Mailman 3 July 2013 - Python-Dev

lament for the demise of unbound methods
by Chris Withers 07 Jul '13

07 Jul '13

Hi All, In Python 2, I can figure out whether I have a method or a function, and, more importantly, for an unbound method, I can figure out what class the method belongs to: >>> class MyClass(object): ... def method(self): pass ... >>> MyClass.method <unbound method MyClass.method> >>> MyClass.method.im_class <class '__main__.MyClass'> There doesn't appear to be any way in Python 3 to do this, which is a little surprising and frustrating... What am I missing here? Chris -- Simplistix - Content Management, Batch Processing & Python Consulting - http://www.simplistix.co.uk

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Re: [Python-Dev] [Python-checkins] cpython (3.3): Issue #17860: explicitly mention that std* streams are opened in binary mode by
by R. David Murray 07 Jul '13

07 Jul '13

On Sat, 06 Jul 2013 10:25:19 +0200, ronald.oussoren <python-checkins(a)python.org> wrote: > http://hg.python.org/cpython/rev/a2c2ffa1a41c > changeset: 84453:a2c2ffa1a41c > branch: 3.3 > parent: 84449:df79735b21c1 > user: Ronald Oussoren <ronaldoussoren(a)mac.com> > date: Sat Jul 06 10:23:59 2013 +0200 > summary: > Issue #17860: explicitly mention that std* streams are opened in binary mode by default. > > The documentation does mention that the streams are opened in text mode > when univeral_newlines is true, but not that that they are opened in > binary mode when that argument is false and that seems to confuse at > least some users. > > files: > Doc/library/subprocess.rst | 6 ++++-- > 1 files changed, 4 insertions(+), 2 deletions(-) > > > diff --git a/Doc/library/subprocess.rst b/Doc/library/subprocess.rst > --- a/Doc/library/subprocess.rst > +++ b/Doc/library/subprocess.rst > @@ -293,7 +293,8 @@ > If *universal_newlines* is ``True``, the file objects *stdin*, *stdout* and > *stderr* will be opened as text streams in :term:`universal newlines` mode > using the encoding returned by :func:`locale.getpreferredencoding(False) > - <locale.getpreferredencoding>`. For *stdin*, line ending characters > + <locale.getpreferredencoding>`, otherwise these streams will be opened > + as binary streams. For *stdin*, line ending characters > ``'\n'`` in the input will be converted to the default line separator > :data:`os.linesep`. For *stdout* and *stderr*, all line endings in the > output will be converted to ``'\n'``. For more information see the IMO, either the default should be mentioned first, or the default should be mentioned in a parenthetical. Otherwise it sounds like newline translation is being done in both modes. Logically that makes no sense, so the above construction will likely lead to, at a minimum, an interruption in the flow for the reader, and at worse even more confusion than not mentioning it at all. --David

3 4

PEP 423 : naming conventions and recipes related to packaging
by Benoît Bryon 05 Jul '13

05 Jul '13

Hi, Here is an informational PEP proposal: http://hg.python.org/peps/file/52767ab7e140/pep-0423.txt Could you review it for style, consistency and content? Additional notes: * Original discussion posted to distutils-sig(a)python.org * started on May 2012 at http://mail.python.org/pipermail/distutils-sig/2012-May/018551.html * continues in June 2012 at http://mail.python.org/pipermail/distutils-sig/2012-June/018641.html * that's why I set "Discussion-To:<distutils-sig(a)python.org>" header. * Original document was edited as a contrib to cpython documentation: * http://bugs.python.org/issue14899 * file history at https://bitbucket.org/benoitbryon/cpython/history/Doc/packaging/packagename… * but it looked like a PEP, so posted to peps(a)python.org... Regards, Benoit (benoitbb on irc.freenode.net)

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Summary of Python tracker Issues
by Python tracker 05 Jul '13

05 Jul '13

ACTIVITY SUMMARY (2013-06-28 - 2013-07-05) 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 4072 ( +3) closed 26066 (+39) total 30138 (+42) Open issues with patches: 1803 Issues opened (32) ================== #5308: cannot marshal objects with more than 2**31 elements http://bugs.python.org/issue5308 reopened by christian.heimes #13153: IDLE crashes when pasting non-BMP unicode char on Py3 http://bugs.python.org/issue13153 reopened by serhiy.storchaka #18324: set_payload does not handle binary payloads correctly http://bugs.python.org/issue18324 opened by r.david.murray #18325: test_kqueue fails in OpenBSD http://bugs.python.org/issue18325 opened by Federico.Schwindt #18326: Not Clear Docs http://bugs.python.org/issue18326 opened by icedream91 #18327: swapped arguments in compatible_for_assignment()? http://bugs.python.org/issue18327 opened by christian.heimes #18329: for line in socket.makefile() speed degradation http://bugs.python.org/issue18329 opened by mmarkk #18330: Fix idlelib.PyShell.build_subprocess_arglist use of __import_ http://bugs.python.org/issue18330 opened by terry.reedy #18331: Document that runpy.run_path and run_module copy the module gl http://bugs.python.org/issue18331 opened by Drekin #18334: type(name, bases, dict) does not call metaclass' __prepare__ a http://bugs.python.org/issue18334 opened by Nikratio #18335: Add textwrap.dedent, .indent, as str methods. http://bugs.python.org/issue18335 opened by terry.reedy #18336: codecs: Link to readline module (history) instead of fd.readli http://bugs.python.org/issue18336 opened by guettli #18338: python --version should send output to STDOUT http://bugs.python.org/issue18338 opened by jaalto #18340: float related test has problem with Denormal Flush to Zero com http://bugs.python.org/issue18340 opened by V.E.O #18342: Use the repr of a module name for ModuleNotFoundError in ceval http://bugs.python.org/issue18342 opened by brett.cannon #18344: _bufferedreader_read_all() may leak reference to data http://bugs.python.org/issue18344 opened by christian.heimes #18345: logging: file creation options with FileHandler and friends http://bugs.python.org/issue18345 opened by pitrou #18348: Additional code pages for EBCDIC http://bugs.python.org/issue18348 opened by roskakori #18349: argparse usage should preserve () in metavars such as range(20 http://bugs.python.org/issue18349 opened by paul.j3 #18351: Incorrect variable name in importlib._bootstrap._get_sourcefil http://bugs.python.org/issue18351 opened by brett.cannon #18352: collections.Counter with added attributes are not deepcopied p http://bugs.python.org/issue18352 opened by Olivier.Gagnon #18353: PyUnicode_WRITE_CHAR macro definition missing http://bugs.python.org/issue18353 opened by Wolf.Ihlenfeldt #18354: http://www.python.org/doc/ has outdated note http://bugs.python.org/issue18354 opened by dholth #18355: Merge super() guide into documentation http://bugs.python.org/issue18355 opened by Russkel #18356: help(numpy) causes segfault on exit http://bugs.python.org/issue18356 opened by Leeward #18357: add tests for dictview set difference operations http://bugs.python.org/issue18357 opened by frasertweedale #18360: Won't install. Keeps telling me DLL is missing. http://bugs.python.org/issue18360 opened by daleastar #18361: Move dev-in-a-box to os.cpu_count() http://bugs.python.org/issue18361 opened by brett.cannon #18362: Make build_cpython.py from dev-in-a-box work outside of a box http://bugs.python.org/issue18362 opened by brett.cannon #18363: Change use of acronym tag in devinabox index.html to abbr http://bugs.python.org/issue18363 opened by brett.cannon #18364: Remove _not_found hack from importlib http://bugs.python.org/issue18364 opened by brett.cannon #18365: Idle: mock Text class and test thereof http://bugs.python.org/issue18365 opened by terry.reedy Most recent 15 issues with no replies (15) ========================================== #18364: Remove _not_found hack from importlib http://bugs.python.org/issue18364 #18363: Change use of acronym tag in devinabox index.html to abbr http://bugs.python.org/issue18363 #18362: Make build_cpython.py from dev-in-a-box work outside of a box http://bugs.python.org/issue18362 #18361: Move dev-in-a-box to os.cpu_count() http://bugs.python.org/issue18361 #18355: Merge super() guide into documentation http://bugs.python.org/issue18355 #18349: argparse usage should preserve () in metavars such as range(20 http://bugs.python.org/issue18349 #18348: Additional code pages for EBCDIC http://bugs.python.org/issue18348 #18345: logging: file creation options with FileHandler and friends http://bugs.python.org/issue18345 #18342: Use the repr of a module name for ModuleNotFoundError in ceval http://bugs.python.org/issue18342 #18336: codecs: Link to readline module (history) instead of fd.readli http://bugs.python.org/issue18336 #18330: Fix idlelib.PyShell.build_subprocess_arglist use of __import_ http://bugs.python.org/issue18330 #18325: test_kqueue fails in OpenBSD http://bugs.python.org/issue18325 #18324: set_payload does not handle binary payloads correctly http://bugs.python.org/issue18324 #18320: idle, pydoc search python on wrong path at make altinstall wit http://bugs.python.org/issue18320 #18319: gettext() cannot find translations with plural forms http://bugs.python.org/issue18319 Most recent 15 issues waiting for review (15) ============================================= #18357: add tests for dictview set difference operations http://bugs.python.org/issue18357 #18352: collections.Counter with added attributes are not deepcopied p http://bugs.python.org/issue18352 #18351: Incorrect variable name in importlib._bootstrap._get_sourcefil http://bugs.python.org/issue18351 #18349: argparse usage should preserve () in metavars such as range(20 http://bugs.python.org/issue18349 #18344: _bufferedreader_read_all() may leak reference to data http://bugs.python.org/issue18344 #18338: python --version should send output to STDOUT http://bugs.python.org/issue18338 #18334: type(name, bases, dict) does not call metaclass' __prepare__ a http://bugs.python.org/issue18334 #18324: set_payload does not handle binary payloads correctly http://bugs.python.org/issue18324 #18321: Multivolume support in tarfile module http://bugs.python.org/issue18321 #18317: gettext: DoS via crafted Plural-Forms http://bugs.python.org/issue18317 #18309: Make python slightly more relocatable http://bugs.python.org/issue18309 #18308: checkRecvmsgAddress wrong in test_socket.py (AIX failures) http://bugs.python.org/issue18308 #18305: [patch] Fast sum() for non-numbers http://bugs.python.org/issue18305 #18301: In itertools.chain.from_iterable() there is no cls argument http://bugs.python.org/issue18301 #18294: zlib module is not completly 64-bit safe http://bugs.python.org/issue18294 Top 10 most discussed issues (10) ================================= #18329: for line in socket.makefile() speed degradation http://bugs.python.org/issue18329 18 msgs #18305: [patch] Fast sum() for non-numbers http://bugs.python.org/issue18305 7 msgs #18340: float related test has problem with Denormal Flush to Zero com http://bugs.python.org/issue18340 7 msgs #18226: IDLE Unit test for FormatParagrah.py http://bugs.python.org/issue18226 6 msgs #18338: python --version should send output to STDOUT http://bugs.python.org/issue18338 6 msgs #13582: IDLE and pythonw.exe stderr problem http://bugs.python.org/issue13582 5 msgs #18335: Add textwrap.dedent, .indent, as str methods. http://bugs.python.org/issue18335 5 msgs #14455: plistlib unable to read json and binary plist files http://bugs.python.org/issue14455 4 msgs #17206: Py_XDECREF() expands its argument multiple times http://bugs.python.org/issue17206 4 msgs #18334: type(name, bases, dict) does not call metaclass' __prepare__ a http://bugs.python.org/issue18334 4 msgs Issues closed (37) ================== #4199: add shorthand global and nonlocal statements http://bugs.python.org/issue4199 closed by gregory.p.smith #7136: Idle File Menu Option Improvement http://bugs.python.org/issue7136 closed by terry.reedy #11016: Re-implementation of the stat module in C http://bugs.python.org/issue11016 closed by christian.heimes #11185: test_wait4 error on AIX http://bugs.python.org/issue11185 closed by pitrou #12520: spurious output in test_warnings http://bugs.python.org/issue12520 closed by haypo #12716: Reorganize os docs for files/dirs/fds http://bugs.python.org/issue12716 closed by akuchling #14206: multiprocessing.Queue documentation is lacking important detai http://bugs.python.org/issue14206 closed by sbt #17097: multiprocessing BaseManager serve_client() does not check EINT http://bugs.python.org/issue17097 closed by sbt #17261: multiprocessing.manager BaseManager cannot return proxies from http://bugs.python.org/issue17261 closed by sbt #17273: Pool methods can only be used by parent process. http://bugs.python.org/issue17273 closed by sbt #17914: add os.cpu_count() http://bugs.python.org/issue17914 closed by neologix #18081: test_logging failure in WarningsTest on buildbots http://bugs.python.org/issue18081 closed by terry.reedy #18103: Create a GUI test framework for Idle http://bugs.python.org/issue18103 closed by terry.reedy #18155: csv.Sniffer.has_header doesn't escape characters used in regex http://bugs.python.org/issue18155 closed by r.david.murray #18189: IDLE Improvements: Unit test for Delegator.py http://bugs.python.org/issue18189 closed by terry.reedy #18224: pyvenv pydoc.py script causing AttributeErrors on Windows http://bugs.python.org/issue18224 closed by python-dev #18237: unittest.assertRaisesRegex(p) example is wrong in docs http://bugs.python.org/issue18237 closed by terry.reedy #18240: hmac unnecessarily restricts input to "bytes" http://bugs.python.org/issue18240 closed by christian.heimes #18242: IDLE should not be replacing warnings.formatwarning http://bugs.python.org/issue18242 closed by terry.reedy #18244: Adopt C3-based linearization for improved ABC support in funct http://bugs.python.org/issue18244 closed by lukasz.langa #18288: Idle 2.7: Run Module does not set __file__ http://bugs.python.org/issue18288 closed by terry.reedy #18302: test_multiprocessing: test.support.import_module() does not ig http://bugs.python.org/issue18302 closed by brett.cannon #18312: "make distclean" deletes files under .hg directory http://bugs.python.org/issue18312 closed by python-dev #18315: Fix fileinput doc and docstrings (add 'buffer' in 2.7) http://bugs.python.org/issue18315 closed by terry.reedy #18322: test_stat nits http://bugs.python.org/issue18322 closed by pitrou #18328: Use after free in pystate.c http://bugs.python.org/issue18328 closed by christian.heimes #18332: _posix_listdir may leak FD http://bugs.python.org/issue18332 closed by christian.heimes #18333: Memory leak in _pickle.c:Unpickler_set_memo() http://bugs.python.org/issue18333 closed by christian.heimes #18337: codecs: StremReader readline() breaks on undocumented characte http://bugs.python.org/issue18337 closed by serhiy.storchaka #18339: Segfault in Unpickler_set_memo() http://bugs.python.org/issue18339 closed by christian.heimes #18341: enhancements zlib.compress/decompress to accept Py_buffer http://bugs.python.org/issue18341 closed by jcea #18343: faulthandler_register_py() may use _Py_sighandler_t previous w http://bugs.python.org/issue18343 closed by haypo #18346: Backporting of atomic file rename to Python 2.7 http://bugs.python.org/issue18346 closed by r.david.murray #18347: ElementTree corrupts cAse of closing tags when html method is http://bugs.python.org/issue18347 closed by christian.heimes #18350: Python 3 unittest framework broken? http://bugs.python.org/issue18350 closed by amaury.forgeotdarc #18358: update links to Apple Style Guide http://bugs.python.org/issue18358 closed by ronaldoussoren #18359: pickle fail to handle some class with __new__ http://bugs.python.org/issue18359 closed by amaury.forgeotdarc

1 0

Oddity in MISC/News on default
by Antoine Pitrou 05 Jul '13

05 Jul '13

Hello, In 3.4's Misc/NEWS, there's a huge section entitled "What's New in Python 3.3.1 release candidate 1". It seems it shouldn't be there, should it? Regards Antoine.

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Solving the import-deadlock case
by Pascal Chambon 03 Jul '13

03 Jul '13

Hello everyone, I'd like to bring your attention to this issue, since it touches the fundamentals of python's import workflow: http://bugs.python.org/issue17716 /I've tried to post it on the python-import ML for weeks, but it must still be blocked somewhere in a moderation queue, so here I come ^^/ TLDR version: because of the way import current works, if importing a package "temporarily" fails whereas importing one of its children succeeded, we reach an unusable state, all subsequent attempts at importing that package will fail if a "from...import" is used somewhere. Typically, it makes a web worker broken, even though the typical behaviour of such process woudl be to retry loading, again and again, the failing view. I agree that a module loading should be, as much as possible, "side effects free", and thus shouldn't have temporary errors. But well, in practice, module loading is typically the time where process-wide initialization are done (modifying sys.path, os.environ, instantiating connection or thread pools, registering atexit handler, starting maintenance threads...), so that case has chances to happen at a moment or another, especially if accesses to filesystem or network (SQL...) are done at module loading, due to the lack of initialization system at upper levels. That's why I propose modifying the behaviour of module import, so that submodules are deleted as well when a parent module import fails. True, it means they will be reloaded as well when importing the parent will start again, but anyway we already have a "double execution" problem with the reloading of the parent module, so it shouldn't make a big difference. The only other solution I'd see would be to SYSTEMATICALLY perform name (re)binding when processing a from...import statement, to recover from the previously failed initialization. Dunno if it's a good idea. On a (separate but related) topic, to be safer on module reimports or reloadings, it could be interesting to add some "idempotency" to common initialization tasks ; for example the "atexit" registration system, wouldn't it be worth adding a boolean flag to explicitely skip registration if a callable with same fully qualified name is already registered. Do you have opinions on these subjects ? thanks, regards, Pascal

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Expose stack effects to Python?
by Larry Hastings 03 Jul '13

03 Jul '13

I wrote my own assembler for Python bytecode called "Maynard". I had to statically compute the stack effects for each bytecode instruction by hand; what I did was copied and pasted opcode_stack_effect() (which is static) out of Python/compile.c and into my own driver program, then I probed it with test values to produce a table. I then coded up a function using that table, but hand-calculating the value sometimes as there are some opcodes whose stack effect varies based on the oparg. It sure would be nice if this information was simply available to the Python interpreter; theoretically it can change between point releases. Would anybody mind if I added it somewhere? I'd probably just expose opcode_stack_effect to Python, then add all this other junk to the dis module and make it available there. //arry/

4 3

Issue 18312 "fix" broke buildbots
by Eric V. Smith 03 Jul '13

03 Jul '13

I'm not sure how my change broke the buildbots, but apparently it did. I need to run to a meeting now, but I can roll this back in the next few hours. If someone else wants to roll it back before I get to it, feel free. Sorry about the problem. I tested it locally, I'm not sure how the buildbots are affected. Eric.

3 3

Why are captured parameters also listed in co_varnames?
by Andrea Griffini 02 Jul '13

02 Jul '13

I'm trying to understand how CPython implements closure variable capture and there is one minor point I can't understand. When a local is captured it gets allocated in co_cellvars and is accessed with (LOAD|STORE)_DEREF, and this is clear. However when a local is coming from a parameter it gets ALSO allocated in co_varnames even if the local slot apparently is not accesible because *_FAST opcodes are not generated. Is there a technical reason for this? It happens in CPython 2, 3 and even in PyPy... Andrea Griffini

2 1

End of the mystery "@README.txt Mercurial bug"
by Victor Stinner 01 Jul '13

01 Jul '13

Hi, One month ago, unit tests were added to IDLE (cool!) with a file called @README.txt. The @ was used to see the name on top in a listing of the directory. Some developers began to get strange Mercurial errors like: "abort: data/Lib/idlelib/idle_test/(a)README.txt.i at 7573717b9e6f: no match" " 83941: empty or missing Lib/idlelib/idle_test/(a)README.txt " etc. Senthil reported the issue on python-committers mailing list: http://mail.python.org/pipermail/python-committers/2013-May/002565.html The @ character was discussed. Replacing it with "_" was proposed. Guido asked to simply rename the name "README.txt", he wrote: "I think we have a zen rule about this: Special cases aren't special enough to break the rules." Senthil was asked to upgrade its Mercurial version. Someone supposed that it is a disk issue. Anyway, the issue disappeared with a fresh clone. I also had the issue on 3 different computers, and so I reported the issue upstream: http://bz.selenic.com/show_bug.cgi?id=3954 I discussed with a Mercurial developer, Matt, on IRC. He asked how the server is managed, if we are using only one physical server, if repositories are copied with rsync, etc. I was unable to answer, I don't have access to hg.python.org server. The issue was closed, but 20 days later (today) I reproduced the issue again. I cloned the repository at a specific revision, tried to update to another specific revision: no bug. I also played with with hg bisect, because I suspected a bug in bisect: no bug. I tried to update at each revision between 83900 and 84348 to check if @README.txt disappears from .hg/store: still no bug. I also ran fsck: no error (but the disk is mounted, so I don't know if the report is reliable). And then I ran "make distclean"... Victor

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