function created with partial gives invalid-name warning

[KennethNielsen]

Steps to reproduce

1. Type in a program such as:

   """Example of pylint behavior with partials"""
   
   from functools import partial
   import subprocess
   
   call = partial(subprocess.call, shell=True)
   
   call('echo "Not what I expected"')

2. Run pylint on it

Current behavior

It will give you an invalid-name error on the line: call = partial(subprocess.call, shell=True)

Expected behavior

I don't think this should raise en error.

partial return a partial object, which is a function (see https://docs.python.org/2/library/functools.html) with a little extra information attached to it, but it is non the less a function. Therefore, I think, that if the return value of partial is assigned a name (even at the module level) it should just adhere to the function naming conventions not constant ones.

I realize that special cases are annoying for all the extra code they involve, but I think this one should be worth it.

pylint --version output

pylint 1.6.4
astroid 1.4.8
Python 3.4.2 (default, Oct 19 2014, 13:31:11)
[GCC 4.9.1]

[PCManticore]

The check that verifies invalid-name doesn't care what the RHS of an assignment is, it is quite dumb and adding additional tips such as this is not worth it at the end of the day. Feel free to customize the const-rgx variable for more lax rules or disable the error locally.

[KennethNielsen]

This problem affects not only partial, but also e.g. types created with by namedtuple, which is a somewhat more central feature than partial. So I can't say that I agree, but thanks for the quick reply.

[mentalisttraceur]

Now that pylint does support proper logic for invalid-type when the RHS of an assignment is a namedtuple, can this be reopened to support partial? Maybe even the other similar constructs in the standard library? (operator.methodcaller and operator.attrgetter come to mind.)

[dandersson]

Pylint no longer complains about this case from version 2.5.0 and onward as a consequence of #3111 .

[mentalisttraceur]

@dandersson Cheers, that's good to hear, and thank you for posting an update about it on this issue!

[hippo91]

@dandersson thanks for this update!

[KennethNielsen]

Great stuff, thanks