Detect global in strict mode and WebWorkers

[megawac]

fixes #2152

[michaelficarra]

It bothers me that the only detection we do now is via de facto self-references on the global object. I wish there was a more reliable way to do this, though at the same time I don't want it to be possible to get a reference to the global object in strict mode.

[michaelficarra]

self.Object == Object would be better as self.self === self.

[megawac]

Good call

[jridgewell]

I'm not entirely sure how to test, but what are self and global in ES6 modules? I assume they're either the browser's window or node's global and the only difference is the context of the module is undefined instead of one of those?

[megawac]

Yeah this will be undefined so instead we detect the global scope variable, as you mentioned self in the browser & global in node. I think your fix would work as well root = this || {}

[michaelficarra]

@megawac no, I believe this will be a ReferenceError.

[jridgewell]

👍. We should also apply this to Backbone.

[jashkenas]

I've just fixed this in Backbone like so (a little looser): jashkenas/backbone@5a6ffcb

Any objections?

[jridgewell]

It probably won't hurt much in Backbone, but avoiding self will prevent underscore from working in WebWorkers.

workers run in another global context that is different from the current window. Thus, using the window shortcut to get the current global scope (instead of self) within a Worker will return an error. - MDN

[jridgewell]

Merging in light of jashkenas/backbone#3602.

[megawac]

@jashkenas may justify a patch release

On Thu, May 14, 2015 at 12:02 PM, Justin Ridgewell <notifications@github.com

wrote:

Merged #2153 #2153.

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Reply to this email directly or view it on GitHub
#2153 (comment).

[zertosh]

I would like to point out that if you use a build tool like browserify, a reference to global, causes the module to be wrapped in:

(function (global){
/** your original module **/
}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})

I'm only pointing this out for the benefit of those that use browserify and wonder why underscore gets that wrapper. I'm not suggesting to build underscore with browserify, and I'm not suggesting this is a bad change.

[dcocchia]

This fix was merged with master in May, 2015. Almost 2 years later, can we release a patch?

[Kosta-Github]

I second the request from @dcocchia ? can you distribute the fix as a new release, please?