Uncaught ReferenceError: _this3 is not defined

[EmpireJones]

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Description

What you are reporting:
When I modify some components, I get:
Uncaught ReferenceError: _this3 is not defined

Looking at the code which is running:

(function REACT_HOT_LOADER_SANDBOX () {
          var _this = this; // common babel transpile
          var _this2 = this; // common babel transpile
          return function (props) {
		// cancel existing requests
		_this3.state.doFetchStopper && _this3.state.doFetchStopper.stop();

I agree that it looks like _this3 doesn't exist.

Based on the code in /src/proxy/inject.js, _this2 is called out explicitly; should _this3 be there too?

This seems related: babel/babel#4550
Which references this: #391
but that issues says that it's fixed in 4.0.0 (I'm using 4.0.1 of react-hot-loader).

Expected behavior

What you think should happen:
_this3 should exist?

Actual behavior

What actually happens:

_this3 doesn't exist

Environment

React Hot Loader version:

Run these commands in the project folder and fill in their results:

1. node -v: v9.10.1
2. npm -v: 5.6.0

Then, specify:

1. Operating system: Ubuntu 17.10
2. Browser and version: 65.0.3325.181 (Official Build) (64-bit)

[theKashey]

It is not easy to properly fix this, and the best way is to transpile code not into es5, but to es6. Ie keep arrow functions arrow.
(but I will add _this3)

[EmpireJones]

@theKashey - awesome, thanks! I can confirm that building without the code transpiled for older browsers fixes it. I'd prefer to have my development setup mirror production, so this change will be helpful.
Thanks again!