[Doc] fix tree shaking when build site

build/webpack.dev.js

@@ -49,6 +49,7 @@ module.exports = {
       },
       {
         test: /\.less$/,
+        sideEffects: true,
         use: [
           'style-loader',
           'css-loader',
@@ -63,10 +64,7 @@ module.exports = {
       },
       {
         test: /\.md$/,
-        use: [
-          'vue-loader',
-          '@vant/markdown-loader'
-        ]
+        use: ['vue-loader', '@vant/markdown-loader']
       },
       {
         test: /\.(ttf|svg)$/,

docs/src/router.js

@@ -3,7 +3,9 @@ import docConfig from './doc.config';
 import DemoList from './components/DemoList';
 import DemoPages from './components/DemoPages';
 import { demoWrapper } from './demo-common';
-import './utils/iframe-router';
+import { initIframeRouter } from './utils/iframe-router';
+
+initIframeRouter();
 
 const registerRoute = ({ mobile, componentMap }) => {
   const route = [

docs/src/utils/iframe-router.js

@@ -5,6 +5,7 @@
 import { setLang } from './lang';
 import { iframeReady, isMobile } from '.';
 
+export function initIframeRouter() {
   window.syncPath = function () {
     const router = window.vueRouter;
     const isInIframe = window !== window.top;
@@ -32,3 +33,4 @@ window.changePath = function (lang, path = '') {
     setLang(lang);
     window.vueRouter.replace(path);
   };
+}