fix(addStyles): use typeof to check for existence of window && document objects

[bherila]

What kind of change does this PR introduce?

Fixes the following error which occurs during Webpack build by adding the check via the typeof operator.

        return window && document && document.all && !window.atob;
               ^

ReferenceError: window is not defined
    at C:\Users\ucadmin\Documents\uc\admin\build\server.js:32858:9

Did you add tests for your changes?
n/a

If relevant, did you update the README?
n/a

Summary

Of note, other places in this file use the typeof operator, but curiously it is not done here.

Does this PR introduce a breaking change?
No

Other information
n/a, it's a one-liner 😄

[jsf-clabot]

All committers have signed the CLA.

[bherila]

FYI this is in addition to #177 which curiously is not enough 😦

[michael-ciniawsky]

@bherila In which exact enviroment do you use the loader (JSDOM) ?

[bebraw]

Seems sane to me. Maybe it's better to push the check to one place, though, and use it across the codebase, though?

[alexander-akait]

@bherila can your provide use case, where your need this check? best - create test repo

[bherila]

@michael-ciniawsky It was in my attempt to get https://github.com/barbar/vortigern working with bootstrap-loader (bootstrap 4). I have been attempting to get bootstrap 4 rendering with isomorphic-style-loader, and ideally have the bootstrap 4 critical path CSS analyzed and rendered server-side. As you can see from the vortigern site, there are a lot of packages being assembled together here :-\

Also, I would have shared the repo in which this reproduces, however it's for a client and I am not sure I can publish all the code on Github. I can try to make a minimal repro-repo if it would be helpful somehow. It's basically the stock vortigern + a few source files + bootstrap-loader.

[veeramarni]

any update on merging this issue.

[michael-ciniawsky]

@veeramarni Could you describe your 'use case' ? Why/Where are the current checks insufficient?

⚠️ I'm inclined to close this PR within the next 48 hours in case no concrete reproduction is provided

[veeramarni]

@michael-ciniawsky I still see those errors when running with SSR. In my case, we use webpack to create npm packages and we use these packages in an application where we get window is not defined error when we try to run with SSR. This could be due to the packaged webpack build has the style-loader.

[michael-ciniawsky]

SSR isn't officially supported, this loader only works in the browser or browser-like env like JSDOM.

we get window is not defined

Would this PR resolve your issue ?

[veeramarni]

I will give a try with this PR and let you know.