From cd60dc921dccd74c4d2c4e306643b3006d7b973e Mon Sep 17 00:00:00 2001
From: Alec Larson <1925840+aleclarson@users.noreply.github.com>
Date: Tue, 29 Jun 2021 22:43:35 -0400
Subject: [PATCH 1/2] fix: stop using `posix.join` on `config.base`

---
 packages/vite/src/node/plugins/clientInjections.ts     | 2 +-
 packages/vite/src/node/server/middlewares/indexHtml.ts | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/vite/src/node/plugins/clientInjections.ts b/packages/vite/src/node/plugins/clientInjections.ts
index 028537eb486f63..da3483470b9098 100644
--- a/packages/vite/src/node/plugins/clientInjections.ts
+++ b/packages/vite/src/node/plugins/clientInjections.ts
@@ -34,7 +34,7 @@ export function clientInjectionsPlugin(config: ResolvedConfig): Plugin {
         }
         let hmrBase = config.base
         if (options.path) {
-          hmrBase = path.posix.join(hmrBase, options.path)
+          hmrBase = hmrBase + options.path
         }
         if (hmrBase !== '/') {
           port = path.posix.normalize(`${port}${hmrBase}`)
diff --git a/packages/vite/src/node/server/middlewares/indexHtml.ts b/packages/vite/src/node/server/middlewares/indexHtml.ts
index 9d870fe8df8f19..968b210abe1c5e 100644
--- a/packages/vite/src/node/server/middlewares/indexHtml.ts
+++ b/packages/vite/src/node/server/middlewares/indexHtml.ts
@@ -138,7 +138,7 @@ const devHtmlHook: IndexHtmlTransformHook = async (
         tag: 'script',
         attrs: {
           type: 'module',
-          src: path.posix.join(base, CLIENT_PUBLIC_PATH)
+          src: base + CLIENT_PUBLIC_PATH.slice(1)
         },
         injectTo: 'head-prepend'
       }

From 0a2299a7d5d2ac65c36dcfbc0ca8d865aeb704ae Mon Sep 17 00:00:00 2001
From: Alec Larson <1925840+aleclarson@users.noreply.github.com>
Date: Tue, 29 Jun 2021 23:33:35 -0400
Subject: [PATCH 2/2] fix: skip HMR port suffix when `config.base` is external

---
 packages/vite/src/node/plugins/clientInjections.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/vite/src/node/plugins/clientInjections.ts b/packages/vite/src/node/plugins/clientInjections.ts
index da3483470b9098..dae99d8365e93f 100644
--- a/packages/vite/src/node/plugins/clientInjections.ts
+++ b/packages/vite/src/node/plugins/clientInjections.ts
@@ -2,7 +2,7 @@ import path from 'path'
 import { Plugin } from '../plugin'
 import { ResolvedConfig } from '../config'
 import { CLIENT_ENTRY, ENV_ENTRY } from '../constants'
-import { normalizePath } from '../utils'
+import { isExternalUrl, normalizePath } from '../utils'
 
 // ids in transform are normalized to unix style
 const normalizedClientEntry = normalizePath(CLIENT_ENTRY)
@@ -36,7 +36,7 @@ export function clientInjectionsPlugin(config: ResolvedConfig): Plugin {
         if (options.path) {
           hmrBase = hmrBase + options.path
         }
-        if (hmrBase !== '/') {
+        if (hmrBase !== '/' && !isExternalUrl(hmrBase)) {
           port = path.posix.normalize(`${port}${hmrBase}`)
         }