Started using babel-preset-latest

[kripod]

No description provided.

[gaearon]

What about async/await? Do we have the right combination of plugins for it after this change?

[kripod]

According to the source code of babel-preset-es2017, it transforms async/await to generators using babel-plugin-transform-async-to-generator. After that, create-react-app can polyfill generators by babel-plugin-transform-runtime, see config/babel.dev.js and config/babel.prod.js.

[gaearon]

This probably means babel-plugin-syntax-async-functions is no longer needed?

[kripod]

Yes, because a Babel transform enables the corresponding syntax plugin.

[gaearon]

latest also contains transform-async-to-generator via 2017.
Do we still need the regenerator transform for async/await in this case?
What is the best way to enable both generators and async/await?

[kripod]

According to the documentation of babel-plugin-transform-regenerator, there are 3 regenerator transform options available: asyncGenerators, generators and async. I think that async should be set to false, but to be honest, I have no idea whether the value of asyncGenerators should be set to true or false. Maintainers of Babel may be able to help explaining the correct approach.

[kripod]

It looks like the term "async generator" may refer to an old proposal, so it could possibly be left untouched.

[gaearon]

Thanks!

[tabrezm]

Sorry in advance for digging up an old PR, but there's a lot of context here about a particular change in .babelrc that caught my eye, specifically this. I was trying to understand the combination of transforms for async, and I came across this in babel-preset-es2015.

With the preset already setting async and asyncGenerators to false, do we really need to set it ourselves in babel-preset-react-app?

[gaearon]

To be honest I don't remember. If this is still relevant can you file an issue?