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# pylint: disable=too-few-public-methods,import-error, missing-docstring, misplaced-comparison-constant
# pylint: disable=useless-super-delegation,wrong-import-position,invalid-name, wrong-import-order, condition-evals-to-constant
if len('TEST'): # [len-as-condition]
pass
if not len('TEST'): # [len-as-condition]
pass
z = []
if z and len(['T', 'E', 'S', 'T']): # [len-as-condition]
pass
if True or len('TEST'): # [len-as-condition]
pass
if len('TEST') == 0: # Should be fine
pass
if len('TEST') < 1: # Should be fine
pass
if len('TEST') <= 0: # Should be fine
pass
if 1 > len('TEST'): # Should be fine
pass
if 0 >= len('TEST'): # Should be fine
pass
if z and len('TEST') == 0: # Should be fine
pass
if 0 == len('TEST') < 10: # Should be fine
pass
if 0 < 1 <= len('TEST') < 10: # Should be fine
pass
if 10 > len('TEST') != 0: # Should be fine
pass
if 10 > len('TEST') > 1 > 0: # Should be fine
pass
if 0 <= len('TEST') < 100: # Should be fine
pass
if z or 10 > len('TEST') != 0: # Should be fine
pass
if z:
pass
elif len('TEST'): # [len-as-condition]
pass
if z:
pass
elif not len('TEST'): # [len-as-condition]
pass
while len('TEST'): # [len-as-condition]
pass
while not len('TEST'): # [len-as-condition]
pass
while z and len('TEST'): # [len-as-condition]
pass
while not len('TEST') and z: # [len-as-condition]
pass
assert len('TEST') > 0 # Should be fine
x = 1 if len('TEST') != 0 else 2 # Should be fine
f_o_o = len('TEST') or 42 # Should be fine
a = x and len(x) # Should be fine
def some_func():
return len('TEST') > 0 # Should be fine
def github_issue_1325():
l = [1, 2, 3]
length = len(l) if l else 0 # Should be fine
return length
def github_issue_1331(*args):
assert False, len(args) # Should be fine
def github_issue_1331_v2(*args):
assert len(args), args # [len-as-condition]
def github_issue_1331_v3(*args):
assert len(args) or z, args # [len-as-condition]
def github_issue_1331_v4(*args):
assert z and len(args), args # [len-as-condition]
b = bool(len(z)) # [len-as-condition]
c = bool(len('TEST') or 42) # [len-as-condition]
def github_issue_1879():
class ClassWithBool(list):
def __bool__(self):
return True
class ClassWithoutBool(list):
pass
class ChildClassWithBool(ClassWithBool):
pass
class ChildClassWithoutBool(ClassWithoutBool):
pass
assert len(ClassWithBool())
assert len(ChildClassWithBool())
assert len(ClassWithoutBool()) # [len-as-condition]
assert len(ChildClassWithoutBool()) # [len-as-condition]
assert len(range(0)) # [len-as-condition]
assert len([t + 1 for t in []]) # [len-as-condition]
assert len(u + 1 for u in []) # [len-as-condition]
assert len({"1":(v + 1) for v in {}}) # [len-as-condition]
assert len(set((w + 1) for w in set())) # [len-as-condition]
# pylint: disable=import-outside-toplevel
import numpy
numpy_array = numpy.array([0])
if len(numpy_array) > 0:
print('numpy_array')
if len(numpy_array):
print('numpy_array')
if numpy_array:
print('b')
import pandas as pd
pandas_df = pd.DataFrame()
if len(pandas_df):
print("this works, but pylint tells me not to use len() without comparison")
if len(pandas_df) > 0:
print("this works and pylint likes it, but it's not the solution intended by PEP-8")
if pandas_df:
print("this does not work (truth value of dataframe is ambiguous)")
def function_returning_list(r):
if r==1:
return [1]
return [2]
def function_returning_int(r):
if r==1:
return 1
return 2
# def function_returning_generator(r):
# for i in [r, 1, 2, 3]:
# yield i
# def function_returning_comprehension(r):
# return [x+1 for x in [r, 1, 2, 3]]
# def function_returning_function(r):
# return function_returning_generator(r)
assert len(function_returning_list(z)) # [len-as-condition]
assert len(function_returning_int(z))
# This should raise a len-as-conditions once astroid can infer it
# See https://github.com/PyCQA/pylint/pull/3821#issuecomment-743771514
# assert len(function_returning_generator(z))
# assert len(function_returning_comprehension(z))
# assert len(function_returning_function(z))
def github_issue_4215():
# Test undefined variables
# https://github.com/PyCQA/pylint/issues/4215
if len(undefined_var): # [undefined-variable]
pass
if len(undefined_var2[0]): # [undefined-variable]
pass
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