Fix illegal invocation errors

[jhnns]

Fixes #46

I can also confirm the fix in my local setup.

[developit]

Seems to work if you just do typeof fetch=='function' ? fetch.bind() : - thoughts?

[jhnns]

Haha nice one! 👍

[balloob]

This doesn't fix it for me. Changing it to fetch.bind(window) does work.

@developit would you be open for a PR that changes it to explicitly bind it to window?

[balloob]

Never mind. It is possible to fix it in the Webpack config without updating unfetch. Add this to your Webpack config (source):

{
  …,
  module: {
    strictThisContextOnImports: true,
  },
  …
}

[developit]

How are you testing that it didn't work @balloob?

[balloob]

Sorry, it's in a private repo at work so don't have a minimal work around. Was using Webpack 3.1 and Unfetch 3.0. When I changed bind() to bind(window) I would not get the invocation error.

Can take a stab on Monday to get a minimal repro.

[developit]

That would be good - I was testing in Safari and .bind() was working. Perhaps it's not in another browser?

[balloob]

I was testing it in Chrome.

[aga5tya]

@developit @balloob I'm using isomorphic-unfetch, confirming that i still get this error on chrome.

Edit: works just fine on safari.

[developit]

Hmm - can you try this in your console and tell me if it fails?

let unfetch = fetch.bind();
unfetch('/').then(console.log)

Works for me in Chrome 59+

[aga5tya]

@developit No errors when i run the snippet in chrome console. As @balloob was mentioning, issue happens within the app only when i bundle with webpack 3.1 and run the app on chrome. Fyi I'm on chrome 60 beta version.

[developit]

One thing I just thought of - Function.prototype.bind is IE9+