added ES6 support with babel

[janza]

This pull request adds support for babel transpiler for javascript.
It adds support for ES6/7 features in files with .es extension.

[sintaxi]

oh wow, this would be nice.

Is the .es extension an existing convention?

[janza]

I've seen it listed as supported extension in babel alogside .es6 and .js.
I think that it's better to have a separate extension for this (than to parse every .js file in the directory).

[zeke]

cool beans

[janza]

Is there a plan to merge this? Anything missing?

[kennethormandy]

Time to properly review it mainly :)

We haven’t forgotten about it, but it probably won’t be in the next release (which might be #94). We’d still need to write docs too.

Definitely appreciate the hard work that has gone into this, so thank you!

[janza]

Awesome, thanks!

[jdcauley]

Anything I can do to help move this along, would be very interested in this feature.

Happy to help with docs or something.

[kennethormandy]

I think we would need to:

• Make sure @sintaxi wants it merged
• Merge the Browserify stuff first Added support for Browserify #97 Ko browserify js #98 using .js as the extension instead of .es (this requires a change in Harp since .html, .css, and .js were always omitted from preprocessing before
• Decide on an extension (.es makes sense to me, but I don’t know the Babel/ES6/ES2015/whatever conventions well)
• Add docs, the CoffeeScript page could be used as a starting point, although those are quite sparse as well

[phated]

The defacto standard (because of the interpret module used by gulp/webpack/etc) is .babel.js

[kennethormandy]

Thanks Blaine. That makes it kind of a confusing choice since we do .[output].[input] for the asset pipeline, ex. .xml.jade. So .js.babel would actually be the “correct” choice, with Harp’s current conventions.

I supposed in this case Babel is drawing from .min.js? We could just do .babel but then I guess everyone would still have to re-name things they were porting, which kind of defeats the purpose of trying to conform to existing conventions at all.

[phated]

@kennethormandy I think .js.babel could work. We had a long discussion at gulpjs/gulp#830 and determined that making the extension contain which transpiler made more sense than a generic .es or .es6 extension because there is more than 1 transpiler and they handle things differently

[sintaxi]

@jdcauley thanks for asking.

I want this in. I just want to make sure we keep CommonJS a high priority. Also, anything that works in JS ideally also works within coffeescript files. Perhaps that is less of a priority if we go with another extension such as .es.

[ir-g]

@sintaxi Is this going into the next release?

[Ore4444]

+1 please

[og2t]

+1

[danguilherme]

Manually doing a 👍 here.

[eapostol]

Anything new on this thread regarding ES6 support in Harp?