Storybook doesn't expect Webpack configs could have an array of loader's tests

[sebas5384]

In the case you have a custom Webpack configs with a test array instead of one regex, for example:

{
        test: [/react-widgets\.css$/, /outdated.css$/],
        loader: ExtractTextPlugin.extract('style-loader', 'css-loader?modules&importLoaders=1&localIdentName=[local]!postcss-loader')
},

Storybook is giving a Type error:

/Users/sebas/mywebapp/node_modules/@kadira/storybook/dist/server/config.js:101
    return value || loader.test.test('my_package.json');
                                ^

TypeError: loader.test.test is not a function

We did a workaround to solve this for now, adding the Json loader as the first module loader:

  module: {
    loaders: [
      { test: /\.json$/, loader: 'json' },

I consider it as a bug.

Cheers.