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""" Checks assigning attributes not found in class slots
will trigger assigning-non-slot warning.
"""
# pylint: disable=too-few-public-methods, missing-docstring, import-error, redundant-u-string-prefix, unnecessary-dunder-call
# pylint: disable=attribute-defined-outside-init
from collections import deque
from missing import Unknown
class Empty:
""" empty """
class Bad:
""" missing not in slots. """
__slots__ = ['member']
def __init__(self):
self.missing = 42 # [assigning-non-slot]
class Bad2:
""" missing not in slots """
__slots__ = [deque.__name__, 'member']
def __init__(self):
self.deque = 42
self.missing = 42 # [assigning-non-slot]
class Bad3(Bad):
""" missing not found in slots """
__slots__ = ['component']
def __init__(self):
self.component = 42
self.member = 24
self.missing = 42 # [assigning-non-slot]
super().__init__()
class Good(Empty):
""" missing not in slots, but Empty doesn't
specify __slots__.
"""
__slots__ = ['a']
def __init__(self):
self.missing = 42
class Good2:
""" Using __dict__ in slots will be safe. """
__slots__ = ['__dict__', 'comp']
def __init__(self):
self.comp = 4
self.missing = 5
class PropertyGood:
""" Using properties is safe. """
__slots__ = ['tmp', '_value']
@property
def test(self):
return self._value
@test.setter
def test(self, value):
# pylint: disable=attribute-defined-outside-init
self._value = value
def __init__(self):
self.test = 42
class PropertyGood2:
""" Using properties in the body of the class is safe. """
__slots__ = ['_value']
def _getter(self):
return self._value
def _setter(self, value):
# pylint: disable=attribute-defined-outside-init
self._value = value
test = property(_getter, _setter)
def __init__(self):
self.test = 24
class UnicodeSlots:
"""Using unicode objects in __slots__ is okay.
On Python 3.3 onward, u'' is equivalent to '',
so this test should be safe for both versions.
"""
__slots__ = (u'first', u'second')
def __init__(self):
self.first = 42
self.second = 24
class DataDescriptor:
def __init__(self, name, default=''):
self.__name = name
self.__default = default
def __get__(self, inst, cls):
return getattr(inst, self.__name, self.__default)
def __set__(self, inst, value):
setattr(inst, self.__name, value)
class NonDataDescriptor:
def __get__(self, inst, cls):
return 42
class SlotsWithDescriptor:
__slots__ = ['_err']
data_descriptor = DataDescriptor('_err')
non_data_descriptor = NonDataDescriptor()
missing_descriptor = Unknown()
def dont_emit_for_descriptors():
inst = SlotsWithDescriptor()
# This should not emit, because attr is
# a data descriptor
inst.data_descriptor = 'foo'
inst.non_data_descriptor = 'lala'
class ClassWithSlots:
__slots__ = ['foobar']
class ClassReassigningDunderClass:
__slots__ = ['foobar']
def release(self):
self.__class__ = ClassWithSlots
class ClassReassingingInvalidLayoutClass:
__slots__ = []
def release(self):
self.__class__ = ClassWithSlots # [assigning-non-slot]
self.test = 'test' # [assigning-non-slot]
# pylint: disable=attribute-defined-outside-init
class ClassHavingUnknownAncestors(Unknown):
__slots__ = ['yo']
def test(self):
self.not_yo = 42
# pylint: disable=wrong-import-order, wrong-import-position
from typing import (
Generic,
TypeVar,
)
TypeT = TypeVar('TypeT')
class Cls(Generic[TypeT]):
""" Simple class with slots """
__slots__ = ['value']
def __init__(self, value):
self.value = value
class ClassDefiningSetattr:
__slots__ = ["foobar"]
def __init__(self):
self.foobar = {}
def __setattr__(self, name, value):
if name == "foobar":
super().__setattr__(name, value)
else:
self.foobar[name] = value
class ClassWithParentDefiningSetattr(ClassDefiningSetattr):
__slots__ = []
def dont_emit_for_defined_setattr():
inst = ClassDefiningSetattr()
# This should not emit because we can't reason about what happens with
# classes defining __setattr__
inst.non_existent = "non-existent"
child = ClassWithParentDefiningSetattr()
child.non_existent = "non-existent"
class ColorCls:
__slots__ = ()
COLOR = "red"
class Child(ColorCls):
__slots__ = ()
repro = Child()
Child.COLOR = "blue"
class MyDescriptor:
"""Basic descriptor."""
def __get__(self, instance, owner):
return 42
def __set__(self, instance, value):
pass
# Regression test from https://github.com/pylint-dev/pylint/issues/6001
class Base:
__slots__ = ()
attr2 = MyDescriptor()
class Repro(Base):
__slots__ = ()
repro = Repro()
repro.attr2 = "anything"
|
