invalid-formatter-suppression-comment (RUF028)

Fix is always available.

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

What it does

Checks for formatter suppression comments that are ineffective or incompatible with Ruff's formatter.

Why is this bad?

Suppression comments that do not actually prevent formatting could cause unintended changes when the formatter is run.

Example

In the following example, all suppression comments would cause a rule violation.

def decorator():
    pass


@decorator
# fmt: off
def example():
    if True:
        # fmt: skip
        expression = [
            # fmt: off
            1,
            2,
        ]
        # yapf: disable
    # fmt: on
    # yapf: enable

Fix safety

This fix is always marked as unsafe because it deletes the invalid suppression comment, rather than trying to move it to a valid position, which the user more likely intended.