Environment

ESLint version: 8.29.0

What parser are you using?

Default (Espree)

What did you do?

module.exports = {
  reportUnusedDisableDirectives: true,
  rules: {
    'no-fallthrough': 'error',
  },
};

switch (test) {
  case a:
    hello();

  // eslint-disable-next-line no-fallthrough
  case b:
}

What did you expect to happen?

The rule report should be hidden and no "unused disable directive" warnings should be reported.

What actually happened?

An unused disable directive warning is reported

Participation

• I am willing to submit a pull request for this issue.

Additional comments

This default behaviour is problematic because if you run eslint --fix, then eslint will remove the unused disable comment, causing no-fallthrough error.

I think that this occurs because the default comment regex will match the no-fallthrough string

IMO either the rule should ignore eslint-disable directives, or the default regex should be updated to ignore them to prevent this behaviour.