Is any ECMAScript code valid code also valid uwu code?
No. uwu comes with certain intentional syntax restrictions that are reported by the scanner. However, any uwu script is valid JS code.
See SYNTAX.md.
How do I migrate exisiting SmartWeave contracts to uwu?
If your contract source follows the syntax guidlines, you don't need to do anything to migrate.
Run
uwu-clion your exisitng contract to see all diagnostics.
This part of the doc is still a WIP.