| msg59675 - (view) |
Author: Dieter Maurer (dmaurer) |
Date: 2008-01-10 17:39 |
| The inspect functions "getmembers(cls)" and "classify_class_attrs(cls)" require that for a class *cls* each name in "dir(cls)" can be retrieved by "getattr(cls, name)". While this holds for usual class attributes, it may well fail for descriptors (descriptors set by 'zope.interface' are a real world example for this). Attached it as small script that demonstrates the problem. The bug affects 'pydoc' and the built in 'help' (which is in fact 'pydoc.help'). While 'pydoc' and 'help' do not break completely, they can not present meaningful information for classes with some descriptors |
|
|
| msg59676 - (view) |
Author: Guido van Rossum (gvanrossum) *  |
Date: 2008-01-10 17:58 |
| Please submit a patch. |
|
|
| msg59677 - (view) |
Author: Dieter Maurer (dmaurer) |
Date: 2008-01-10 19:18 |
| In "dm.zdoc" (a "pydoc" wrapper for Zope) I simply filter out all names returned by "dir" which cannot be "getattr"ed. But, I am not sure, that this is good enough to be accepted as a patch (although it already improves upon the current state) |
|
|
| msg59684 - (view) |
Author: Antoine Pitrou (pitrou) * |
Date: 2008-01-10 23:25 |
| This is my attempt at a patch for this. It fixes inspect.getmembers and inspect.classify_class_attrs to work with Dieter's example. I hope it doesn't mess anything else. As for pydoc, things look a bit more complicated... The annoying thing is that the logic to browse object contents is duplicated inside the different renderers (pydoc.Repr subclasses). Also, I couldn't find any unit tests for pydoc. Are there any? |
|
|
| msg59712 - (view) |
Author: Antoine Pitrou (pitrou) * |
Date: 2008-01-11 14:54 |
| For the record the same problem also happens with toscawidgets. >>> from toscawidgets.widgets.forms import validators >>> help(validators) Traceback (most recent call last): File "", line 1, in File "/usr/lib/python2.5/site.py", line 351, in __call__ return pydoc.help(*args, **kwds) File "/usr/lib/python2.5/pydoc.py", line 1646, in __call__ self.help(request) File "/usr/lib/python2.5/pydoc.py", line 1690, in help else: doc(request, 'Help on %s:') File "/usr/lib/python2.5/pydoc.py", line 1481, in doc pager(title % desc + '\n\n' + text.document(object, name)) File "/usr/lib/python2.5/pydoc.py", line 324, in document if inspect.ismodule(object): return self.docmodule(*args) File "/usr/lib/python2.5/pydoc.py", line 1072, in docmodule contents.append(self.document(value, key, name)) File "/usr/lib/python2.5/pydoc.py", line 325, in document if inspect.isclass(object): return self.docclass(*args) File "/usr/lib/python2.5/pydoc.py", line 1173, in docclass classify_class_attrs(object)) File "/usr/lib/python2.5/pydoc.py", line 179, in classify_class_attrs return map(fixup, inspect.classify_class_attrs(object)) File "/usr/lib/python2.5/inspect.py", line 246, in classify_class_attrs obj = getattr(cls, name) File "/usr/lib/python2.5/site-packages/FormEncode-0.7.1-py2.5.egg/formencode/declarative.py", line 105, in __get__ obj = type.singleton() File "/usr/lib/python2.5/site-packages/FormEncode-0.7.1-py2.5.egg/formencode/declarative.py", line 166, in singleton setattr(cls, name, cls(declarative_count=cls.declarative_count)) TypeError: __init__() got an unexpected keyword argument 'declarative_count' |
|
|
| msg59743 - (view) |
Author: Antoine Pitrou (pitrou) * |
Date: 2008-01-11 20:20 |
| Here is a (hopefully complete) patch against both pydoc and inspect. It fixes one more bug compared to the previous one (descriptors can also have a special __getattr__ in addition to __get__, which gave problems when trying to access __classobj__). |
|
|
| msg67777 - (view) |
Author: Facundo Batista (facundobatista) * |
Date: 2008-06-06 16:17 |
| Really don't know why this was assigned to me... |
|
|
| msg116863 - (view) |
Author: Mark Lawrence (BreamoreBoy) * |
Date: 2010-09-19 11:15 |
| I can't apply the patch to any current SVN version. |
|
|
| msg149242 - (view) |
Author: Amaury Forgeot d'Arc (amaury.forgeotdarc) * |
Date: 2011-12-11 19:24 |
| The 'type' object now has the same issue: __abstractmethods__ appears in dir(type) but type.__abstractmethods__ fails with an AttributeError. See |
|
|
| msg149606 - (view) |
Author: Antoine Pitrou (pitrou) * |
Date: 2011-12-16 09:58 |
| Updated patch for 3.2. |
|
|
| msg149607 - (view) |
Author: Antoine Pitrou (pitrou) * |
Date: 2011-12-16 10:05 |
| Updated patch that adds a test for classifying builtin types (checks that ``inspect.classify_class_attrs(type)`` does not throw as in ). |
|
|
| msg149968 - (view) |
Author: Roundup Robot (python-dev)  |
Date: 2011-12-21 09:01 |
| New changeset 902f694a7b0e by Antoine Pitrou in branch '3.2': Issue #1785: Fix inspect and pydoc with misbehaving descriptors. http://hg.python.org/cpython/rev/902f694a7b0e New changeset b08bf8df8eec by Antoine Pitrou in branch 'default': Issue #1785: Fix inspect and pydoc with misbehaving descriptors. http://hg.python.org/cpython/rev/b08bf8df8eec |
|
|
| msg149970 - (view) |
Author: Roundup Robot (python-dev) |
Date: 2011-12-21 09:18 |
| New changeset 13f56cd8dec1 by Antoine Pitrou in branch '2.7': Issue #1785: Fix inspect and pydoc with misbehaving descriptors. http://hg.python.org/cpython/rev/13f56cd8dec1 |
|
|
| msg149973 - (view) |
Author: Antoine Pitrou (pitrou) * |
Date: 2011-12-21 09:19 |
| Now fixed in all 3 branches. |
|
|
| msg150005 - (view) |
Author: Éric Araujo (eric.araujo) * |
Date: 2011-12-21 16:10 |
| Great stuff. |
|
|
| msg151544 - (view) |
Author: Vincent Pelletier (vpelletier) |
Date: 2012-01-18 15:47 |
| This change causes the following behaviour: >>> import inspect >>> class B(object): ... def f(self): ... pass ... >>> inspect.getmembers(B, inspect.ismethod) [] While I would expect the result to contain f: >>> inspect.ismethod(B.f) True Isn't this a regression ? Regards, Vincent Pelletier |
|
|
| msg151545 - (view) |
Author: Vincent Pelletier (vpelletier) |
Date: 2012-01-18 15:49 |
| Sorry, I forgot to mention I'm using python2.7 . |
|
|
| msg151548 - (view) |
Author: Antoine Pitrou (pitrou) * |
Date: 2012-01-18 16:29 |
| Thanks for noticing. The doc for ismethod() says: “Return true if the object is a bound method written in Python.” and the docstring agrees with that: “Return true if the object is an instance method. [...]” So the change isn't properly a regression when reading the docs. On the other hand, it's true that some code may rely on the previous behaviour, and the discrepancy between getmembers() and a manual test can be confusing. By the way, Python 3 has ismethod() right: >>> class B: ... def f(self): pass ... >>> inspect.ismethod(B.f) False >>> inspect.ismethod(B().f) True |
|
|
| msg151549 - (view) |
Author: Roundup Robot (python-dev) |
Date: 2012-01-18 16:41 |
| New changeset f824744557ba by Antoine Pitrou in branch '2.7': Revert part of 13f56cd8dec1 (issue #1785) to avoid breaking getmembers() with unbound methods. http://hg.python.org/cpython/rev/f824744557ba |
|
|
| msg151550 - (view) |
Author: Antoine Pitrou (pitrou) * |
Date: 2012-01-18 16:46 |
| I've backed out the part of the changeset that "fixed" getmembers(), so the old behaviour is restored. Other parts of the changeset (that e.g. fixed pydoc) have not been reverted. |
|
|