WIP - add extractor, generate snippet_data

node_modules/optimize-css-assets-webpack-plugin/src/index.js

@@ -0,0 +1,83 @@
+const url = require('url');
+
+const LastCallWebpackPlugin = require('last-call-webpack-plugin');
+
+class OptimizeCssAssetsWebpackPlugin extends LastCallWebpackPlugin {
+  constructor(options) {
+    super({
+      assetProcessors: [
+        {
+          phase: LastCallWebpackPlugin.PHASES.OPTIMIZE_CHUNK_ASSETS,
+          regExp: (options && options.assetNameRegExp) || /\.css(\?.*)?$/i,
+          processor: (assetName, asset, assets) =>
+            this.processCss(assetName, asset, assets),
+        }
+      ],
+      canPrint: options && options.canPrint,
+    });
+
+    this.options.assetNameRegExp = !options || !options.assetNameRegExp ?
+      /\.css(\?.*)?$/i :
+      options.assetNameRegExp;
+    this.options.cssProcessor = !options || !options.cssProcessor ?
+        require('cssnano') :
+        options.cssProcessor;
+    this.options.cssProcessorOptions = !options || options.cssProcessorOptions === undefined ?
+      {} :
+      options.cssProcessorOptions;
+    this.options.cssProcessorPluginOptions = !options || options.cssProcessorPluginOptions === undefined ?
+      {} :
+      options.cssProcessorPluginOptions;
+  }
+
+  buildPluginDescriptor() {
+    return { name: 'OptimizeCssAssetsWebpackPlugin' };
+  }
+
+  processCss(assetName, asset, assets) {
+    const parse = url.parse(assetName);
+    const assetInfo = {
+      path: parse.pathname,
+      query: parse.query ? `?${parse.query}` : '',
+    };
+
+    const css = asset.sourceAndMap ? asset.sourceAndMap() : { source: asset.source() };
+    const processOptions = Object.assign(
+      { from: assetName, to: assetName },
+      this.options.cssProcessorOptions
+    );
+
+    if (processOptions.map && !processOptions.map.prev) {
+      try {
+        let map = css.map;
+        if (!map) {
+          const mapJson = assets.getAsset(`${assetInfo.path}.map`);
+          if (mapJson) {
+            map = JSON.parse(mapJson);
+          }
+        }
+        if (
+          map &&
+          (
+            (map.sources && map.sources.length > 0) ||
+            (map.mappings && map.mappings.length > 0)
+          )
+        ) {
+          processOptions.map = Object.assign({ prev: map }, processOptions.map);
+        }
+      } catch (err) {
+        console.warn('OptimizeCssAssetsPlugin.processCss() Error getting previous source map', err);
+      }
+    }
+    return this.options
+      .cssProcessor.process(css.source, processOptions, this.options.cssProcessorPluginOptions)
+      .then(r => {
+        if (processOptions.map && r.map && r.map.toString) {
+          assets.setAsset(`${assetInfo.path}.map${assetInfo.query}`, r.map.toString());
+        }
+        return r.css;
+      });
+  }
+}
+
+module.exports = OptimizeCssAssetsWebpackPlugin;