not compatible with UglifyJs? about unfetch HOT 6 CLOSED

I encountered this too. Looks like it happens because:

1. Webpack resolves unfetch/polyfill to unfetch/polyfill/polyfill.mjs.
2. This file requires src/index.js which contains an ES6 arrow function
3. UglifyJs throws an error because it's expecting ES5.

A workaround is to change import 'unfetch/polyfill' to import 'unfetch/polyfill/index'.

@developit I'm not exactly sure what the purpose of polyfill/polyfill.mjs is but it seems to me that it should probably be requiring the compiled polyfill/index.js rather than the raw src/index.mjs?

from unfetch.

Same error from [email protected]

1. unfetch 4.0.1, import 'unfetch/polyfill'
   error: Invalid assignment from UglifyJs

2. unfetch 3.1.2, import 'unfetch/polyfill'
   no error

3. unfetch 4.0.1, import 'unfetch/polyfill/index.js'
   no error

4. import 'whatwg-fetch';
   no error

--
[email protected], [email protected]

from unfetch.

How did you add Unfetch (what's your import statement), and what version? It's ES3, so it shouldn't have any issues with Uglify.

Also, are you sure you're not running Uglify twice? Minification is built-in in Webpack 4+ and triggered by mode:'production'. If you're adding UglifyJsPlugin() and using mode:production, you're running two different versions of uglify back to back.

from unfetch.

Imported like so: import 'unfetch/polyfill'; at the top of my entry-file. Installed it right before I reported the issue (replacing whatwg-fetch) so it should’ve been the latest I guess.

I’m using UglifyJs plugin in optimization because I also use CSS-minification - so I dont think it should run twice.

from unfetch.

Looks like this may be related to .mjs, which shipped in Unfetch@4.

from unfetch.

The fix for this was released in 4.2.0.

from unfetch.