fix(compiler-sfc): fix 'export default' rewrite with extra whitespaces (#4375)

packages/compiler-sfc/__tests__/compileScript.spec.ts

@@ -140,6 +140,43 @@ defineExpose({ foo: 123 })
   })
 
   describe('<script> and <script setup> co-usage', () => {
+    describe('spaces in ExportDefaultDeclaration node', () => {
+      // #4371
+      test('with many spaces and newline', () => {
+        // #4371
+        const { content } = compile(`
+        <script>
+        export const n = 1
+        export        default     
+        {   
+          some:'option'
+        }
+        </script>
+        <script setup>
+        import { x } from './x'
+        x()
+        </script>
+        `)
+        assertCode(content)
+      })
+
+      test('with minimal spaces', () => {
+        const { content } = compile(`
+        <script>
+        export const n = 1
+        export default{   
+          some:'option'
+        }
+        </script>
+        <script setup>
+        import { x } from './x'
+        x()
+        </script>
+        `)
+        assertCode(content)
+      })
+    })
+
     test('script first', () => {
       const { content } = compile(`
       <script>