Regression with not-callable

[dseomn]

Steps to reproduce

1. Run pylint 2.5.2 on https://github.com/dseomn/pepper-music-player/blob/d1920ec3b941b65fad630e8b067d35bde228be49/pepper_music_player/player/player_test.py.

Current behavior

pepper_music_player/player/player_test.py:283:8: E1102: self._player.next is not callable (not-callable)
pepper_music_player/player/player_test.py:292:8: E1102: self._player.next is not callable (not-callable)
pepper_music_player/player/player_test.py:301:8: E1102: self._player.next is not callable (not-callable)

Expected behavior

I don't see why those lines are not-callable. self._player.next() is defined as a regular method.

pylint --version output

pylint 2.5.2
astroid 2.4.1
Python 3.8.3rc1 (default, Apr 30 2020, 07:33:30) 
[GCC 9.3.0]

[frenck]

Experiencing the same issue on the Home Assistant project:

homeassistant/components/itunes/media_player.py:391:19: E1102: self.client.next is not callable (not-callable)

next() has been defined here: https://github.com/home-assistant/core/blob/dev/homeassistant/components/itunes/media_player.py#L141

[rukai]

I hit this as well, issue only occurs when the method is named next.

[felipe3dfx]

Same issue with generator in class method

class PaginatedResponse(Response):
    """A paginated response returned by the API"""

    @property
    def results(self):
        return self.data['results']

    @property
    def total(self):
        return self.data['paging']['total']

    @property
    def limit(self):
        return self.data['paging']['limit']

    @property
    def offset(self) -> int:
        return self.data['paging']['offset']

    def has_next(self) -> bool:
        return self.offset + self.limit < self.total

    def has_prev(self) -> bool:
        return self.offset > 0

    def next(self):
        offset = min(self.offset + self.limit, self.total)
        return self._request_with_params(offset=offset)

    def prev(self):
        offset = max(0, self.offset - self.limit)
        return self._request_with_params(offset=offset)

    def _request_with_params(self, **params):
        url = urlparse(self.url)
        query = parse_qs(url.query)
        query.update(params)

        return self._client.get(url.path, params=query)

    def __iter__(self):
        return iter(self.results)

    def auto_paging_iter(self):
        req = self

        for result in req:
            yield result

        while req.has_next():
            req = req.next()  # noqa Wait for https://github.com/PyCQA/pylint/issues/3595
            for result in req:
                yield result

[SamyCookie]

same issue for me, here a reduced test case

import typing

class A:
    def next(self):
        pass
    def wait(self):
        self.next()

no error if module 'typing' is not imported, or if the next method is rename (like _next)

[brycepg]

I can repro on master

---

It looks like this issue is only triggered in pylint:

Inference and astroid works here:

import astroid
ret = astroid.extract_node("""
import typing

class A:
    def next(self):
        return 1
    def wait(self):
        self.next() #@
""")
inferred = ret.func.inferred()
print("inferred", inferred)
print("callable", inferred[0].callable())
print("Instance", isinstance(inferred[0], astroid.Instance))

inferred [<BoundMethod next of .A at 0x126546186385440]
callable True
Instance False

But when calling your example with pylint. On line 1218 of pylint/checkers/typecheck.py:

called = safe_infer(node.func) when node.func is self.next is inferred as Const.NoneType(value=None) instead of a bound method.

strange