Backbone no longer works w/ Ender (Backbone.$ not set when exports is defined)

[symmetriq]

I use Backbone as a module in some of my Ender-built libraries. As of Backbone 1.1.1, the Backbone.$ reference is now undefined instead of pointing at the global $. I assume there's a valid reason to omit $ in some situations, but in this case it prevents Backbone from working as an Ender module.

Because exports always exists when modules are part of an Ender library, $ doesn't get passed to factory:

// Next for Node.js or CommonJS. jQuery may not be needed as a module.
} else if (typeof exports !== 'undefined') {
  var _ = require('underscore');
  factory(root, exports, _);

This is where we really need to end up, but it's now unreachable in the context of an Ender library:

// Finally, as a browser global.
} else {
  root.Backbone = factory(root, {}, root._, (root.jQuery || root.Zepto || root.ender || root.$));
}

[tgriesser]

Yep, this was brought up in a few other tickets (see the end of #2997).

The solution is to do:

Backbone.$ = $;

wherever Backbone is first referenced.

[symmetriq]

Yeah, I actually tried that. The trouble is, due to the way Ender modules are created, there's no way to add that reference without losing the ability to integrate Backbone into $. Ender integrates modules' methods into $ via $.ender(require('module_name')). If I attempt to add the $ reference first (e.g. like below), it results in an infinite loop (until the max stack size limit is reached), presumably due to a circular reference somewhere:

$.ender((function () {
  var b = require('backbone');
  b.$ = $;
  return b;
}()));

I've managed to work around this by just not integrating Backbone into $ (which means one more global variable) and updating all references to Backbone methods, but I'm wondering what was gained by breaking this usage pattern?

At the very least, the root.ender reference might as well be removed from the latter block in my first post, since that block is now unreachable when Backbone is part of an Ender library.

[jashkenas]

@symmetriq Would you like to send in a patch that fixes the Ender loading problem? Is such a patch possible?

[symmetriq]

@jashkenas Done: #3038

[akre54]

closing in favor of #3038.