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# pylint: disable=missing-docstring, missing-module-docstring, invalid-name
# pylint: disable=too-few-public-methods, line-too-long, dangerous-default-value
# pylint: disable=wrong-import-order
# https://github.com/PyCQA/pylint/issues/4774
def github_issue_4774():
# Test literals
# https://github.com/PyCQA/pylint/issues/4774
good_list = []
if not good_list:
pass
bad_list = []
if bad_list == []: # [use-implicit-booleaness-not-comparison]
pass
# Testing for empty literals
empty_tuple = ()
empty_list = []
empty_dict = {}
if empty_tuple == (): # [use-implicit-booleaness-not-comparison]
pass
if empty_list == []: # [use-implicit-booleaness-not-comparison]
pass
if empty_dict == {}: # [use-implicit-booleaness-not-comparison]
pass
if () == empty_tuple: # [use-implicit-booleaness-not-comparison]
pass
if [] == empty_list: # [use-implicit-booleaness-not-comparison]
pass
if {} == empty_dict: # [use-implicit-booleaness-not-comparison]
pass
def bad_tuple_return():
t = (1, )
return t == () # [use-implicit-booleaness-not-comparison]
def bad_list_return():
b = [1]
return b == [] # [use-implicit-booleaness-not-comparison]
def bad_dict_return():
c = {1: 1}
return c == {} # [use-implicit-booleaness-not-comparison]
assert () == empty_tuple # [use-implicit-booleaness-not-comparison]
assert [] == empty_list # [use-implicit-booleaness-not-comparison]
assert {} != empty_dict # [use-implicit-booleaness-not-comparison]
assert () < empty_tuple # [use-implicit-booleaness-not-comparison]
assert [] <= empty_list # [use-implicit-booleaness-not-comparison]
assert () > empty_tuple # [use-implicit-booleaness-not-comparison]
assert [] >= empty_list # [use-implicit-booleaness-not-comparison]
assert [] == []
assert {} != {}
assert () == ()
d = {}
if d in {}:
pass
class NoBool:
def __init__(self):
self.a = 2
class YesBool:
def __init__(self):
self.a = True
def __bool__(self):
return self.a
# Should be triggered
a = NoBool()
if [] == a: # [use-implicit-booleaness-not-comparison]
pass
a = YesBool()
if a == []:
pass
# compound test cases
e = []
f = {}
if e == [] and f == {}: # [use-implicit-booleaness-not-comparison, use-implicit-booleaness-not-comparison]
pass
named_fields = [0, "", "42", "forty two"]
empty = any(field == "" for field in named_fields)
something_else = NoBool()
empty_literals = [[], {}, ()]
is_empty = any(field == something_else for field in empty_literals)
h, i, j = 1, None, [1,2,3]
def test(k):
print(k == {})
def test_with_default(k={}):
print(k == {})
print(k == 1)
test(h)
test(i)
test(j)
test_with_default(h)
test_with_default(i)
test_with_default(j)
class A:
lst = []
@staticmethod
def test(b=1):
print(b)
return []
if A.lst == []: # [use-implicit-booleaness-not-comparison]
pass
if [] == A.lst: # [use-implicit-booleaness-not-comparison]
pass
if A.test("b") == []: # [use-implicit-booleaness-not-comparison]
pass
def test_function():
return []
if test_function() == []: # [use-implicit-booleaness-not-comparison]
pass
# pylint: disable=import-outside-toplevel, wrong-import-position, import-error
# Numpy has its own implementation of __bool__, but base class has list, that's why the comparison check is happening
import numpy
numpy_array = numpy.array([0])
if numpy_array == []: # [use-implicit-booleaness-not-comparison]
print('numpy_array')
if numpy_array != []: # [use-implicit-booleaness-not-comparison]
print('numpy_array')
if numpy_array >= (): # [use-implicit-booleaness-not-comparison]
print('b')
# pandas has its own implementations of __bool__ and is not subclass of list, dict, or tuple; that's why comparison check is not happening
import pandas as pd
pandas_df = pd.DataFrame()
if pandas_df == []:
pass
if pandas_df != ():
pass
if pandas_df <= []:
print("don't emit warning if variable can't safely be inferred")
from typing import Union
from random import random
var: Union[dict, bool, None] = {}
if random() > 0.5:
var = True
if var == {}:
pass
data = {}
if data == {}: # [use-implicit-booleaness-not-comparison]
print("This will be printed")
if data != {}: # [use-implicit-booleaness-not-comparison]
print("This will also be printed")
if data or not data:
print("This however won't be")
# literal string check
long_test = {}
if long_test == { }: # [use-implicit-booleaness-not-comparison]
pass
# Check for properties and uninferable class methods
# See https://github.com/PyCQA/pylint/issues/5646
from xyz import AnotherClassWithProperty
class ParentWithProperty:
@classmethod
@property
def parent_function(cls):
return {}
class MyClassWithProxy(ParentWithProperty):
attribute = True
@property
@classmethod
def my_property(cls):
return {}
@property
@classmethod
def my_difficult_property(cls):
if cls.attribute:
return {}
return MyClassWithProxy()
def test_func():
"""Some assertions against empty dicts."""
my_class = MyClassWithProxy()
assert my_class.parent_function == {} # [use-implicit-booleaness-not-comparison]
assert my_class.my_property == {} # [use-implicit-booleaness-not-comparison]
# If the return value is not always implicit boolean, don't raise
assert my_class.my_difficult_property == {}
# Uninferable does not raise
assert AnotherClassWithProperty().my_property == {}
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