feat: support object rest properties

[dariocravero]

No description provided.

[nhunzaker]

Total spectator, but 👍. I was just about to dig into this myself to iron out my final speed-bumb moving from Babel to Bublé. I'd love to see this ship!

[fatfisz]

@dariocravero Hey, when will you be able to land this? Could I help with that if you don't have time right now?

[dariocravero]

Hey @fatfisz, thanks for proposing to help :) (@nhunzaker I totally missed your comments, thanks :)) .

I think it's almost ok to go. I can't remember well but I think it's missing a few tests, I was bringing them over from babylon's.

A couple of things to note:

• because this is meant to work with acorn, this implementation differs a bit from babylon's as it doesn't replace the Property token with ObjectProperty and ObjectMethod.
• the test runner is a bit odd (it was brought over from some other acorn plugin), while it works ok, it could be greatly simplified making it easier to follow, e.g. using fixtures, may do that at some point but there are more relevant things to tackle now. Here's where the ast gets produced in the tests (it may help debugging) :).

If you could try to add the remaining tests and see what happens then, that would be amazing!
The objective of this extension was to have bublé support rest properties, you can check that out here. The parser needs to be ready for that to work though.

Thanks again,
Darío

[adrianheine]

I implemented rest properties in my fork.