mirror of
https://github.com/PiBrewing/craftbeerpi4.git
synced 2024-11-26 17:05:31 +01:00
66 lines
2.1 KiB
Python
66 lines
2.1 KiB
Python
# Copyright (c) 2016-2018 Claudiu Popa <pcmanticore@gmail.com>
|
|
# Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html
|
|
# For details: https://github.com/PyCQA/astroid/blob/master/COPYING.LESSER
|
|
|
|
"""Contains logic for retrieving special methods.
|
|
|
|
This implementation does not rely on the dot attribute access
|
|
logic, found in ``.getattr()``. The difference between these two
|
|
is that the dunder methods are looked with the type slots
|
|
(you can find more about these here
|
|
http://lucumr.pocoo.org/2014/8/16/the-python-i-would-like-to-see/)
|
|
As such, the lookup for the special methods is actually simpler than
|
|
the dot attribute access.
|
|
"""
|
|
import itertools
|
|
|
|
import astroid
|
|
from astroid import exceptions
|
|
|
|
|
|
def _lookup_in_mro(node, name):
|
|
attrs = node.locals.get(name, [])
|
|
|
|
nodes = itertools.chain.from_iterable(
|
|
ancestor.locals.get(name, []) for ancestor in node.ancestors(recurs=True)
|
|
)
|
|
values = list(itertools.chain(attrs, nodes))
|
|
if not values:
|
|
raise exceptions.AttributeInferenceError(attribute=name, target=node)
|
|
|
|
return values
|
|
|
|
|
|
def lookup(node, name):
|
|
"""Lookup the given special method name in the given *node*
|
|
|
|
If the special method was found, then a list of attributes
|
|
will be returned. Otherwise, `astroid.AttributeInferenceError`
|
|
is going to be raised.
|
|
"""
|
|
if isinstance(
|
|
node, (astroid.List, astroid.Tuple, astroid.Const, astroid.Dict, astroid.Set)
|
|
):
|
|
return _builtin_lookup(node, name)
|
|
if isinstance(node, astroid.Instance):
|
|
return _lookup_in_mro(node, name)
|
|
if isinstance(node, astroid.ClassDef):
|
|
return _class_lookup(node, name)
|
|
|
|
raise exceptions.AttributeInferenceError(attribute=name, target=node)
|
|
|
|
|
|
def _class_lookup(node, name):
|
|
metaclass = node.metaclass()
|
|
if metaclass is None:
|
|
raise exceptions.AttributeInferenceError(attribute=name, target=node)
|
|
|
|
return _lookup_in_mro(metaclass, name)
|
|
|
|
|
|
def _builtin_lookup(node, name):
|
|
values = node.locals.get(name, [])
|
|
if not values:
|
|
raise exceptions.AttributeInferenceError(attribute=name, target=node)
|
|
|
|
return values
|