[Python-projects] PyLint: False positive "<type> has no '<method>' member"

[Sylvain Thénault]

On Friday 24 November à 15:20, Maarten ter Huurne wrote:
> 
> Hi,
> 
> If I run PyLint on the following program:
> ===
> def radixSort(elements, keyFuncs):
>         sortList = None
>         for keyFunc in reversed(keyFuncs):
>                 if sortList is None:
>                         sortList = sorted(elements, key = keyFunc)
>                 else:
>                         sortList.sort(key = keyFunc)
>         return sortList
> ===
> It issues this warning:
> ===
> E1101:  7:radixSort: Instance of 'None' has no 'sort' member
> ===
> 
> I think this is a problem of the type inference. Even if it doesn't understand
> that in the "else" clause of "if sortList is None" it is guaranteed that
> "sortList" is not None, it should still know that "sortList" can be either None
> or a list, since "sorted" always returns a list (see the assignment in line 5).

ticket #3207 on the astng project.

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Sylvain Thénault                               LOGILAB, Paris (France)
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