Support Webpack v4

[mtraynham]

I'm getting the following error:

ERROR in ./src/utils/404/404.extract.html
Module build failed: TypeError: Cannot read property 'output' of undefined
    at Object.extractLoader (./node_modules/extract-loader/src/extractLoader.js:31:72)
 @ ./src/utils/404/404.component.ts 18:15-44
 @ ./src/app/index.routing.ts
 @ ./src/app/index.module.ts
 @ ./src/main.ts

This points to the line https://github.com/peerigon/extract-loader/blob/master/src/extractLoader.js#L31, which seems this.options.output is no longer defined.

According to the v4 migration guide (here), this.options has been removed. Instead of loader-utils and checking this.options, you now get all options from this.query. Although, I'm not sure if that carries the publicPath option set by the webpack config. Also not sure what that publicPath's intended usage is here within the context of extract-loader. Setting it to null worked for me.

[vhmth]

This fails in v3 (3.9.1) as well. Setting to options: { publicPath: null } worked too!

[danielmeneses]

@mtraynham you are right that solves partially, but I had to set "publicPath" as an empty string otherwise it will concat "null" to all paths if you are using "html-loader" to process paths from lets say "img:src".

[jhnns]

Thanks for pointing out 👍. We're about to ship a fix for this, see PR.

[vhmth]

🎉