Hi, 

The idea of plugin is very simple and I felt the need of it in my organization's code base where we use python 2.7 to write the tests.

There are a lot of functions which looks like this: def foo( var1, name1=value, *args ):

The problem that I want to deal with is that we should not have keyword arguments( name1 ) before positional arguments( *args ). Although the function can still be called by passing name1 as positional argument but there would be no way to not specify name1 but specify *args.

def foo(a, b=3, *args):

    print a, b, args

Case1: a = 0, b = 2, args = (4, 5)

foo(0, 2, 4, 5) => 0 2 (4, 5)

Case2: a = 0, b = <default_value>, args = (4, 5)

foo(0, 4, 5) => 0 4 (5, )  ==> args list modified as well as value of 'b'

And of course, we cant do this: 

foo(0, b=2, 4, 5)

I plan to put this in design_analysis checker and the check looks like this:

from astroid.test_utils import extract_node
n = extract_node('''
def test(a, b=2, *args, c=3, **kwargs):
   pass
''')

if n.args.defaults and n.args.varargs:

   print <ErrMsg>

I already checked it by loading this plugin as an external plugin in my pylintrc file and it worked as expected.

Claudio suggested that this might be a useful check, so I plan to merge it in the developing code-base.

Do let me know your thoughts!

On Wed, Aug 5, 2015 at 1:49 PM, Ahirnish Pareek <ahirnish@arista.com> wrote:

Hi,

I have never patched anything to the open-source code and I am confused as to what are the right steps to follow. I need to patch a function argument related checker into the pylint code base. Can someone point me to the steps need to follow to ensure my changes go upstream?

Thanks.

On Fri, Jul 3, 2015 at 3:02 PM, Claudiu Popa <pcmanticore@gmail.com> wrote:

On Thu, Jul 2, 2015 at 9:45 AM, Ahirnish Pareek <ahirnish@arista.com> wrote:
> Hi all,
>
> I was wondering if there's a pattern to calculate Pylint's message-id
> numbers? I know that first alphabet indicates if its a warning, error,
> convention, refactor or fatal but how do we come up with 4-digit number
> after that?
>
> Like - E1605. E = Error but what is 1605?
>
> Thanks.


Base id of standard checkers (used in msg and report ids):
01: base
02: classes
03: format
04: import
05: misc
06: variables
07: exceptions
08: similar
09: design_analysis
10: newstyle
11: typecheck
12: logging
13: string_format
14: string_constant
15: stdlib
16: python3

So for E1605, that would be from the python 3 checker. Since it's pretty
hard to remember all this, the message ids will be deprecated at some
point, in favor of using symbolic names.

--

Regards,
Ahirnish

--

Regards,
Ahirnish