Issue1727

The following code fails to run in Jython:


$ jython 
Jython 2.5.2 (Release_2_5_2:7206, Mar 2 2011, 23:12:06) 
[Java HotSpot(TM) 64-Bit Server VM (Apple Inc.)] on java1.6.0_24
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
import os
>>> args = ('/Users/offline/projects/PyHamcrest/pytest.ini',)
args = ('/Users/offline/projects/PyHamcrest/pytest.ini',)
>>> os.stat(*args)
os.stat(*args)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'builtin_function_or_method' object is not callable
>>> os.stat('/Users/offline/projects/PyHamcrest/pytest.ini')
os.stat('/Users/offline/projects/PyHamcrest/pytest.ini')
(33188, 24017506L, 234881026L, 1, 501, 20, 47L, 1301777760, 1301777759, 1301777759)

This bug seems to be also preventing RPyC from working properly under Jython.

The attached patch fixes the problem. How do I make sure it doesn't break anything elsewhere?

This fix wouldn't break anything but it actually makes the stat callpath slower (patch would make it go through reflection). stat is actually perf critical in some cases. We need the fix to be on the PyBuiltinFunctions

Probably adding an override that takes PyObject[], String[] would solve the problem. This is an odd bug though because I'm surprised it's not getting to the currently defined __call__ override automatically. We might have an issue on how we are dealing with PyObject.__call__ overrides

But we can go ahead with a local fix in the StatFunction classes for now

I think I see the problem, PyBuiltinFunctions are made to always override the __call__(PyObject[] String[]) method. Whereas we want to define this is a "narrower" override: so try making the StatFunctions subclass PyBuiltinFunctionNarrow instead of PyBuiltinFunction

also, I suppose this could use a testcase

Attached is a better fix that does not cause performance degradation.

Also, the problem affecting RPyC, although superficially similar, is something else entirely. It is still likely a Jython bug though.

applied in r7285 & r7286, thanks!