use-maxsplit-arg / C0207#

Message emitted:

Use %s instead

Description:

Emitted when accessing only the first or last element of str.split(). The first and last element can be accessed by using str.split(sep, maxsplit=1)[0] or str.rsplit(sep, maxsplit=1)[-1] instead.

Correct code:

url = "www.example.com"
suffix = url.rsplit(".", maxsplit=1)[-1]

Problematic code:

url = "www.example.com"
suffix = url.split(".")[-1]  # [use-maxsplit-arg]

Additional details:

Be aware that the performance improvement from not splitting the string so many times will only be realized in cases presenting more instances of the splitting character than the minimal example here.

Created by the refactoring checker.