ruff format a Python string

ruff_format.py

import subprocess
from pathlib import Path

# see https://github.com/astral-sh/ruff/pull/18224
from ruff.__main__ import (  # type: ignore[import-untyped]  # pyright: ignore[reportMissingTypeStubs]
    find_ruff_bin,  # noqa: PLC2701
)


def ruff_format(source: str) -> str:
    result = subprocess.run(
        [find_ruff_bin(), "format", "-"],
        input=source,
        text=True,
        capture_output=True,
        check=True,
        cwd=Path.cwd(),
    )
    result.check_returncode()
    return result.stdout

Compatible with mypy==1.15.0 and pyright==1.1.400 in strict mode.