Variable length tuple (Tuple[T, ...]) type hint as keyword argument gives false positive as "bad-whitespace"

[tuukkamustonen]

Steps to reproduce

def foo(t: Tuple[str, ...] = None):
    pass

pylint test.py.

Current behavior

C:  1,28: No space allowed around keyword argument assignment
def foo(t: Tuple[str, ...] = None):
                           ^ (bad-whitespace)

Expected behavior

There shouldn't be violation.

http://mypy.readthedocs.io/en/latest/kinds_of_types.html#tuple-types recommends against variable length tuples:

Usually it’s a better idea to use Sequence[T] instead of Tuple[T, ...], as Sequence is also compatible with lists and other non-tuple sequences.

However, Tuple[T, ...] is supported, so pylint should support it, too.

pylint --version output

Latest from master:

No config file found, using default configuration
pylint 2.0.0
astroid 1.6.1
Python 3.5.5 (default, Mar 17 2018, 12:00:45) 
[GCC 5.4.0 20160609]

[PCManticore]

Thanks for the issue! It's not a matter of pylint not supporting Tuple[T, ...], in fact we don't :) We don't support type annotations in the same sense that mypy does. The error you're seeing is most likely a bug in our formatting checks, which are more akin to pycodestyle & flake8 checks rather than mypy. Nevertheless, this is a bug!

[amyreese]

This looks like an issue when using any type annotation with an ellipsis, including Tuple and Callable:

C:150, 0: No space allowed around keyword argument assignment
        initializer: Callable[...] = None,
                                   ^ (bad-whitespace)
C:151, 0: No space allowed around keyword argument assignment
        initargs: Tuple[Any, ...] = None,
                                  ^ (bad-whitespace)