From 417208cf28cecc4cdfa04ca8f456d2b7c6b343d2 Mon Sep 17 00:00:00 2001
From: untp <54450843+untp@users.noreply.github.com>
Date: Sun, 19 Sep 2021 14:52:42 +0300
Subject: [PATCH] fix(ssr): add normalizePath to require.resolve, fix #2393
 (#4980)

---
 packages/vite/src/node/ssr/ssrExternal.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/packages/vite/src/node/ssr/ssrExternal.ts b/packages/vite/src/node/ssr/ssrExternal.ts
index 99dcd0d44aa3fb..2950846b8c8ff5 100644
--- a/packages/vite/src/node/ssr/ssrExternal.ts
+++ b/packages/vite/src/node/ssr/ssrExternal.ts
@@ -5,6 +5,7 @@ import {
   createDebugger,
   isDefined,
   lookupFile,
+  normalizePath,
   resolveFrom,
   unique
 } from '../utils'
@@ -68,7 +69,9 @@ export function resolveSSRExternal(
         undefined,
         true
       )?.id
-      requireEntry = require.resolve(id, { paths: [root] })
+      // normalizePath required for windows. tryNodeResolve uses normalizePath
+      // which returns with '/', require.resolve returns with '\\'
+      requireEntry = normalizePath(require.resolve(id, { paths: [root] }))
     } catch (e) {
       // resolve failed, assume include
       debug(`Failed to resolve entries for package "${id}"\n`, e)