Parse number for importLoaders in query parameter

[cdoublev]

Following your instructions given in this issue...

• Operating System: Debian Buster
• Node Version: 14.7.0
• NPM Version: 6.14.7
• webpack Version: 4.44.1
• css-loader Version: 4.2.1

Expected Behavior / Situation

Run webpack with the following configuration, ie. containing an inline - string - definition of css-loader that contains number as value for importLoaders:

module.exports = {
    // ...
    module: { rules: [{
        test: /\.css$/,
        use: ['style-loader', 'css-loader?importLoaders=1', 'postcss-loader'],
    }] },
    // ...

Actual Behavior / Situation

Error thrown:

ValidationError: Invalid options object. CSS Loader has been initialized using an options object that does not match the API schema.
 - options.importLoaders should be one of these:
   boolean | integer
   -> Enables/Disables or setups number of loaders applied before CSS loader (https://github.com/webpack-contrib/css-loader#importloaders).
   Details:
    * options.importLoaders should be a boolean.
    * options.importLoaders should be a integer.

Modification Proposal

css-loader/src/options.json

Line 133 in 8353353

"importLoaders": {

 // ...
         {
           "type": "integer"
+        },
+        {
+          "type": "string"
         }
       ]
     },
 // ...

css-loader/src/utils.js

Line 225 in 8353353

importLoaders: rawOptions.importLoaders,

     : loaderContext.sourceMap,
-    importLoaders: rawOptions.importLoaders,
+   importLoaders: parseInt(rawOptions.importLoaders),
     esModule:
       typeof rawOptions.esModule === 'undefined' ? true : rawOptions.esModule,
   };

[alexander-akait]

css-loader?importLoaders=1 was deprecated in webpack@5 and will not work, anyway I can support is for query options