fix: avoid transforming twice, close #28

Author: antfu

src/core/transform.ts

@@ -9,6 +9,9 @@ import { resolveOptions } from './options'
 const scriptSetupRE = /<script\s(.*\s)?setup(\s.*)?>/
 
 export function shouldTransform(code: string, id: string, options?: ScriptSetupTransformOptions): boolean {
+  // avoid transforming twice
+  if (code.includes('export default __sfc_main'))
+    return false
   return (options?.refTransform && shouldTransformRefSugar(code)) || scriptSetupRE.test(code)
 }
 

test/transform.test.ts

@@ -19,7 +19,11 @@ describe('transform', () => {
         const warn = jest.spyOn(console, 'warn').mockImplementation(() => {})
 
         const fixture = await fs.readFile(resolve(root, file), 'utf-8')
-        expect(transform(fixture, file, { refTransform: true })?.code || fixture).toMatchSnapshot()
+        const result = transform(fixture, file, { refTransform: true })?.code || fixture
+        expect(result).toMatchSnapshot()
+
+        const result2 = transform(result, file, { refTransform: true })?.code || result
+        expect(result).toEqual(result2)
 
         warn.mockRestore()
       })