an issue would be super useful, until we can hook move errors to rustc and see all that's missing, in order to check and modify all the rules at once
but this specific case might be of interest to @Albin Stjerna who worked on move errors
It's been a while, but IIRC I intentionally left this check out because I figured we might want to support partial assignments, provided they were safe, and that the more granular move analysis performed by Polonius would be enough to handle them.
Still, for checking against rustc to verify errors? Possibly a good idea