"this" should reference the window object

This a 🐛 bug report.

“this” within imported scripts references an empty object rather than the window object.

🎛 Configuration

parcel index.html

(That’s it! That’s why I love parcel!!! 😃)

🤔 Expected Behavior

The window object should be available as “this” to scripts imported via the script tag.

😯 Current Behavior

“this” references an empty object instead.

💁 Possible Solution

I haven’t had a chance to go through the source code, but I imagine that imported code is being run within with a context somewhere. We’re passing in “{}” as the context where we should pass in the window object.

Alternatively, we might pass in a parcel-specific attribute to HTML tags that would direct parcel not to run code in a different context, but execute it untouched?

<script parcel-untouched src="./external-script"></script>

🔦 Context

I’m developing packages with rollup. Creating modules that attach themselves to the window object appears to need “this” to reference the window.

This might be consider an issue with rollup, or maybe even just my configuration, but it seems entirely legitimate to develop other libraries in this way.

💻 Code Sample

external-script.js

console.log(this);

index.html (partial)

<script src="./external-script.js"></script>
<!-- logs "{}" -->
<script>
    console.log(this);
</script>
<!-- logs window object as expected-->

🌍 Your Environment

Software	Version(s)
Parcel	1.6.1
Node	9.5.0
npm/Yarn	npm 5.6.0
Operating System	Mac 10.13.3

[mischnic]

I don’t know if that would be correct, some sources:

Babel assumes that all input code is an ES2015 module. ES2015 modules are implicitly strict mode so this means that top-level this is not window in the browser nor is it exports in node. (https://babeljs.io/faq#why-is-this-being-remapped-to-undefined)

Module code is always strict mode code. (http://www.ecma-international.org/ecma-262/6.0/#sec-strict-mode-code)

That means, among other things, that in browsers it’s no longer possible to reference the window object through this inside a strict mode function. (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Strict_mode)

[github-actions[bot]]

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