Python-Dev November 2016

python-dev@python.org

47 participants
35 discussions

by Ned Batchelder

When I added Python 3.6 support to coverage.py, I posted a Mac wheel to PyPI: https://pypi.python.org/pypi/coverage/ That wheel was built against 3.6a3, the latest version at the time. When I use it now on 3.6b3, it doesn't work right. The reason is that the co_firstlineno field in PyCodeObject moved in September, as part of the PEP 523 work: https://github.com/python/cpython/commit/f1e6d88b3ca2b56d51d87b6b38ea1870c5… The docs say that PyCodeObject can change at any time, but I don't see why the field had to move in the first place. Was this needed? Am I doing the wrong thing by using PyCodeObject fields directly in the coverage.py C trace function? It seems like this was an unnecessary breaking change, even if it is a non-guaranteed interface. BTW, there are some comments that should be updated based on that commit, I can submit a patch to fix them. --Ned.

3 years, 10 months

Summary of Python tracker Issues

by Python tracker

ACTIVITY SUMMARY (2016-11-11 - 2016-11-18) 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 5584 (+25) closed 34909 (+43) total 40493 (+68) Open issues with patches: 2421 Issues opened (51) ================== #28032: --with-lto builds segfault in many situations http://bugs.python.org/issue28032 reopened by koobs #28671: SSL server requesting client certificates should send CA list http://bugs.python.org/issue28671 opened by kchen #28672: Explain in the "Data Model" document why arguments to __init__ http://bugs.python.org/issue28672 opened by João.Sebastião.de.Oliveira.Bueno #28673: When using pyro4 with more than 15 threads, python 2.7.12 core http://bugs.python.org/issue28673 opened by pwp333 #28675: about PEP 528 / PEP 529 http://bugs.python.org/issue28675 opened by Big Stone #28677: difficult to parse sentence structure in "When an instance att http://bugs.python.org/issue28677 opened by viorel #28680: bdist_wininst generated 64-bit executable looks for 3.5-32 http://bugs.python.org/issue28680 opened by Timothy Widrick #28681: About function renaming in the tutorial http://bugs.python.org/issue28681 opened by xfq #28682: Bytes support in os.fwalk() http://bugs.python.org/issue28682 opened by serhiy.storchaka #28683: bind() on a unix socket raises PermissionError on Android for http://bugs.python.org/issue28683 opened by xdegaye #28684: [asyncio] bind() on a unix socket raises PermissionError on An http://bugs.python.org/issue28684 opened by xdegaye #28685: Optimizing list.sort() by performing safety checks in advance http://bugs.python.org/issue28685 opened by elliot.gorokhovsky #28686: py.exe ignored PATH when using python3 shebang http://bugs.python.org/issue28686 opened by wdhwg001 #28687: Python 2.7.12 windows x64 installer fails after previous bad u http://bugs.python.org/issue28687 opened by Igor.Skochinsky #28688: Warning -- warnings.filters was modified by test_warnings http://bugs.python.org/issue28688 opened by haypo #28689: OpenSSL 1.1.0c test failures http://bugs.python.org/issue28689 opened by christian.heimes #28692: gettext: deprecate selecting plural form by fractional numbers http://bugs.python.org/issue28692 opened by serhiy.storchaka #28693: No HKSCS support in Windows cp950 http://bugs.python.org/issue28693 opened by Artoria2e5 #28694: tkinter interface to fontchooser http://bugs.python.org/issue28694 opened by Lance Ware #28695: Add SSL_CTX_set_client_cert_engine http://bugs.python.org/issue28695 opened by christian.heimes #28696: imap from ThreadPool hangs by an exception in a generator func http://bugs.python.org/issue28696 opened by lev-veshnyakov #28697: asyncio.Lock, Condition, Semaphore docs don't mention `async w http://bugs.python.org/issue28697 opened by ulope #28698: Python 3.x ctypes c_wchar_p return is different from official http://bugs.python.org/issue28698 opened by Alex Wang #28699: Imap from ThreadPool behaves unexpectedly http://bugs.python.org/issue28699 opened by lev-veshnyakov #28700: test_dbm failure: KeyError: b'0' (intermittent in 3.5, reliabl http://bugs.python.org/issue28700 opened by gward #28702: Confusing error message when None used in expressions, eg. "'N http://bugs.python.org/issue28702 opened by gward #28705: Clean up design FAQ question about compiling to C http://bugs.python.org/issue28705 opened by brett.cannon #28706: msvc9compiler does not find a vcvarsall.bat of Visual C++ for http://bugs.python.org/issue28706 opened by jyrkih #28707: add 'directory' option to the http.server module http://bugs.python.org/issue28707 opened by matrixise #28708: Low FD_SETSIZE limit on Windows http://bugs.python.org/issue28708 opened by David Hirschfeld #28709: PyStructSequence_NewType is broken; makes GC type without sett http://bugs.python.org/issue28709 opened by josh.r #28710: Sphinx incompatible markup in configparser.ConfigParser. http://bugs.python.org/issue28710 opened by Patrick Lehmann #28711: IDLE doesn't open http://bugs.python.org/issue28711 opened by bg90299 #28712: Non-Windows mappings for a couple of Windows code pages http://bugs.python.org/issue28712 opened by Artoria2e5 #28714: Addition to Documentation of configparser.ConfigParser.write() http://bugs.python.org/issue28714 opened by georgefischhof #28715: Check result of PyUnicode_AsUTF8 http://bugs.python.org/issue28715 opened by serhiy.storchaka #28716: Fractions instantiation revisited http://bugs.python.org/issue28716 opened by wolma #28718: '*' matches entire path in fnmatch.translate http://bugs.python.org/issue28718 opened by Jim Nasby #28719: zipfile increase in size http://bugs.python.org/issue28719 opened by X-Istence #28722: doctest example exit status http://bugs.python.org/issue28722 opened by Brainix #28724: Add method send_io, recv_io to the socket module. http://bugs.python.org/issue28724 opened by tokibito #28727: Implement comparison (x==y and x!=y) for _sre.SRE_Pattern http://bugs.python.org/issue28727 opened by haypo #28728: test_host_resolution in test_socket fails on duplicate assert http://bugs.python.org/issue28728 opened by SilentGhost #28729: Exception from sqlite3 adapter masked by sqlite3.InterfaceErro http://bugs.python.org/issue28729 opened by inglesp #28730: __reduce__ not being called in dervied extension class from da http://bugs.python.org/issue28730 opened by Jeff Reback #28731: _PyDict_NewPresized() creates too small dict http://bugs.python.org/issue28731 opened by inada.naoki #28732: spawnl crash on windows7 http://bugs.python.org/issue28732 opened by srinim #28733: Show how to use mock_open in modules other that __main__ http://bugs.python.org/issue28733 opened by butla #28735: Mock is equal to ANY but MagicMock is not http://bugs.python.org/issue28735 opened by rafael.fonseca #28736: multiprocessing.Lock() no longer has .acquire() http://bugs.python.org/issue28736 opened by Eric Leadbetter #28737: Document that tp_dealloc handler must call PyObject_GC_UnTrack http://bugs.python.org/issue28737 opened by colesbury Most recent 15 issues with no replies (15) ========================================== #28737: Document that tp_dealloc handler must call PyObject_GC_UnTrack http://bugs.python.org/issue28737 #28736: multiprocessing.Lock() no longer has .acquire() http://bugs.python.org/issue28736 #28735: Mock is equal to ANY but MagicMock is not http://bugs.python.org/issue28735 #28733: Show how to use mock_open in modules other that __main__ http://bugs.python.org/issue28733 #28722: doctest example exit status http://bugs.python.org/issue28722 #28714: Addition to Documentation of configparser.ConfigParser.write() http://bugs.python.org/issue28714 #28706: msvc9compiler does not find a vcvarsall.bat of Visual C++ for http://bugs.python.org/issue28706 #28705: Clean up design FAQ question about compiling to C http://bugs.python.org/issue28705 #28697: asyncio.Lock, Condition, Semaphore docs don't mention `async w http://bugs.python.org/issue28697 #28695: Add SSL_CTX_set_client_cert_engine http://bugs.python.org/issue28695 #28687: Python 2.7.12 windows x64 installer fails after previous bad u http://bugs.python.org/issue28687 #28683: bind() on a unix socket raises PermissionError on Android for http://bugs.python.org/issue28683 #28682: Bytes support in os.fwalk() http://bugs.python.org/issue28682 #28680: bdist_wininst generated 64-bit executable looks for 3.5-32 http://bugs.python.org/issue28680 #28672: Explain in the "Data Model" document why arguments to __init__ http://bugs.python.org/issue28672 Most recent 15 issues waiting for review (15) ============================================= #28733: Show how to use mock_open in modules other that __main__ http://bugs.python.org/issue28733 #28731: _PyDict_NewPresized() creates too small dict http://bugs.python.org/issue28731 #28728: test_host_resolution in test_socket fails on duplicate assert http://bugs.python.org/issue28728 #28727: Implement comparison (x==y and x!=y) for _sre.SRE_Pattern http://bugs.python.org/issue28727 #28724: Add method send_io, recv_io to the socket module. http://bugs.python.org/issue28724 #28716: Fractions instantiation revisited http://bugs.python.org/issue28716 #28715: Check result of PyUnicode_AsUTF8 http://bugs.python.org/issue28715 #28710: Sphinx incompatible markup in configparser.ConfigParser. http://bugs.python.org/issue28710 #28707: add 'directory' option to the http.server module http://bugs.python.org/issue28707 #28699: Imap from ThreadPool behaves unexpectedly http://bugs.python.org/issue28699 #28692: gettext: deprecate selecting plural form by fractional numbers http://bugs.python.org/issue28692 #28688: Warning -- warnings.filters was modified by test_warnings http://bugs.python.org/issue28688 #28685: Optimizing list.sort() by performing safety checks in advance http://bugs.python.org/issue28685 #28684: [asyncio] bind() on a unix socket raises PermissionError on An http://bugs.python.org/issue28684 #28683: bind() on a unix socket raises PermissionError on Android for http://bugs.python.org/issue28683 Top 10 most discussed issues (10) ================================= #28712: Non-Windows mappings for a couple of Windows code pages http://bugs.python.org/issue28712 22 msgs #28618: Decorate hot functions using __attribute__((hot)) to optimize http://bugs.python.org/issue28618 15 msgs #28731: _PyDict_NewPresized() creates too small dict http://bugs.python.org/issue28731 15 msgs #24379: Add operator.subscript as a convenience for creating slices http://bugs.python.org/issue24379 11 msgs #28688: Warning -- warnings.filters was modified by test_warnings http://bugs.python.org/issue28688 11 msgs #28727: Implement comparison (x==y and x!=y) for _sre.SRE_Pattern http://bugs.python.org/issue28727 11 msgs #24339: iso6937 encoding missing http://bugs.python.org/issue24339 10 msgs #21145: Add the @cached_property decorator http://bugs.python.org/issue21145 9 msgs #27945: Various segfaults with dict http://bugs.python.org/issue27945 9 msgs #28673: When using pyro4 with more than 15 threads, python 2.7.12 core http://bugs.python.org/issue28673 9 msgs Issues closed (43) ================== #19717: resolve() fails when the path doesn't exist http://bugs.python.org/issue19717 closed by steve.dower #21449: Replace _PyUnicode_CompareWithId with _PyUnicode_EqualToASCIII http://bugs.python.org/issue21449 closed by serhiy.storchaka #22495: merge large parts of test_binop.py and test_fractions.py http://bugs.python.org/issue22495 closed by haypo #26920: android: test_sys fails http://bugs.python.org/issue26920 closed by xdegaye #26926: test_io large file test failure on 32 bits Android platforms http://bugs.python.org/issue26926 closed by xdegaye #26929: android: test_strptime fails http://bugs.python.org/issue26929 closed by xdegaye #26931: android: test_distutils fails http://bugs.python.org/issue26931 closed by xdegaye #26934: android: test_faulthandler fails http://bugs.python.org/issue26934 closed by xdegaye #26935: android: test_os fails http://bugs.python.org/issue26935 closed by xdegaye #27854: Installed 2.7: IDLE Help disabled because help.html is missing http://bugs.python.org/issue27854 closed by steve.dower #28000: Build fails on AIX with _LINUX_SOURCE_COMPAT flag http://bugs.python.org/issue28000 closed by martin.panter #28016: test_fileio fails on AIX http://bugs.python.org/issue28016 closed by martin.panter #28531: Improve utf7 encoder memory usage http://bugs.python.org/issue28531 closed by haypo #28573: Python 3.6.0b3 64-bit has no sys._mercurial info http://bugs.python.org/issue28573 closed by steve.dower #28614: Slice limit documentation could be misinterpreted in Python 2. http://bugs.python.org/issue28614 closed by rhettinger #28631: [2.7/3.5/3.6 Regression] crash using ctypes http://bugs.python.org/issue28631 closed by doko #28632: configparser does not close files in read http://bugs.python.org/issue28632 closed by PetrPy #28637: Python startup performance regression http://bugs.python.org/issue28637 closed by haypo #28644: Document recent changes in typing.py http://bugs.python.org/issue28644 closed by gvanrossum #28648: False assert in _Py_DecodeUTF8_surrogateescape http://bugs.python.org/issue28648 closed by serhiy.storchaka #28658: IDLE: catch user cfg file error and improve error message http://bugs.python.org/issue28658 closed by terry.reedy #28662: catch also PermissionError in tests when spawning a non existe http://bugs.python.org/issue28662 closed by xdegaye #28665: Harmonize STORE_DEREF with STORE_FAST and LOAD_DEREF http://bugs.python.org/issue28665 closed by rhettinger #28668: instanciation of multiprocessing.Queue raises ImportError in t http://bugs.python.org/issue28668 closed by xdegaye #28669: Math Library Dos Attack http://bugs.python.org/issue28669 closed by haypo #28670: PEP 235: Implement on every POSIX system, and clean up the C c http://bugs.python.org/issue28670 closed by brett.cannon #28674: Spam http://bugs.python.org/issue28674 closed by zach.ware #28676: On macOS Sierra, warning: implicit declaration of function 'ge http://bugs.python.org/issue28676 closed by ned.deily #28678: tarfile extract docs inconsistent naming of parameter numeric_ http://bugs.python.org/issue28678 closed by martin.panter #28679: CGIHTTPServer displays raw python code when the url contains ' http://bugs.python.org/issue28679 closed by Yudai Fujiwara #28690: Loop in re (regular expression) processing http://bugs.python.org/issue28690 closed by haypo #28691: python3.6 -Werror -c '"\c"' fails with an assertion error http://bugs.python.org/issue28691 closed by haypo #28701: Replace PyUnicode_CompareWithASCIIString with _PyUnicode_Equal http://bugs.python.org/issue28701 closed by serhiy.storchaka #28703: Fix asyncio.iscoroutinefunction to handle Mock objects http://bugs.python.org/issue28703 closed by yselivanov #28704: Fix create_unix_server to support Path-like objects (PEP 519) http://bugs.python.org/issue28704 closed by yselivanov #28713: Recent tutorial for recent Python3 still uses IOError. http://bugs.python.org/issue28713 closed by python-dev #28717: rounding error in % operator http://bugs.python.org/issue28717 closed by mark.dickinson #28720: Add collections.abc.AsyncGenerator http://bugs.python.org/issue28720 closed by yselivanov #28721: Fix asynchronous generators athrow() and aclose() to handle St http://bugs.python.org/issue28721 closed by yselivanov #28723: tkinter, radiobutton, indicatoron=0 has no effect. http://bugs.python.org/issue28723 closed by serhiy.storchaka #28725: Awaiting an awaitable returned from an async function does not http://bugs.python.org/issue28725 closed by yselivanov #28726: py.exe launches wrong version http://bugs.python.org/issue28726 closed by pravic #28734: argparse: successive parsing wipes out nargs=? values http://bugs.python.org/issue28734 closed by ajstewart

3 years, 10 months

Warnings behave differently in Python 2 and Python 3?

by Christoph Groth

(I assume that this list is appropriate for this topic, but if it isn't, I will be grateful for being redirected to the appropriate place.) It seems that warnings behave differently in Python 2 and Python 3. Consider the following script. **************** def func(): warnings.warn("Blabla", RuntimeWarning) warnings.simplefilter("ignore") func() warnings.simplefilter("always") func() **************** When run with CPython 2.7, there is no output, when run with CPython 3.5, there is the following output: **************** /tmp/test.py:4: RuntimeWarning: Blabla warnings.warn("Blabla", RuntimeWarning) **************** Was there indeed a change of how warnings behave in Python 3? I searched, but couldn't find any documentation for this. Understanding how warnings work is especially important when testing for them. This is how I stumbled across this, in case anyone is interested: https://gitlab.kwant-project.org/kwant/kwant/issues/1#note_2608 I also note that the current documentation still uses DeprecationWarning in the example of how to suppress a warning: https://docs.python.org/dev/library/warnings.html#temporarily-suppressing-w…. Since DeprecationWarning is disabled by default in modern Python, perhaps a different warning would provide a better example?

3 years, 10 months

Summary of Python tracker Issues

by Python tracker

ACTIVITY SUMMARY (2016-11-04 - 2016-11-11) 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 5559 (+12) closed 34866 (+45) total 40425 (+57) Open issues with patches: 2418 Issues opened (37) ================== #4347: Circular dependency causes SystemError when adding new syntax http://bugs.python.org/issue4347 reopened by martin.panter #28614: Slice limit documentation is incorrect http://bugs.python.org/issue28614 opened by airwin #28615: Document clarification: Section 5.4 Complex Number http://bugs.python.org/issue28615 opened by David.Johnston #28617: Why isn't "in" called a comparison operation? http://bugs.python.org/issue28617 opened by wim.glenn #28618: Decorate hot functions using __attribute__((hot)) to optimize http://bugs.python.org/issue28618 opened by haypo #28619: [Patch] Stop using inet_ntoa() when possible. http://bugs.python.org/issue28619 opened by EdSchouten #28624: Make the `cwd` argument to `subprocess.Popen` accept a `PathLi http://bugs.python.org/issue28624 opened by cool-RR #28625: multiprocessing.Pool.imap swallows exceptions thrown by genera http://bugs.python.org/issue28625 opened by elias #28626: Tutorial: rearrange discussion of output formatting to encoura http://bugs.python.org/issue28626 opened by akuchling #28627: [alpine] shutil.copytree fail to copy a direcotry with broken http://bugs.python.org/issue28627 opened by fruch #28628: Failure to add signal handlers for any signal but SIGINT http://bugs.python.org/issue28628 opened by brotherBox #28629: Emit ResourceWarning when implicitly terminating a suspended f http://bugs.python.org/issue28629 opened by ncoghlan #28631: [2.7/3.5/3.6 Regression] crash using ctypes http://bugs.python.org/issue28631 opened by doko #28632: configparser does not close files in read http://bugs.python.org/issue28632 opened by PetrPy #28635: Update What's New for 3.6 http://bugs.python.org/issue28635 opened by Elvis.Pranskevichus #28637: Python startup performance regression http://bugs.python.org/issue28637 opened by haypo #28643: Broken makefile depends for profile-opt target http://bugs.python.org/issue28643 opened by nascheme #28644: Document recent changes in typing.py http://bugs.python.org/issue28644 opened by levkivskyi #28645: Drop __aiter__ compatibility layer from 3.7 http://bugs.python.org/issue28645 opened by yselivanov #28646: Using a read-only buffer. http://bugs.python.org/issue28646 opened by mrolle #28647: python --help: -u is misdocumented as binary mode http://bugs.python.org/issue28647 opened by arigo #28648: False assert in _Py_DecodeUTF8_surrogateescape http://bugs.python.org/issue28648 opened by xiang.zhang #28650: concurrent.futures.ThreadPoolExecutor: tasks in queue not mark http://bugs.python.org/issue28650 opened by pyfm #28651: Make objects with empty __slots__ GC types http://bugs.python.org/issue28651 opened by yselivanov #28654: sys.stdout.isatty() returns True even if redirected to NUL http://bugs.python.org/issue28654 opened by kmeyer #28655: Tests altered the execution environment in isolated mode http://bugs.python.org/issue28655 opened by serhiy.storchaka #28657: cmd.Cmd.get_help() implementation can't see do_*() methods add http://bugs.python.org/issue28657 opened by Błażej Michalik #28658: MacOsX idle don't run http://bugs.python.org/issue28658 opened by Andrew Kontokanis #28660: TextWrapper break_long_words=True, break_on_hyphens=True on lo http://bugs.python.org/issue28660 opened by maubp #28661: Fix code example in Python 3.5 telnetlib documentation http://bugs.python.org/issue28661 opened by tiabc #28662: catch also PermissionError in tests when spawning a non existe http://bugs.python.org/issue28662 opened by xdegaye #28663: Higher virtual memory usage on recent Linux versions http://bugs.python.org/issue28663 opened by Valentin.Lorentz #28665: Harmonize STORE_DEREF with STORE_FAST and LOAD_DEREF http://bugs.python.org/issue28665 opened by rhettinger #28666: Make test.support.rmtree() able to remove non-writable directo http://bugs.python.org/issue28666 opened by serhiy.storchaka #28667: FD_SETSIZE is unsigned on FreeBSD http://bugs.python.org/issue28667 opened by serhiy.storchaka #28668: instanciation of multiprocessing.Queue raises ImportError in t http://bugs.python.org/issue28668 opened by xdegaye #28669: Math Library Dos Attack http://bugs.python.org/issue28669 opened by Stone Most recent 15 issues with no replies (15) ========================================== #28667: FD_SETSIZE is unsigned on FreeBSD http://bugs.python.org/issue28667 #28666: Make test.support.rmtree() able to remove non-writable directo http://bugs.python.org/issue28666 #28663: Higher virtual memory usage on recent Linux versions http://bugs.python.org/issue28663 #28660: TextWrapper break_long_words=True, break_on_hyphens=True on lo http://bugs.python.org/issue28660 #28658: MacOsX idle don't run http://bugs.python.org/issue28658 #28657: cmd.Cmd.get_help() implementation can't see do_*() methods add http://bugs.python.org/issue28657 #28655: Tests altered the execution environment in isolated mode http://bugs.python.org/issue28655 #28650: concurrent.futures.ThreadPoolExecutor: tasks in queue not mark http://bugs.python.org/issue28650 #28648: False assert in _Py_DecodeUTF8_surrogateescape http://bugs.python.org/issue28648 #28646: Using a read-only buffer. http://bugs.python.org/issue28646 #28625: multiprocessing.Pool.imap swallows exceptions thrown by genera http://bugs.python.org/issue28625 #28624: Make the `cwd` argument to `subprocess.Popen` accept a `PathLi http://bugs.python.org/issue28624 #28619: [Patch] Stop using inet_ntoa() when possible. http://bugs.python.org/issue28619 #28608: Support creating hardlink using `pathlib` http://bugs.python.org/issue28608 #28596: on Android _bootlocale on startup relies on too many library m http://bugs.python.org/issue28596 Most recent 15 issues waiting for review (15) ============================================= #28668: instanciation of multiprocessing.Queue raises ImportError in t http://bugs.python.org/issue28668 #28667: FD_SETSIZE is unsigned on FreeBSD http://bugs.python.org/issue28667 #28666: Make test.support.rmtree() able to remove non-writable directo http://bugs.python.org/issue28666 #28665: Harmonize STORE_DEREF with STORE_FAST and LOAD_DEREF http://bugs.python.org/issue28665 #28662: catch also PermissionError in tests when spawning a non existe http://bugs.python.org/issue28662 #28651: Make objects with empty __slots__ GC types http://bugs.python.org/issue28651 #28650: concurrent.futures.ThreadPoolExecutor: tasks in queue not mark http://bugs.python.org/issue28650 #28648: False assert in _Py_DecodeUTF8_surrogateescape http://bugs.python.org/issue28648 #28645: Drop __aiter__ compatibility layer from 3.7 http://bugs.python.org/issue28645 #28644: Document recent changes in typing.py http://bugs.python.org/issue28644 #28643: Broken makefile depends for profile-opt target http://bugs.python.org/issue28643 #28637: Python startup performance regression http://bugs.python.org/issue28637 #28635: Update What's New for 3.6 http://bugs.python.org/issue28635 #28626: Tutorial: rearrange discussion of output formatting to encoura http://bugs.python.org/issue28626 #28619: [Patch] Stop using inet_ntoa() when possible. http://bugs.python.org/issue28619 Top 10 most discussed issues (10) ================================= #28637: Python startup performance regression http://bugs.python.org/issue28637 32 msgs #28635: Update What's New for 3.6 http://bugs.python.org/issue28635 15 msgs #28618: Decorate hot functions using __attribute__((hot)) to optimize http://bugs.python.org/issue28618 11 msgs #19569: Use __attribute__((deprecated)) to warn usage of deprecated fu http://bugs.python.org/issue19569 9 msgs #24329: __qualname__ and __slots__ http://bugs.python.org/issue24329 9 msgs #26934: android: test_faulthandler fails http://bugs.python.org/issue26934 8 msgs #28609: argparse claims '*' positional argument is required in error o http://bugs.python.org/issue28609 8 msgs #19717: resolve() fails when the path doesn't exist http://bugs.python.org/issue19717 7 msgs #27854: Installed 2.7: IDLE Help disabled because help.html is missing http://bugs.python.org/issue27854 7 msgs #28617: Why isn't "in" called a comparison operation? http://bugs.python.org/issue28617 7 msgs Issues closed (42) ================== #1778: SyntaxError.offset sometimes wrong http://bugs.python.org/issue1778 closed by akuchling #4713: Installing sgmlop causes xmlrpclib error http://bugs.python.org/issue4713 closed by akuchling #10605: ElementTree documentation http://bugs.python.org/issue10605 closed by akuchling #18317: gettext: DoS via crafted Plural-Forms http://bugs.python.org/issue18317 closed by serhiy.storchaka #19398: test_trace fails with -S http://bugs.python.org/issue19398 closed by serhiy.storchaka #20629: Python ctypes BigEndianStructure bitfield assignment misbehavi http://bugs.python.org/issue20629 closed by xiang.zhang #21590: Systemtap and DTrace support http://bugs.python.org/issue21590 closed by lukasz.langa #21864: Error in documentation of point 9.8 'Exceptions are classes to http://bugs.python.org/issue21864 closed by berker.peksag #23839: Clear caches after every test http://bugs.python.org/issue23839 closed by serhiy.storchaka #26969: ascynio should provide a policy to address pass-loop-everywher http://bugs.python.org/issue26969 closed by yselivanov #27781: Change sys.getfilesystemencoding() on Windows to UTF-8 http://bugs.python.org/issue27781 closed by python-dev #28123: _PyDict_GetItem_KnownHash ignores DKIX_ERROR return http://bugs.python.org/issue28123 closed by serhiy.storchaka #28485: compileall.compile_dir(workers=<negative>) does not raise Valu http://bugs.python.org/issue28485 closed by martin.panter #28543: Incomplete fast path codecs aliases in codecs doc http://bugs.python.org/issue28543 closed by berker.peksag #28555: provid also sha-1 and sha-256 also on download links http://bugs.python.org/issue28555 closed by benjamin.peterson #28563: Arbitrary code execution in gettext.c2py http://bugs.python.org/issue28563 closed by serhiy.storchaka #28574: Update bundled pip http://bugs.python.org/issue28574 closed by berker.peksag #28585: Restore docstring of os._isdir http://bugs.python.org/issue28585 closed by serhiy.storchaka #28586: Convert os.scandir to Argument Clinic http://bugs.python.org/issue28586 closed by serhiy.storchaka #28590: fstring's '{' from escape sequences does not start an expressi http://bugs.python.org/issue28590 closed by eric.smith #28593: Inconsistent itertools' predicate behaviour http://bugs.python.org/issue28593 closed by rhettinger #28613: Make get_event_loop() return the current loop if called from c http://bugs.python.org/issue28613 closed by yselivanov #28616: sys.version_info.releaselevel - 'final' or 'release' http://bugs.python.org/issue28616 closed by ned.deily #28620: Build Memory Leak http://bugs.python.org/issue28620 closed by r.david.murray #28621: Refactor duplicate code calculating digit's bit length http://bugs.python.org/issue28621 closed by serhiy.storchaka #28622: Remove redundant variable annotation test from test_grammar http://bugs.python.org/issue28622 closed by gvanrossum #28623: Let `shlex.quote` accept a `PathLike` object http://bugs.python.org/issue28623 closed by berker.peksag #28630: setup.py bdist_egg --without-source-files does not allow conso http://bugs.python.org/issue28630 closed by berker.peksag #28633: Concatenating bytes literal and f-string causes segmentation f http://bugs.python.org/issue28633 closed by eric.smith #28634: asyncio.isfuture() should support Mocks http://bugs.python.org/issue28634 closed by yselivanov #28636: strange issue with Pandas-0.19.1 on Python-3.6.0b3 http://bugs.python.org/issue28636 closed by Big Stone #28638: Creating namedtuple is too slow to be used in common stdlib (e http://bugs.python.org/issue28638 closed by rhettinger #28639: inspect.isawaitable(native_coro) returns int http://bugs.python.org/issue28639 closed by yselivanov #28640: UnicodeDecodeError: 'cp949' http://bugs.python.org/issue28640 closed by steve.dower #28641: Describe PEP 495 features in "What's New in Python 3.6" docume http://bugs.python.org/issue28641 closed by yselivanov #28642: csv reader losing rows with big files and tab delimiter http://bugs.python.org/issue28642 closed by datapythonista #28649: refleak in typing.py http://bugs.python.org/issue28649 closed by yselivanov #28652: Make loop methods reject socket kinds they do not support. http://bugs.python.org/issue28652 closed by yselivanov #28653: refleak in C functools.lru_cache http://bugs.python.org/issue28653 closed by yselivanov #28656: build error in cygwin64 ,because pthread_key_t http://bugs.python.org/issue28656 closed by serhiy.storchaka #28659: xml.etree.cElementTree.write misses opening tag http://bugs.python.org/issue28659 closed by xiang.zhang #28664: test_bz2 fails with BrokenPipeError when bunzip2 is missing http://bugs.python.org/issue28664 closed by serhiy.storchaka

3 years, 10 months

Parsing f-strings from PEP 498 -- Literal String Interpolation

by Fabio Zadrozny

Hi Python-Dev, I'm trying to get my head around on what's accepted in f-strings -- https://www.python.org/dev/peps/pep-0498/ seems very light on the details on what it does accept as an expression and how things should actually be parsed (and the current implementation still doesn't seem to be in a state for a final release, so, I thought asking on python-dev would be a reasonable option). I was thinking there'd be some grammar for it (something as https://docs.python.org/3.6/reference/grammar.html), but all I could find related to this is a quote saying that f-strings should be something as: f ' <text> { <expression> <optional !s, !r, or !a> <optional : format specifier> } <text> So, given that, is it safe to assume that <expression> would be equal to the "test" node from the official grammar? I initially thought it would obviously be, but the PEP says that using a lamda inside the expression would conflict because of the colon (which wouldn't happen if a proper grammar was actually used for this parsing as there'd be no conflict as the lamda would properly consume the colon), so, I guess some pre-parser steps takes place to separate the expression to then be parsed, so, I'm interested on knowing how exactly that should work when the implementation is finished -- lots of plus points if there's actually a grammar to back it up :) Thanks, Fabio

3 years, 10 months

Benchmarks: Comparison between Python 3.5 and Python 3.6 performance

by Victor Stinner

Hi, Antoine Pitrou asked me to compare Python 3.6 to Python 3.5. Here are results on the speed-python server using LTO compilation (but not PGO): $ python3 -m perf compare_to 2016-11-03_15-37-3.5-89f7386104e2.json 2016-11-03_15-38-3.6-c4319c0d0131.json -G --min-speed=5 Slower (17): - call_method_slots: 16.7 ms +- 0.2 ms -> 28.3 ms +- 0.7 ms: 1.70x slower - call_method: 16.9 ms +- 0.2 ms -> 28.6 ms +- 0.8 ms: 1.69x slower - call_method_unknown: 18.5 ms +- 0.2 ms -> 30.8 ms +- 0.8 ms: 1.67x slower - python_startup: 20.3 ms +- 0.7 ms -> 26.9 ms +- 0.6 ms: 1.33x slower - regex_compile: 397 ms +- 4 ms -> 482 ms +- 6 ms: 1.21x slower - mako: 42.2 ms +- 0.5 ms -> 49.7 ms +- 2.5 ms: 1.18x slower - deltablue: 17.8 ms +- 0.2 ms -> 20.1 ms +- 0.6 ms: 1.13x slower - chameleon: 29.1 ms +- 0.4 ms -> 31.9 ms +- 0.4 ms: 1.10x slower - genshi_text: 89.8 ms +- 4.2 ms -> 97.8 ms +- 1.1 ms: 1.09x slower - pickle_pure_python: 1.30 ms +- 0.02 ms -> 1.41 ms +- 0.03 ms: 1.08x slower - logging_simple: 35.8 us +- 0.7 us -> 38.4 us +- 0.7 us: 1.07x slower - sqlalchemy_declarative: 331 ms +- 3 ms -> 354 ms +- 6 ms: 1.07x slower - logging_format: 42.6 us +- 0.5 us -> 45.5 us +- 0.8 us: 1.07x slower - call_simple: 13.1 ms +- 0.4 ms -> 13.9 ms +- 0.2 ms: 1.06x slower - genshi_xml: 197 ms +- 2 ms -> 209 ms +- 2 ms: 1.06x slower - richards: 190 ms +- 5 ms -> 201 ms +- 6 ms: 1.06x slower - go: 607 ms +- 19 ms -> 640 ms +- 26 ms: 1.05x slower Faster (15): - xml_etree_iterparse: 498 ms +- 11 ms -> 230 ms +- 5 ms: 2.17x faster - unpickle_list: 10.6 us +- 0.3 us -> 7.86 us +- 0.16 us: 1.35x faster - xml_etree_parse: 345 ms +- 6 ms -> 298 ms +- 8 ms: 1.16x faster - xml_etree_generate: 362 ms +- 5 ms -> 320 ms +- 8 ms: 1.13x faster - scimark_lu: 589 ms +- 24 ms -> 523 ms +- 18 ms: 1.13x faster - regex_effbot: 5.88 ms +- 0.06 ms -> 5.23 ms +- 0.05 ms: 1.13x faster - sympy_sum: 269 ms +- 7 ms -> 244 ms +- 7 ms: 1.10x faster - spectral_norm: 317 ms +- 6 ms -> 287 ms +- 2 ms: 1.10x faster - sympy_expand: 1.25 sec +- 0.04 sec -> 1.15 sec +- 0.03 sec: 1.09x faster - xml_etree_process: 291 ms +- 5 ms -> 268 ms +- 14 ms: 1.09x faster - float: 336 ms +- 8 ms -> 310 ms +- 7 ms: 1.08x faster - regex_dna: 323 ms +- 3 ms -> 298 ms +- 3 ms: 1.08x faster - unpickle: 38.4 us +- 0.6 us -> 35.5 us +- 1.2 us: 1.08x faster - crypto_pyaes: 267 ms +- 3 ms -> 249 ms +- 2 ms: 1.07x faster - nbody: 262 ms +- 3 ms -> 246 ms +- 3 ms: 1.07x faster Benchmark hidden because not significant (31): 2to3, chaos, (...) --- call_method_* slowdown: http://bugs.python.org/issue28618 python_startup slowdown: http://bugs.python.org/issue28637 I didn't analyze results yet. Victor

3 years, 10 months

Benchmarks: Comparison between Python 2.7 and Python 3.6 performance

by Victor Stinner

(Re-post without the two attached files of 100 KB each.) Hi, You may know that I'm working on benchmarks. I regenerated all benchmark results of speed.python.org using performance 0.3.2 (benchmark suite). I started to analyze results. All results are available online on the website: https://speed.python.org/ To communicate on my work on benchmarks, I tweeted two pictures: "sympy benchmarks: Python 3.6 is between 8% and 48% faster than Python 2.7 #python #benchmark": https://twitter.com/VictorStinner/status/794289596683210760 "Python 3.6 is between 25% and 54% slower than Python 2.7 in the following benchmarks": https://twitter.com/VictorStinner/status/794305065708376069 Many people were disappointed that Python 3.6 can be up to 54% slower than Python 2.7. In fact, I know many reasons which explain that, but it's hard to summarize them in 140 characters ;-) For example, Python 3.6 is 54% slower than Python 2.7 on the benchmark pycrypto_aes. This benchmark tests a pure Python implementation of the crypto cipher AES. You may know that CPython is slow for CPU intensive functions, especially on integer and floatting point numbers. "int" in Python 3 is now "long integers" by default, which is known to be a little bit slower than "short int" of Python 2. On a more realistic benchmark (see other benchmarks), the overhead of Python 3 "long int" is negligible. AES is a typical example stressing integers. For me, it's a dummy benchmark: it doesn't make sense to use Python for AES: modern CPUs have an *hardware* implemention which is super fast. Well, I didn't have time to analyze in depth individual benchmarks. If you want to help me, here is the source code of benchmarks: https://github.com/python/performance/blob/master/performance/benchmarks/ Raw results of Python 3.6 compared to Python 2.7: ------------------- $ python3 -m perf compare_to 2016-11-03_15-36-2.7-91f024fc9b3a.json.gz 2016-11-03_15-38-3.6-c4319c0d0131.json.gz -G --min-speed=5 Slower (40): - python_startup: 7.74 ms +- 0.28 ms -> 26.9 ms +- 0.6 ms: 3.47x slower - python_startup_no_site: 4.43 ms +- 0.08 ms -> 10.4 ms +- 0.4 ms: 2.36x slower - unpickle_pure_python: 417 us +- 3 us -> 918 us +- 14 us: 2.20x slower - call_method: 16.3 ms +- 0.2 ms -> 28.6 ms +- 0.8 ms: 1.76x slower - call_method_slots: 16.2 ms +- 0.4 ms -> 28.3 ms +- 0.7 ms: 1.75x slower - call_method_unknown: 18.4 ms +- 0.2 ms -> 30.8 ms +- 0.8 ms: 1.67x slower - crypto_pyaes: 161 ms +- 2 ms -> 249 ms +- 2 ms: 1.54x slower - xml_etree_parse: 201 ms +- 5 ms -> 298 ms +- 8 ms: 1.49x slower - logging_simple: 26.4 us +- 0.3 us -> 38.4 us +- 0.7 us: 1.46x slower - logging_format: 31.3 us +- 0.4 us -> 45.5 us +- 0.8 us: 1.45x slower - pickle_pure_python: 986 us +- 9 us -> 1.41 ms +- 0.03 ms: 1.43x slower - spectral_norm: 208 ms +- 2 ms -> 287 ms +- 2 ms: 1.38x slower - logging_silent: 660 ns +- 7 ns -> 865 ns +- 31 ns: 1.31x slower - chaos: 240 ms +- 2 ms -> 314 ms +- 4 ms: 1.31x slower - go: 490 ms +- 2 ms -> 640 ms +- 26 ms: 1.31x slower - xml_etree_iterparse: 178 ms +- 2 ms -> 230 ms +- 5 ms: 1.29x slower - sqlite_synth: 8.29 us +- 0.16 us -> 10.6 us +- 0.2 us: 1.28x slower - xml_etree_process: 210 ms +- 6 ms -> 268 ms +- 14 ms: 1.28x slower - django_template: 387 ms +- 4 ms -> 484 ms +- 5 ms: 1.25x slower - fannkuch: 830 ms +- 32 ms -> 1.04 sec +- 0.03 sec: 1.25x slower - hexiom: 20.2 ms +- 0.1 ms -> 24.7 ms +- 0.2 ms: 1.22x slower - chameleon: 26.1 ms +- 0.2 ms -> 31.9 ms +- 0.4 ms: 1.22x slower - regex_compile: 395 ms +- 2 ms -> 482 ms +- 6 ms: 1.22x slower - json_dumps: 25.8 ms +- 0.2 ms -> 31.0 ms +- 0.5 ms: 1.20x slower - nqueens: 229 ms +- 2 ms -> 274 ms +- 2 ms: 1.20x slower - genshi_text: 81.9 ms +- 0.6 ms -> 97.8 ms +- 1.1 ms: 1.19x slower - raytrace: 1.17 sec +- 0.03 sec -> 1.39 sec +- 0.03 sec: 1.19x slower - scimark_monte_carlo: 240 ms +- 7 ms -> 282 ms +- 10 ms: 1.17x slower - scimark_sor: 441 ms +- 8 ms -> 517 ms +- 12 ms: 1.17x slower - deltablue: 17.4 ms +- 0.1 ms -> 20.1 ms +- 0.6 ms: 1.16x slower - sqlalchemy_declarative: 310 ms +- 3 ms -> 354 ms +- 6 ms: 1.14x slower - call_simple: 12.2 ms +- 0.2 ms -> 13.9 ms +- 0.2 ms: 1.14x slower - scimark_fft: 613 ms +- 19 ms -> 694 ms +- 23 ms: 1.13x slower - meteor_contest: 191 ms +- 1 ms -> 215 ms +- 2 ms: 1.13x slower - pathlib: 46.9 ms +- 0.4 ms -> 52.6 ms +- 0.9 ms: 1.12x slower - richards: 181 ms +- 1 ms -> 201 ms +- 6 ms: 1.11x slower - genshi_xml: 191 ms +- 2 ms -> 209 ms +- 2 ms: 1.10x slower - float: 290 ms +- 5 ms -> 310 ms +- 7 ms: 1.07x slower - scimark_sparse_mat_mult: 8.19 ms +- 0.22 ms -> 8.74 ms +- 0.15 ms: 1.07x slower - xml_etree_generate: 302 ms +- 3 ms -> 320 ms +- 8 ms: 1.06x slower Faster (15): - telco: 707 ms +- 22 ms -> 22.1 ms +- 0.4 ms: 32.04x faster - unpickle_list: 15.0 us +- 0.3 us -> 7.86 us +- 0.16 us: 1.90x faster - pickle_list: 14.7 us +- 0.2 us -> 9.12 us +- 0.38 us: 1.61x faster - json_loads: 98.7 us +- 2.3 us -> 62.3 us +- 0.7 us: 1.58x faster - pickle: 40.4 us +- 0.6 us -> 27.1 us +- 0.5 us: 1.49x faster - sympy_sum: 361 ms +- 10 ms -> 244 ms +- 7 ms: 1.48x faster - sympy_expand: 1.68 sec +- 0.02 sec -> 1.15 sec +- 0.03 sec: 1.47x faster - regex_v8: 62.0 ms +- 0.5 ms -> 47.2 ms +- 0.6 ms: 1.31x faster - sympy_str: 699 ms +- 22 ms -> 537 ms +- 15 ms: 1.30x faster - regex_effbot: 6.67 ms +- 0.04 ms -> 5.23 ms +- 0.05 ms: 1.28x faster - mako: 61.5 ms +- 0.7 ms -> 49.7 ms +- 2.5 ms: 1.24x faster - html5lib: 298 ms +- 7 ms -> 261 ms +- 6 ms: 1.14x faster - sympy_integrate: 55.9 ms +- 0.3 ms -> 51.8 ms +- 1.0 ms: 1.08x faster - pickle_dict: 69.4 us +- 0.9 us -> 65.2 us +- 3.2 us: 1.06x faster - scimark_lu: 551 ms +- 26 ms -> 523 ms +- 18 ms: 1.05x faster Benchmark hidden because not significant (8): 2to3, dulwich_log, nbody, pidigits, regex_dna, tornado_http, unpack_sequence, unpickle Ignored benchmarks (3) of 2016-11-03_15-36-2.7-91f024fc9b3a.json: hg_startup, pyflate, spambayes ------------------- Please ignore call_method, call_method_slots, call_method_unknown benchmarks: it seems like I had an issue on the benchmark server. I was unable to reproduce he 70% slowdown on my laptop. JSON files if you want to analyze them yourself: http://www.haypocalc.com/tmp/2016-11-03_15-36-2.7-91f024fc9b3a.json.gz http://www.haypocalc.com/tmp/2016-11-03_15-38-3.6-c4319c0d0131.json.gz I hope that my work on benchmarks will motive some developers to look closer at Python 3 performance to find interesting optimizations ;-) Victor

3 years, 10 months

Installing Python on Windows

by Steve Dower

Hi all Those of you who follow me on Twitter (@zooba) may have noticed that I posted one of my rare blog posts over the weekend about the increasing range of Python installers available for Windows. I figured I'd draw some attention here in case others are interested in my rationale for why the main installer is how it is, and why I'm also experimenting with other forms of installer or package: http://stevedower.id.au/blog/why-so-many-python-installers/ Arguably this would make a good section in the docs or a PEP, though it's very point-in-time content, so a blog seems fine for now. There's also not really anything in the docs about how Linux distributors package up CPython, so maybe it's best as entirely standalone content. Cheers, Steve (In case anyone is suspicious, I earn no income from my blog and there are no ads. So I hope I'm not promoting the link for selfish reasons :) )

3 years, 10 months

Benchmarks: Comparison between Python 2.7 and Python 3.6 performance

by Victor Stinner

Hi, You may know that I'm working on benchmarks. I regenerated all benchmark results of speed.python.org using performance 0.3.2 (benchmark suite). I started to analyze results. All results are available online on the website: https://speed.python.org/ To communicate on my work on benchmarks, I tweeted two pictures: "sympy benchmarks: Python 3.6 is between 8% and 48% faster than Python 2.7 #python #benchmark": https://twitter.com/VictorStinner/status/794289596683210760 "Python 3.6 is between 25% and 54% slower than Python 2.7 in the following benchmarks": https://twitter.com/VictorStinner/status/794305065708376069 Many people were disappointed that Python 3.6 can be up to 54% slower than Python 2.7. In fact, I know many reasons which explain that, but it's hard to summarize them in 140 characters ;-) For example, Python 3.6 is 54% slower than Python 2.7 on the benchmark pycrypto_aes. This benchmark tests a pure Python implementation of the crypto cipher AES. You may know that CPython is slow for CPU intensive functions, especially on integer and floatting point numbers. "int" in Python 3 is now "long integers" by default, which is known to be a little bit slower than "short int" of Python 2. On a more realistic benchmark (see other benchmarks), the overhead of Python 3 "long int" is negligible. AES is a typical example stressing integers. For me, it's a dummy benchmark: it doesn't make sense to use Python for AES: modern CPUs have an *hardware* implemention which is super fast. Well, I didn't have time to analyze in depth individual benchmarks. If you want to help me, here is the source code of benchmarks: https://github.com/python/performance/blob/master/performance/benchmarks/ Raw results of Python 3.6 compared to Python 2.7: ------------------- $ python3 -m perf compare_to 2016-11-03_15-36-2.7-91f024fc9b3a.json.gz 2016-11-03_15-38-3.6-c4319c0d0131.json.gz -G --min-speed=5 Slower (40): - python_startup: 7.74 ms +- 0.28 ms -> 26.9 ms +- 0.6 ms: 3.47x slower - python_startup_no_site: 4.43 ms +- 0.08 ms -> 10.4 ms +- 0.4 ms: 2.36x slower - unpickle_pure_python: 417 us +- 3 us -> 918 us +- 14 us: 2.20x slower - call_method: 16.3 ms +- 0.2 ms -> 28.6 ms +- 0.8 ms: 1.76x slower - call_method_slots: 16.2 ms +- 0.4 ms -> 28.3 ms +- 0.7 ms: 1.75x slower - call_method_unknown: 18.4 ms +- 0.2 ms -> 30.8 ms +- 0.8 ms: 1.67x slower - crypto_pyaes: 161 ms +- 2 ms -> 249 ms +- 2 ms: 1.54x slower - xml_etree_parse: 201 ms +- 5 ms -> 298 ms +- 8 ms: 1.49x slower - logging_simple: 26.4 us +- 0.3 us -> 38.4 us +- 0.7 us: 1.46x slower - logging_format: 31.3 us +- 0.4 us -> 45.5 us +- 0.8 us: 1.45x slower - pickle_pure_python: 986 us +- 9 us -> 1.41 ms +- 0.03 ms: 1.43x slower - spectral_norm: 208 ms +- 2 ms -> 287 ms +- 2 ms: 1.38x slower - logging_silent: 660 ns +- 7 ns -> 865 ns +- 31 ns: 1.31x slower - chaos: 240 ms +- 2 ms -> 314 ms +- 4 ms: 1.31x slower - go: 490 ms +- 2 ms -> 640 ms +- 26 ms: 1.31x slower - xml_etree_iterparse: 178 ms +- 2 ms -> 230 ms +- 5 ms: 1.29x slower - sqlite_synth: 8.29 us +- 0.16 us -> 10.6 us +- 0.2 us: 1.28x slower - xml_etree_process: 210 ms +- 6 ms -> 268 ms +- 14 ms: 1.28x slower - django_template: 387 ms +- 4 ms -> 484 ms +- 5 ms: 1.25x slower - fannkuch: 830 ms +- 32 ms -> 1.04 sec +- 0.03 sec: 1.25x slower - hexiom: 20.2 ms +- 0.1 ms -> 24.7 ms +- 0.2 ms: 1.22x slower - chameleon: 26.1 ms +- 0.2 ms -> 31.9 ms +- 0.4 ms: 1.22x slower - regex_compile: 395 ms +- 2 ms -> 482 ms +- 6 ms: 1.22x slower - json_dumps: 25.8 ms +- 0.2 ms -> 31.0 ms +- 0.5 ms: 1.20x slower - nqueens: 229 ms +- 2 ms -> 274 ms +- 2 ms: 1.20x slower - genshi_text: 81.9 ms +- 0.6 ms -> 97.8 ms +- 1.1 ms: 1.19x slower - raytrace: 1.17 sec +- 0.03 sec -> 1.39 sec +- 0.03 sec: 1.19x slower - scimark_monte_carlo: 240 ms +- 7 ms -> 282 ms +- 10 ms: 1.17x slower - scimark_sor: 441 ms +- 8 ms -> 517 ms +- 12 ms: 1.17x slower - deltablue: 17.4 ms +- 0.1 ms -> 20.1 ms +- 0.6 ms: 1.16x slower - sqlalchemy_declarative: 310 ms +- 3 ms -> 354 ms +- 6 ms: 1.14x slower - call_simple: 12.2 ms +- 0.2 ms -> 13.9 ms +- 0.2 ms: 1.14x slower - scimark_fft: 613 ms +- 19 ms -> 694 ms +- 23 ms: 1.13x slower - meteor_contest: 191 ms +- 1 ms -> 215 ms +- 2 ms: 1.13x slower - pathlib: 46.9 ms +- 0.4 ms -> 52.6 ms +- 0.9 ms: 1.12x slower - richards: 181 ms +- 1 ms -> 201 ms +- 6 ms: 1.11x slower - genshi_xml: 191 ms +- 2 ms -> 209 ms +- 2 ms: 1.10x slower - float: 290 ms +- 5 ms -> 310 ms +- 7 ms: 1.07x slower - scimark_sparse_mat_mult: 8.19 ms +- 0.22 ms -> 8.74 ms +- 0.15 ms: 1.07x slower - xml_etree_generate: 302 ms +- 3 ms -> 320 ms +- 8 ms: 1.06x slower Faster (15): - telco: 707 ms +- 22 ms -> 22.1 ms +- 0.4 ms: 32.04x faster - unpickle_list: 15.0 us +- 0.3 us -> 7.86 us +- 0.16 us: 1.90x faster - pickle_list: 14.7 us +- 0.2 us -> 9.12 us +- 0.38 us: 1.61x faster - json_loads: 98.7 us +- 2.3 us -> 62.3 us +- 0.7 us: 1.58x faster - pickle: 40.4 us +- 0.6 us -> 27.1 us +- 0.5 us: 1.49x faster - sympy_sum: 361 ms +- 10 ms -> 244 ms +- 7 ms: 1.48x faster - sympy_expand: 1.68 sec +- 0.02 sec -> 1.15 sec +- 0.03 sec: 1.47x faster - regex_v8: 62.0 ms +- 0.5 ms -> 47.2 ms +- 0.6 ms: 1.31x faster - sympy_str: 699 ms +- 22 ms -> 537 ms +- 15 ms: 1.30x faster - regex_effbot: 6.67 ms +- 0.04 ms -> 5.23 ms +- 0.05 ms: 1.28x faster - mako: 61.5 ms +- 0.7 ms -> 49.7 ms +- 2.5 ms: 1.24x faster - html5lib: 298 ms +- 7 ms -> 261 ms +- 6 ms: 1.14x faster - sympy_integrate: 55.9 ms +- 0.3 ms -> 51.8 ms +- 1.0 ms: 1.08x faster - pickle_dict: 69.4 us +- 0.9 us -> 65.2 us +- 3.2 us: 1.06x faster - scimark_lu: 551 ms +- 26 ms -> 523 ms +- 18 ms: 1.05x faster Benchmark hidden because not significant (8): 2to3, dulwich_log, nbody, pidigits, regex_dna, tornado_http, unpack_sequence, unpickle Ignored benchmarks (3) of 2016-11-03_15-36-2.7-91f024fc9b3a.json: hg_startup, pyflate, spambayes ------------------- Please ignore call_method, call_method_slots, call_method_unknown benchmarks: it seems like I had an issue on the benchmark server. I was unable to reproduce he 70% slowdown on my laptop. I attached the two compressed JSON files to this email if you want to analyze them yourself. I hope that my work on benchmarks will motive some developers to look closer at Python 3 performance to find interesting optimizations ;-) Victor

3 years, 10 months

itertools predicates

by Francisco Couzo

Some functions that take a predicate from itertools accept None as its predicate: >>> list(itertools.filterfalse(None, range(10))) [0] >>> list(itertools.groupby([0,0,1,1], None)) [(0, <itertools._grouper object at 0x7fedc2047198>), (1, <itertools._grouper object at 0x7fedc2 0471d0>)] While others don't: >>> list(itertools.dropwhile(None, range(10))) Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: 'NoneType' object is not callable I'd be interested in writing a patch to make itertools more consistent if there's a consensus. I see two possible solutions: - Either remove None as a predicate parameter, which would not be backwards compatible. - Or make the functions that don't accept None start accepting it.

3 years, 10 months

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Python-Dev November 2016