fix: always emit declarations for vue files

Author: danielroe

src/mkdist.ts

@@ -109,7 +109,7 @@ function defineVueLoader(options?: DefineVueLoaderOptions): Loader {
     )
 
     if (!modified) {
-      return
+      return output
     }
 
     const contents = results

test/mkdist.test.ts

@@ -241,6 +241,13 @@ describe('transform typescript script setup', () => {
       export default _default;
       "
     `)
+
+    expect(await fixture(`<template><div /></template>`)).toMatchInlineSnapshot(`"<template><div /></template>"`)
+    expect(await declaration(`<template><div /></template>`)).toMatchInlineSnapshot(`
+      "declare const _default: import("vue").DefineComponent<{}, {}, {}, {}, {}, import("vue").ComponentOptionsMixin, import("vue").ComponentOptionsMixin, {}, string, import("vue").PublicProps, Readonly<{}> & Readonly<{}>, {}, {}, {}, {}, string, import("vue").ComponentProvideOptions, true, {}, any>;
+      export default _default;
+      "
+    `)
   })
 
   async function fixture(src: string): Promise<string> {
@@ -256,11 +263,11 @@ describe('transform typescript script setup', () => {
     return await readFile(join(tmpDir, 'dist/index.vue'), 'utf-8')
   }
 
-  async function declaration(src: string): Promise<string> {
+  async function declaration(src: string): Promise<string | undefined> {
     await rm(tmpDir, { force: true, recursive: true })
     await mkdir(join(tmpDir, 'src'), { recursive: true })
     await writeFile(join(tmpDir, 'src/index.vue'), src)
     await mkdist({ declaration: true, loaders: ['js', vueLoader], rootDir: tmpDir })
-    return await readFile(join(tmpDir, 'dist/index.vue.d.ts'), 'utf-8')
+    return await readFile(join(tmpDir, 'dist/index.vue.d.ts'), 'utf-8').catch(() => undefined)
   }
 })