From 91eadffb50965ed49505a6e56711030452977529 Mon Sep 17 00:00:00 2001
From: Jono Mingard <reason.koan@gmail.com>
Date: Fri, 14 Jul 2023 09:57:47 +0900
Subject: [PATCH] fix(build): inject css below use strict directive

---
 packages/vite/src/node/plugins/css.ts | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/packages/vite/src/node/plugins/css.ts b/packages/vite/src/node/plugins/css.ts
index cf21b1a974e42a..9c530f9cfbf9b2 100644
--- a/packages/vite/src/node/plugins/css.ts
+++ b/packages/vite/src/node/plugins/css.ts
@@ -682,10 +682,15 @@ export function cssPostPlugin(config: ResolvedConfig): Plugin {
             `var ${style} = document.createElement('style');` +
             `${style}.textContent = ${cssString};` +
             `document.head.appendChild(${style});`
+          let injectionPoint
           const wrapIdx = code.indexOf('System.register')
-          const executeFnStart =
-            wrapIdx >= 0 ? code.indexOf('execute:', wrapIdx) : 0
-          const injectionPoint = code.indexOf('{', executeFnStart) + 1
+          if (wrapIdx >= 0) {
+            const executeFnStart = code.indexOf('execute:', wrapIdx)
+            injectionPoint = code.indexOf('{', executeFnStart) + 1
+          } else {
+            const insertMark = "'use strict';"
+            injectionPoint = code.indexOf(insertMark) + insertMark.length
+          }
           const s = new MagicString(code)
           s.appendRight(injectionPoint, injectCode)
           if (config.build.sourcemap) {