[Python-projects] Suggestion about E1101 Instance of 'None' has no 'get' member

[Barry Scott]

Sylvain Thénault wrote:
>
>>>> Is there a way to tell pylint that self.some_object is expected to have
>>>> a certain type? If not is such a feature possible to implement?
>>>>
>>>> I'm thinking about annotation like:
>>>>        self.some_object = None # pylint: variable_type=Some
>>>>
>>>> meaning that some_object is expected to be class Some.
>>>>     
>>>>         
>>> this is certainly feasible at the astng level, the main difficulty being
>>> that comments are not in the ast and so a preparsing of the module file
>>> will be necessary (i think). Anyway we'll have to support this kind of
>>> thing at some point...
>>>
>>>   
>>>       
>> Indeed. Adding this support will make pylint significantly more useful.
>>
>> You already parse the comments to process the pylint: ones. Isn't this 
>> an extension of
>> that parsing?
>>     
>
> Well yes and no since ideally it should be at the astng level, so other
> astng based program take advantage of this information as well. Another
> idea would be to get information from lines such as :
>
> assert isinstance(self.attr, aclass)
>
> as Adrien suggested to me.
>   
That is a nice idea, especially if you pick up the info from any method 
of a class
so that it does not have to be executed at runtime of the code. 
Something like:

class Foo:
    def __init__( self ):
        self.some_object = None

    def useSome( self ):
        self.some_object.someMethod()

    def __pylint_hint( self ):
        assert isinstance( self.some_object, some_module.SomeClass )

Barry