From 7d34f2ef26b1423c89ed041094d97130da0f1987 Mon Sep 17 00:00:00 2001
From: Clark Du <clark.duxin@gmail.com>
Date: Sun, 4 Nov 2018 14:47:56 +0000
Subject: [PATCH] refactor: persist isModernBrowser on http connection (#4268)

---
 packages/vue-renderer/src/renderer.js | 16 +++++++++-------
 scripts/dev                           |  2 +-
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/packages/vue-renderer/src/renderer.js b/packages/vue-renderer/src/renderer.js
index 8a07029919..10a3bf93af 100644
--- a/packages/vue-renderer/src/renderer.js
+++ b/packages/vue-renderer/src/renderer.js
@@ -224,16 +224,18 @@ export default class VueRenderer {
       return { html, getPreloadFiles }
     }
 
-    const { req } = context
-    const ua = req && req.headers && req.headers['user-agent']
-    const isModernBrowser = this.renderer.modern && ua && matchesUA(ua, {
-      allowHigherVersions: true,
-      browsers: this.modernBrowsers
-    })
+    const { req: { socket = {}, headers } = {} } = context
+    if (socket.isModernBrowser === undefined) {
+      const ua = headers && headers['user-agent']
+      socket.isModernBrowser = this.renderer.modern && ua && matchesUA(ua, {
+        allowHigherVersions: true,
+        browsers: this.modernBrowsers
+      })
+    }
 
     let APP
     // Call renderToString from the bundleRenderer and generate the HTML (will update the context as well)
-    if (isModernBrowser) {
+    if (socket.isModernBrowser) {
       APP = await this.renderer.modern.renderToString(context)
     } else {
       APP = await this.renderer.ssr.renderToString(context)
diff --git a/scripts/dev b/scripts/dev
index 23a7898816..ff8d204b4f 100755
--- a/scripts/dev
+++ b/scripts/dev
@@ -23,7 +23,7 @@ const _require = esm(module, {
 })
 
 module.exports = _require('../src/index')
-`}
+` }
 
 async function main() {
   // Read package at current directory