Write tests for Test262

[jugglinmike]

This proposal will need tests in Test262 in order to advance to stage 4 of TC39's proposal process.

I'd be happy to take a shot at this--let me know!

[jugglinmike]

I'm still interested in helping out, but I don't want to step on anyone's toes. @rbuckton could you use a hand? Do you have a time frame in mind?

[rbuckton]

You are welcome to, if you'd like. I'm currently heads down on prepping for the TypeScript 4.3 beta and likely won't have a chance to look at this for another week.

[jugglinmike]

Here's a patch! tc39/test262#2968

[Kingwl]

May pay some attention on #43 too.😂