redundant-literal-union (PYI051)

Added in v0.0.283 · Related issues · View source

Derived from the flake8-pyi linter.

What it does

Checks for redundant unions between a Literal and a builtin supertype of that Literal.

Why is this bad?

Using a Literal type in a union with its builtin supertype is redundant, as the supertype will be strictly more general than the Literal type. For example, Literal["A"] | str is equivalent to str, and Literal[1] | int is equivalent to int, as str and int are the supertypes of "A" and 1 respectively.

Example

from typing import Literal

x: Literal["A", b"B"] | str

Use instead:

from typing import Literal

x: Literal[b"B"] | str