Make extract-text-webpack-plugin re-entrant

[andreypopp]

I'm working on React Style (see experimental branch and also #8 is slightly related as I iterated form your suggestion).

TL;DR: it produces CSS from JS:

var ReactStyle = require('react-style')

var style = ReactStyle({
  color: 'red',
  backgroundColor: 'white'
})

Becomes:

.automatically_generated_class_name {
  color: 'red';
  background-color: 'white';
}

.
The problem arises when I use both css-loader and react-style-loader with extract-text-webpack-plugin (I need to combine both approaches b/c some legacy styles I still want to import via CSS modules, like bootstrap for example).

Because plugin compiles mini-bundle which includes all JS code (due to react-style-loader) it encounters css requires once more but b/c child compiler has no extract-text-webpack-plugin configured for itself but inherits all loaders from main compiler it fails. But more importantly I don't want to process CSS files during react style bundle compilation b/c such CSS files will be processed by another child compiler (a direct child of main compiler).

So my question is how to make/configure extract-text-webpack-plugin re-entrant so child compilers don't produce another child compilers.

[sokra]

Try this:

At this line add something like:

    childCompiler.plugin("this-compilation", function(compilation) {
        childCompiler.plugin("normal-module-loader", function(loaderContext, module) {
            loaderContext[__dirname] = false;
        });
    });

and at this line add something like:

if(this[__dirname] === false) {
  return "";
} else 

So it generate an empty module for nested appliance of the extract-text-plugin loader.

[andreypopp]

@sokra thank you, this works, I initially fixed it by checking for this[__dirname] === undefined but setting explicitly false makes it more robust.

[sokra]

The check this[__dirname] === undefined may be useful too to indicate that the user forgot the add the plugin to the plugins array. Could you add an exception for this case to your PR?

[andreypopp]

@sokra added

[andreypopp]

Would be nice to have a release of the plugin after this PR is merged!