* add tests but not baselines or fixes
* Update original change
Still probably wrong; probably doesn't even compile beacuse I'm just
typing on my laptop.
* fix error code ok
* notes to self
* Error: property is specified more than once via spread
* make jsx tests stricter
* update semicolon error message
* use ?. because it is great
* use maybeTypeOfKind in new code
* restore jsx error
* add tests