useless-with-lock / W2101

Message emitted:

'%s()' directly created in 'with' has no effect

Description:

Used when a new lock instance is created by using with statement which has no effect. Instead, an existing instance should be used to acquire lock.

Problematic code:

import threading

with threading.Lock():  # [useless-with-lock]
    print("Make your bed.")
with threading.Lock():  # [useless-with-lock]
    print("Sleep in it")

Correct code:

import threading

lock = threading.Lock()
with lock:
    print("Make your bed.")
with lock:
    print("Sleep in it.")

Created by the threading checker.