fix: make <script> src required

Author: hydrati

packages/compiler-sfc/src/parse.ts

@@ -47,6 +47,7 @@ export interface SFCScriptBlock extends SFCBlock {
   imports?: Record<string, ImportBinding>
   scriptAst?: import('@babel/types').Statement[]
   scriptSetupAst?: import('@babel/types').Statement[]
+  src: string
 }
 
 export interface SFCStyleBlock extends SFCBlock {
@@ -97,7 +98,7 @@ export function parse(
     pad = false,
     ignoreEmpty = true,
     compiler = CompilerDOM,
-    defaultScriptLang
+    defaultScriptLang = 'js'
   }: SFCParseOptions = {}
 ): SFCParseResult {
   const sourceKey =
@@ -107,7 +108,7 @@ export function parse(
     sourceRoot +
     pad +
     compiler.parse +
-    (defaultScriptLang != null ? '@' + defaultScriptLang : '')
+    defaultScriptLang
   const cache = sourceToSFC.get(sourceKey)
   if (cache) {
     return cache