regex-flag-alias (FURB167)

Derived from the refurb linter.

Fix is always available.

This rule is unstable and in preview. The --preview flag is required for use.

What it does

Checks for the use of shorthand aliases for regular expression flags (e.g., re.I instead of re.IGNORECASE).

Why is this bad?

The regular expression module provides descriptive names for each flag, along with single-letter aliases. Prefer the descriptive names, as they are more readable and self-documenting.

Example

import re

if re.match("^hello", "hello world", re.I):
    ...

Use instead:

import re

if re.match("^hello", "hello world", re.IGNORECASE):
    ...