stop-iteration-return (PLR1708)

Derived from the Pylint linter.

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

What it does

Checks for explicit raise StopIteration in generator functions.

Raising StopIteration in a generator function causes a RuntimeError when the generator is iterated over.

Instead of raise StopIteration, use return in generator functions.

def my_generator():
    yield 1
    yield 2
    raise StopIteration  # This causes RuntimeError at runtime

Use instead:

def my_generator():
    yield 1
    yield 2
    return  # Use return instead