Remove Babel helper binding renaming

[ericf]

The attempt to fix the Babel helper binding renaming in #31 didn't work for all cases. The transform-object-rest-spread uses:

babelHelpers['extends']

It seems safer to just remove this optimization, and let the helpers stay named babelHelpers..

[eventualbuddha]

Could we just make Babel use a more consistent format?

[ericf]

@eventualbuddha isn't it up the plugin author to determine how the helper is invoked? Or add extra helpers to the collection for their plugin?

[Victorystick]

One possible way to get the best of both worlds would be to import a virtual, ES2015 version of the babel-helpers where one or more helper are used.

import * as babelHelpers from 'babel-helpers';

// This access will be optimised automatically by Rollup.
babelHelpers.createClass(...);

// Rollup will make sure this dynamic access will work
// while preserving all other optimised accesses.
babelHelpers[ dynamic ](...);

When babel-helpers is imported, we inject a virtual module like so:

return buildExternalHelpers( all, 'var' )
  .replace( /var babelHelpers = {};\n/, '' ) // strip declaration
  .replace( /babelHelpers\.(.+) = /g, 'export var $1 = ' ) // export the helper
  .replace( 'babelHelpers;', '' ) // not sure where this comes from...
  .trim() + '\n';

Thoughts?

[ericf]

Would you guys be up for merging this to fix the immediate issue of Rollup producing code that errors when certain Babel plugins are being used? And in parallel we can get a more robust solution in place and explore ideas like @Victorystick's?

[eventualbuddha]

I'm fine with that.
On Thu, Jan 14, 2016 at 8:37 AM Eric Ferraiuolo notifications@github.com
wrote:

Would you guys be up for merging this to fix the immediate issue of Rollup
producing code that errors when certain Babel plugins are being used? And
in parallel we can get a more robust solution in place and explore ideas
like @Victorystick https://github.com/Victorystick's?

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#34 (comment)
.

[Victorystick]

@ericf Absolutely. 👍

I've just realised that we'll run into trouble with babelHelpers.typeof = ... using my approach. We cannot transform it into an exported var declaration. It'll result in a SyntaxError. If only Babel had chosen to name it typeOf instead... 😭

export var typeof = ...

export var typeOf = ...

[ericf]

@Victorystick @eventualbuddha okay great! Let me know if there's anything else I can do to help you guys get a patch release out.

[eventualbuddha]

Released in v2.3.9.

[ericf]

Thanks guys!