Per the ack documentation:
-g PATTERN Print files where the relative path + filename matches PATTERN. This option can be combined with --color to make it easier to spot the match.
I've searched the documentation and can't find this feature. Is this something that you'd be interested in for ripgrep? I'd be happy to submit a PR for it - I'm not a Rust expert but would love to jump in.
Thanks for writing such a great search tool!