It's possible that this is already working, because Babel uses this runner and collects a coverage when running it's tests: https://github.com/babel/babel/runs/5789483528. If it already works great, I just need to document it.

It's also possible that it's only working partially, or that it's not working at all and that Babel's coverage reporting is based on something else.

(cc @psychobolt - jestjs/jest#9430 (comment))