use-is-for-singletons¶

Collection: fixit-extra Autofix: Yes Python: Any

Require identity operators when comparing singleton primitives.

Message¶

Comparisons to singleton primitives should not be done with == or !=, as they check equality rather than identity. Use is or is not instead.

if x: pass

if not x: pass

x is True

x is False

x is None

x is not None

x is True is not y

y is None is not x

None is y

True is x

False is x

x == 2

2 != x

"True" == "True"

"True" != "False".lower()

x != True

Suggested fix

x is not True

x != False

Suggested fix

x is not False

x == False

Suggested fix

x is False

x == None

Suggested fix

x is None

x != None

Suggested fix

x is not None

False == x

Suggested fix

False is x

x is True == y

Suggested fix

x is True is y