A few other rules do this too (like check_missing_colon_in_role), but take unnecessary-parenthesis as an example: because unnecessary-parenthesis runs a regex that catches a single instance, it will only catch a single instance per line.

This isn't a bug, but still makes it annoying to fix issues as things pop up one after another. Feel free to close this though.

I'd be happy to contribute this if this is something to be fixed.