.org/issue21859 Add Python implementation of FileIO https://bugs.python.org/issue21717 Exclusive mode for ZipFile https://bugs.python.org/issue21708 Deprecate nonstandard behavior of a dumbdbm database https://bugs.python.org/issue21526 Support new booleans in Tkinter https://bugs.python.org/issue20168 Derby: Convert the _tkinter module to use Argument Clinic https://bugs.python.org/issue20159 Derby: Convert the ElementTree module to use Argument Clinic https://bugs.python.org/issue20148 Derby: Convert the _sre module to use Argument Clinic https://bugs.python.org/issue19930 os.makedirs('dir1/dir2', 0) always fails https://bugs.python.org/issue18684 Pointers point out of array bound in _sre.c https://bugs.python.org/issue18473 Some objects pickled by Python 3.x are not unpicklable in Python 2.x https://bugs.python.org/issue17711 Persistent id in pickle with protocol version 0 https://bugs.python.org/issue17530 pprint could use line continuation for long bytes literals https://bugs.python.org/issue16314 Support xz compression in distutils https://bugs.python.org/issue15490 Correct __sizeof__ support for StringIO https://bugs.python.org/issue15133 Make tkinter.getboolean() and BooleanVar.get() support Tcl_Obj and always return bool. https://bugs.python.org/issue14904 test_unicode_repr_oflw (in test_bigmem) crashes https://bugs.python.org/issue14260 Make re.groupindex non-modifiable. https://bugs.python.org/issue13583 Add support of slice indexes in sqlite3.Row https://bugs.python.org/issue11344 Add os.path.splitpath(path) function https://bugs.python.org/issue10803 Better support of bytearray objects in ctypes https://bugs.python.org/issue6598 calling email.utils.make_msgid frequently has a non-trivial probability of generating colliding ids https://bugs.python.org/issue4727 Use pickle protocol 4 in the copy module for support more types https://bugs.python.org/issue2175 Add support of character streams of InputSource object in SAX parsers https://bugs.python.org/issue433028 Add support if local flags in regular expressions. (?flag:...)

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Re: [Python-Dev] peps: New PEP 490: Chain exceptions at C level
by Serhiy Storchaka 26 Mar '15

26 Mar '15

On 26.03.15 10:08, victor.stinner wrote: > https://hg.python.org/peps/rev/7daf3bfd9586 > changeset: 5741:7daf3bfd9586 > user: Victor Stinner <victor.stinner(a)gmail.com> > date: Thu Mar 26 09:08:08 2015 +0100 > summary: > New PEP 490: Chain exceptions at C level > +Python 3.5 introduces a new private ``_PyErr_ChainExceptions()`` function which > +is enough to chain manually exceptions. It also was added in Python 3.4.3. I meditar about adding _PyErr_ReplaceException() in 2.7 for simpler backporting patches from 3.x. > +Functions like ``PyErr_SetString()`` don't chain automatically exceptions. To > +make usage of ``_PyErr_ChainExceptions()`` easier, new functions are added: > + > +* PyErr_SetStringChain(exc_type, message) > +* PyErr_FormatChaine(exc_type, format, ...) Typo. > +* PyErr_SetNoneChain(exc_type) > +* PyErr_SetObjectChain(exc_type, exc_value) I would first make these functions private, as _PyErr_ChainExceptions(). After proofing their usefulness in the stdlib, they can be made public.

3 4

libffi embedded in CPython
by Maciej Fijalkowski 26 Mar '15

26 Mar '15

After reading this http://bugs.python.org/issue23085 and remembering struggling having our own patches into cpython's libffi (but not into libffi itself), I wonder, is there any reason any more for libffi being included in CPython? Cheers, fijal

18 57

super() does not work during class initialization
by Martin Teichmann 25 Mar '15

25 Mar '15

Hi list, while a class is being initialized in a metaclass, it is not always possible to call classmethods of the class, as they might use super(), which in turn uses __class__, which is not initialized yet. I know that this is a known issue, but well, sometimes it even makes sense to fix already known issues... so I wrote a patch that moves the initialization of __class__ into type.__new__, so that one may use super() in a class once it starts existing. It's issue 23722 on the issue tracker. To illustrate what the problem is, the following code raises a RuntimeError: class Meta(type): def __init__(self, name, bases, dict): super().__init__(name, bases, dict) self.f() class A(metaclass=Meta): @classmethod def f(self): super() it works fine with my patch applied. Technically, my patch slightly changes the semantics of python if a metaclass returns something different in its __new__ than what type.__new__ returns. But I could not find any documentation of the current behavior, and also the tests don't test for it, and I consider the current behavior actually buggy. As an example let me give the following simple Singleton metaclass: class Singleton(type): def __new__(cls, name, bases, dict): return super().__new__(cls, name, bases, dict)() class A(metaclass=Singleton): def test(self): assert(isinstance(__class__, type)) A.test() The current python fails the assertion, while with my patch everything is fine, and I personally think __class__ should always actually refer to the class being defined, which means at the minimum that it is actually, well, a class. Greetings Martin

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Use ptyhon -s as default shbang for system python executables/daemons
by Orion Poplawski 25 Mar '15

25 Mar '15

We're starting a discussion in Fedora about setting the default shbang for system python executables and/or daemons to python -s or python -Es (or ?). See also: https://bugzilla.redhat.com/show_bug.cgi?id=1202151 https://fedorahosted.org/fpc/ticket/513 Basically we're wanting to avoid locally installed items causing security issues or other bad behavior, without too adversely affecting users' abilities to work around issues or intentionally alter behavior. It would be good to get some feedback from the broader python community before implementing anything, so I'm asking for feedback here. Thank you, Orion

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