feat: fix test and names

src/index.js

@@ -372,9 +372,9 @@ class MiniCssExtractPlugin {
   }
 
   getFilename(chunk, filename) {
-    return this.isFunction(filename)
-      ? filename(chunk.chunk || chunk)
-      : filename;
+    console.log('--chunk--');
+    console.log(chunk);
+    return this.isFunction(filename) ? filename(chunk) : filename;
   }
 
   isFunction(functionToCheck) {

test/cases/filename-function/webpack.config.js

@@ -18,8 +18,8 @@ module.exports = {
   },
   plugins: [
     new Self({
-      filename: (data) => data.chunk.name == 'app' ? 'this.is.app.css' : `[name].css`,
-      chunkFilename: (data) => '[name].css',
+      filename: (chunk) => chunk.name == 'app' ? 'this.is.app.css' : `[name].css`,
+      chunkFilename: (chunk) => '[name].css',
     }),
   ],
 };