[Freeipa-devel] pylint: remove unused variables

[Standa Laznicka]

On 09/23/2016 02:11 PM, Martin Basti wrote:
>
>
> On 23.09.2016 14:12, Jan Cholasta wrote:
>> On 23.9.2016 13:23, Standa Laznicka wrote:
>>> On 09/23/2016 07:28 AM, Jan Cholasta wrote:
>>>> On 22.9.2016 16:39, Martin Basti wrote:
>>>>> Hello all,
>>>>>
>>>>> In 4.5, I would like to remove all unused variables from code and 
>>>>> enable
>>>>> pylint check. Due to big amount of unused variables in the code this
>>>>> will be longterm effort.
>>>>>
>>>>> Why this?:
>>>>>
>>>>> * better code readability
>>>>>
>>>>> * removing dead code
>>>>>
>>>>> * unused variable may uncover potential bug
>>>>>
>>>>>
>>>>> It is clear what to do with unused assignments, but I need an 
>>>>> agreement
>>>>> what to do with unpacking or iteration with unused variables
>>>>>
>>>>>
>>>>> For example:
>>>>>
>>>>> for name, surname, gender in (('Martin', 'Basti', 'M'), ):
>>>>>
>>>>> name, surname, gender = user['mbasti']
>>>>>
>>>>> Where 'surname' is unused
>>>>>
>>>>>
>>>>> Pylint will detect surname as unused variable and we have to agree 
>>>>> on a
>>>>> way how to tell pylint that this variable is unused on purpose:
>>>>>
>>>>>
>>>>> 1)
>>>>>
>>>>> (
>>>>>
>>>>>    name,
>>>>>
>>>>>    surname,  # pylint: disable=unused-variable
>>>>>
>>>>>    gender
>>>>>
>>>>> ) = user['mbasti']
>>>>>
>>>>>
>>>>> I dont like this approach
>>>>
>>>> +1
>>>>
>>>>>
>>>>>
>>>>> 2)
>>>>>
>>>>> Use defined keyword: 'dummy' is default in pylint, we can set our 
>>>>> own,
>>>>> like ignored, unused
>>>>>
>>>>> name, dummy, gender = user['mbasti']
>>>>
>>>> -1, not visible enough.
>>>>
>>>>>
>>>>>
>>>>> 3)
>>>>>
>>>>> use a prefix for unused variables: '_' or 'ignore_'
>>>>>
>>>>> name, _surname, gender = user['mbasti']
>>>>
>>>> This. We have already been using it in new code for quite some time,
>>>> and it's common in other Python projects too. Don't reinvent the 
>>>> wheel.
>>>>
>>>>>
>>>>>
>>>>> 4)
>>>>>
>>>>> we can combine all :)
>>>>>
>>>>>
>>>>> For me the best is to have prefix '_' and 'dummy' keyword
>>>>
>>>> Use '_dummy', it's both :-)
>>>>
>>> +1. I would rather use _meh as it's easier to type but perhaps not that
>>> self-explanatory and not established at all, so _dummy is just fine :)
>>
>> What I'm actually suggesting is that any local variable with "_" 
>> prefix should be considered unused, so _meh would be fine as well.
>>
>
> +1 regexp '_.+' works for me

Wonderful, I'm all in.