Mailman 3 August 2013 - docs

[issue18576] Rename and document test.script_helper as test.support.script_helper
by Nick Coghlan 09 Sep '19

09 Sep '19

New submission from Nick Coghlan: tests.script_helper provides various utilities for sensibly testing scripts in a subprocess. It isn't easy for CPython developers to discover, since it is isn't documented and the file is mixed in with actual tests in the main test directory. As discussed in #15494, it should be: 1. Moved from Lib/test/ to Lib/test/support (and imports in tests adjusted accordingly) 2. Documented in Doc/library/test.rst These changes should be made on both the 3.3 and default branches to avoid spurious merge conflicts. ---------- assignee: docs@python components: Documentation, Tests messages: 193819 nosy: docs@python, ncoghlan priority: normal severity: normal status: open title: Rename and document test.script_helper as test.support.script_helper type: enhancement versions: Python 3.3, Python 3.4 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue18576> _______________________________________

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[issue12077] Harmonizing descriptor protocol documentation
by Davide Rizzo 29 Aug '19

29 Aug '19

New submission from Davide Rizzo <sorcio(a)gmail.com>: There are three sources of information for the descriptor protocol: - Data model reference (Doc/reference/datamodel.rst) - Descriptor HowTo guide (Doc/howto/descriptor.rst) - PEP 252 A developer who already knows descriptor tipically reads the first one: object.__get__(self, instance, owner) "... owner is always the owner class ..." Reading a bit further there are the ways a descriptor can be called, and the "direct call" is x.__get__(a). That is, without the third argument (owner) specified. The how-to definition is slightly different: descr.__get__(self, obj, type=None) --> value Here the arguments have different names ("type" shadowing the type bultin) and it seems to be implied that the third argument is optional. The ClassMethod example at the end of the document seems to confirm this: def __get__(self, obj, klass=None): (though another example doesn't). And the method contains an explicit check on klass being None. Also it could be confusing that through the examples in the same document many different names are used for the same argument (type, objtype, klass), and all different than the name used in the reference. Lastly the PEP is more explicit: __get__(): a function callable with one or two arguments. [...] When X is None, the optional second argument, T, should be meta-object. [...] When both X and T are specified ... One more quirk: the reference explains the distinction between data and non-data descriptors, though says nothing about __set__ raising AttributeError for read-only data descriptors. My proposal: - use the same names for __get__ arguments throughout the documentation (both the reference and the tutorial), e.g. __get__(self, instance, owner) - decide whether the third argument should be optional, or state the common usage in the reference, and fix accordingly the examples in the howto - explain data, non-data and read-only descriptors in the __set__ reference, or more simply, how the defintion of __set__ affects these things. ---------- assignee: docs@python components: Documentation messages: 135974 nosy: davide.rizzo, docs@python priority: normal severity: normal status: open title: Harmonizing descriptor protocol documentation versions: Python 2.7, Python 3.2, Python 3.3 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue12077> _______________________________________

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[issue15542] Documentation incorrectly suggests __init__ called after direct __new__ call
by Aaron Staley 26 Aug '19

26 Aug '19

New submission from Aaron Staley: The documentation for __new__ at http://docs.python.org/reference/datamodel.html#object.__new__ is: """ object.__new__(cls[, ...]) Called to create a new instance of class cls. __new__() is a static method (special-cased so you need not declare it as such) that takes the class of which an instance was requested as its first argument. The remaining arguments are those passed to the object constructor expression (the call to the class). The return value of __new__() should be the new object instance (usually an instance of cls). Typical implementations create a new instance of the class by invoking the superclass’s __new__() method using super(currentclass, cls).__new__(cls[, ...]) with appropriate arguments and then modifying the newly-created instance as necessary before returning it. If __new__() returns an instance of cls, then the new instance’s __init__() method will be invoked like __init__(self[, ...]), where self is the new instance and the remaining arguments are the same as were passed to __new__(). If __new__() does not return an instance of cls, then the new instance’s __init__() method will not be invoked. __new__() is intended mainly to allow subclasses of immutable types (like int, str, or tuple) to customize instance creation. It is also commonly overridden in custom metaclasses in order to customize class creation. """ The problem is in this line: "If __new__() returns an instance of cls, then the new instance’s __init__() method will be invoked like __init__(self[, ...]), where self is the new instance and the remaining arguments are the same as were passed to __new__()." This is only true in the context of a constructor. In particular, directly calling cls.__new__(cls) will NOT call __init__. If I define a class: class C(object): def __new__(*args, **kwargs): print 'new', args, kwargs return object.__new__(*args,**kwargs) def __init__(self): print 'init' C() will result in __new__ and __init__ being both executed, but C.__new__(C) will only create the instance of C; it will not call __init__! The original documentation described in http://bugs.python.org/issue1123716 was more correct: "__new__ must return an object... If you return an existing object, the constructor call will still call its __init__ method unless the object is an instance of a different class..." That is __init__ is only being called in the context of an external constructor call. Proposed phrasing: "If __new__() is invoked during object construction (cls()) and it returns an instance of cls, then the new instance’s __init__() method will be invoked like __init__(self[, ...]), where self is the new instance and the remaining arguments are the same as were passed to the object constructor." ---------- assignee: docs@python components: Documentation messages: 167267 nosy: Aaron.Staley, docs@python priority: normal severity: normal status: open title: Documentation incorrectly suggests __init__ called after direct __new__ call versions: Python 2.7 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue15542> _______________________________________

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[issue14112] tutorial intro talks of "shallow copy" concept without explanation
by Tshepang Lekhonkhobe 24 Aug '19

24 Aug '19

New submission from Tshepang Lekhonkhobe <tshepang(a)gmail.com>: Relevant line: http://hg.python.org/cpython/file/e2eccc906354/Doc/tutorial/introduction.rs… When the concept is introduced, it appears like there's an assumption that the reader would know what it means. I'm curious if it's that common a term that it should be taken for granted, or if it deserves a definition. ---------- assignee: docs@python components: Documentation messages: 154151 nosy: docs@python, tshepang priority: normal severity: normal status: open title: tutorial intro talks of "shallow copy" concept without explanation versions: Python 3.3 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue14112> _______________________________________

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[issue12634] Random Remarks in class documentation
by Ashutosh Swain 23 Aug '19

23 Aug '19

New submission from Ashutosh Swain <ats.engg(a)gmail.com>: URL: http://docs.python.org/tutorial/classes.html section: 9.4 Random Remarks The first sentense is bit confusing: "Data attributes override method attributes with the same name" Is it possible to change the sentense something like this: "Data attributes set through instance override method attributes with the same name" ---------- assignee: docs@python components: Documentation messages: 141073 nosy: ats.engg, docs@python priority: normal severity: normal status: open title: Random Remarks in class documentation type: feature request versions: Python 2.7 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue12634> _______________________________________

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[issue14050] Tutorial, list.sort() and items comparability
by Sandro Tosi 22 Aug '19

22 Aug '19

New submission from Sandro Tosi <sandro.tosi(a)gmail.com>: I'm providing patches for what reported at http://mail.python.org/pipermail/docs/2012-February/007481.html . I'm not sure on wording or even if we want them in the tutorial section, but I think it would be nice to have it documented nonetheless. ---------- assignee: docs@python components: Documentation files: list_sort-py27.diff keywords: patch messages: 153648 nosy: docs@python, sandro.tosi priority: normal severity: normal stage: patch review status: open title: Tutorial, list.sort() and items comparability versions: Python 2.7, Python 3.2, Python 3.3 Added file: http://bugs.python.org/file24557/list_sort-py27.diff _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue14050> _______________________________________

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[issue16697] argparse kwarg 'choices' documentation
by wim glenn 18 Aug '19

18 Aug '19

New submission from wim glenn: Any object that supports the in operator can be passed as the choices value, so dict objects, set objects, custom containers, etc. are all supported. (from http://docs.python.org/dev/library/argparse.html#choices ) Actual behaviour is contradicted by the docs - it seems the container must additionally be iterable. When using a custom container, argparse b0rks on trying to iterate through choices. Using a metavar prevents this, but it still breaks on cases where the element is not in the container. More details here: http://stackoverflow.com/questions/13833566/python-argparse-choices-from-an… ---------- assignee: docs@python components: Documentation messages: 177599 nosy: docs@python, wim.glenn priority: normal severity: normal status: open title: argparse kwarg 'choices' documentation type: enhancement versions: Python 2.7 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue16697> _______________________________________

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[issue11165] Document PyEval_Call* functions
by Nick Coghlan 08 Aug '19

08 Aug '19

New submission from Nick Coghlan <ncoghlan(a)gmail.com>: There are currently undocumented PyEval_Call* equivalents to a number of the PyObject_Call* functions. Since there are resources out there on the web that direct people to use the currently undocumented PyEval functions, it would be good to document those properly, and recommend people typically use the PyObject_Call* variants instead (as the latter include all the stack and interpreter state integrity protection code, while the PyEval variants assume that has all already been handled). ---------- assignee: docs@python components: Documentation keywords: easy messages: 128248 nosy: docs@python, ncoghlan priority: normal severity: normal stage: needs patch status: open title: Document PyEval_Call* functions versions: Python 2.7, Python 3.2, Python 3.3 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue11165> _______________________________________

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[issue13127] xml.dom.Attr.name is not labeled as read-only
by Dillon Amburgey 13 Jul '19

13 Jul '19

New submission from Dillon Amburgey <dillona(a)dillona.com>: http://docs.python.org/library/xml.dom.html#dom-attr-objects does not label the name attribute as read-only (like localName) even though it is. ---------- assignee: docs@python components: Documentation messages: 145155 nosy: dillona, docs@python priority: normal severity: normal status: open title: xml.dom.Attr.name is not labeled as read-only _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue13127> _______________________________________

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[issue12217] Cross-link docs for faulthandler, traceback and pdb
by Éric Araujo 13 Jul '19

13 Jul '19

New submission from Éric Araujo <merwok(a)netwok.org>: haypo suggested linking between traceback.print_tb and faulthandler.dump_traceback(). See also links between pdb and faulthandler could also be nice, if they explain briefly how the modules differ. ---------- assignee: docs@python components: Documentation keywords: easy messages: 137298 nosy: docs@python, eric.araujo, haypo priority: normal severity: normal stage: needs patch status: open title: Cross-link docs for faulthandler, traceback and pdb versions: Python 3.3 _______________________________________ Python tracker <report(a)bugs.python.org> <http://bugs.python.org/issue12217> _______________________________________

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