I think the most current docs for the loader hooks are here:
https://github.com/nodejs/node/blob/master/doc/api/esm.md#loadurl-context-defaultload
In the section above in the table for formats, it has a column called
Acceptable types For source returned by resolve or load
This leads me to believe that resolve somehow would be capable of returning source but I think it is not? Is this an error in the docs or have I misunderstood something?