use bundle analyzer plugin to analyze budle size

build/webpack.build.js

@@ -1,6 +1,7 @@
 const webpack = require('webpack');
 const config = require('./webpack.config.dev.js');
-const isMinify = process.argv.indexOf('-p') !== -1;
+const isMinify = process.argv.indexOf('-p') !== -1; 
+const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;
 
 config.entry = {
   'vant': './packages/index.js'
@@ -39,6 +40,11 @@ config.plugins = [
   new webpack.optimize.ModuleConcatenationPlugin()
 ];
 
+// analyze bundle size if need
+// if (isMinify) {
+//   config.plugins.push(new BundleAnalyzerPlugin());
+// }
+
 delete config.devtool;
 
 module.exports = config;

build/webpack.config.prod.js

@@ -1,7 +1,7 @@
-var webpack = require('webpack');
-var merge = require('webpack-merge');
-var path = require('path');
-var devConfig = require('./webpack.config.dev.js');
+const webpack = require('webpack');
+const merge = require('webpack-merge');
+const path = require('path');
+const devConfig = require('./webpack.config.dev.js');
 
 module.exports = merge(devConfig, {
   output: {