"Coverage report generated" is being written to the stdout stream

[nevinera]

Hello! We're writing a tool that runs other tools, rspec among them. One of the problems we've been running into though, is that a ton of people use simplecov already, and when you run rspec -f json, simplecov still writes its "Coverage report generated" message to stdout in plaintext to the same stream.

This seems to be the intent, based on some feature specs I see (like this one), but is there any particular reason to write this to stdout instead of stderr? This seems more like progress/outcome logging than results data (though I recognize the awkwardness of exposing any kind of results when you're essentially a hitchhiker on somebody else's process).

This is somewhat related to #992, though any solution to that (and the workaround described) would need to be invoked by the project intentionally (and so probably wouldn't suffice for our particular intentions).

I'd be happy to contribute a pull-request for this, if you think it's a viable/allowable change to make. Though I might need a pointer, since I'm having trouble figuring out where that text is actually coming from in the gem source :-)

Edit: Found it, it's happening in simplecov-html's HTMLFormatter apparently. No releases there since 2020 - should I bother with a pair of PRs for this?

(I'm using Simplecov 0.22.0 to produce the observed behavior, but I've seen it in a number of prior versions)