fix: support .vue files as direct entry inputs

closes #188

Author: sxzz

src/tsc/emit-compiler.ts

@@ -77,6 +77,23 @@ function createTsProgram({
       : undefined,
   )
 
+  // TypeScript's createProgram silently skips root files with unsupported
+  // extensions (.vue is not .ts/.tsx/.d.ts). The only way .vue files enter a
+  // program is through module resolution (imports from a .ts file). When .vue
+  // files are direct entries without a .ts file importing them, we add a
+  // bridge .ts file to context.files so volar can discover them. (#188)
+  let vueBridgePath: string | undefined
+  if (vue && entries) {
+    const vueEntries = entries.filter((e) => e.endsWith('.vue'))
+    if (vueEntries.length > 0) {
+      vueBridgePath = path.join(baseDir, '__rolldown_dts_vue_bridge__.ts')
+      context.files.set(
+        vueBridgePath,
+        vueEntries.map((e) => `import '${e.replaceAll('\\', '/')}'`).join('\n'),
+      )
+    }
+  }
+
   debug(`creating program for root project: ${baseDir}`)
   return createTsProgramFromParsedConfig({
     parsedConfig,
@@ -86,6 +103,7 @@ function createTsProgram({
     entries,
     vue,
     tsMacro,
+    vueBridgePath,
   })
 }
 
@@ -97,10 +115,12 @@ function createTsProgramFromParsedConfig({
   entries,
   vue,
   tsMacro,
+  vueBridgePath,
 }: {
   parsedConfig: ts.ParsedCommandLine
   fsSystem: ts.System
   baseDir: string
+  vueBridgePath?: string
 } & Pick<TscOptions, 'entries' | 'vue' | 'tsMacro' | 'id'>): TscModule {
   const compilerOptions: ts.CompilerOptions = {
     ...defaultCompilerOptions,
@@ -116,8 +136,13 @@ function createTsProgramFromParsedConfig({
       ),
     ),
   ]
+  if (vueBridgePath) {
+    rootNames.push(vueBridgePath)
+  }
 
   const host = ts.createCompilerHost(compilerOptions, true)
+  host.readFile = (fileName) => fsSystem.readFile(fileName)
+  host.fileExists = (fileName) => fsSystem.fileExists(fileName)
 
   const createProgram = createProgramFactory(ts, { vue, tsMacro })
   const program = createProgram({

tests/__snapshots__/tsc.test.ts.snap

@@ -477,6 +477,34 @@ interface Unused {
 export { Unused };"
 `;
 
+exports[`tsc > vue-sfc as entry input #188 1`] = `
+"// Bar.vue.d.ts
+import * as _vue_runtime_core0 from "@vue/runtime-core";
+
+//#region tests/fixtures/vue-sfc-entry/Bar.vue.d.ts
+declare const __VLS_export: _vue_runtime_core0.DefineComponent<{}, {}, {}, {}, {}, _vue_runtime_core0.ComponentOptionsMixin, _vue_runtime_core0.ComponentOptionsMixin, {}, string, _vue_runtime_core0.PublicProps, Readonly<{}> & Readonly<{}>, {}, {}, {}, {}, string, _vue_runtime_core0.ComponentProvideOptions, true, {}, any>;
+declare const _default: typeof __VLS_export;
+//#endregion
+export { _default as default };
+// Foo.vue.d.ts
+import { Bar } from "./baz.js";
+import * as _vue_runtime_core0 from "@vue/runtime-core";
+
+//#region tests/fixtures/vue-sfc-entry/Foo.vue.d.ts
+type __VLS_Props = {
+  foo: Bar;
+};
+declare const __VLS_export: _vue_runtime_core0.DefineComponent<__VLS_Props, {}, {}, {}, {}, _vue_runtime_core0.ComponentOptionsMixin, _vue_runtime_core0.ComponentOptionsMixin, {}, string, _vue_runtime_core0.PublicProps, Readonly<__VLS_Props> & Readonly<{}>, {}, {}, {}, {}, string, _vue_runtime_core0.ComponentProvideOptions, false, {}, any>;
+declare const _default: typeof __VLS_export;
+//#endregion
+export { _default as default };
+// baz.d.ts
+//#region tests/fixtures/vue-sfc-entry/bar/baz.d.ts
+type Bar = 'bar' | 'baz';
+//#endregion
+export { Bar };"
+`;
+
 exports[`tsc > vue-sfc w/ ts-compiler 1`] = `
 "// main.d.ts
 import * as _vue_runtime_core0 from "@vue/runtime-core";

tests/fixtures/vue-sfc-entry/Bar.vue

@@ -0,0 +1,3 @@
+<template>
+  <div>Bar</div>
+</template>

tests/fixtures/vue-sfc-entry/Foo.vue

@@ -0,0 +1,11 @@
+<script setup lang="ts">
+import type { Bar } from './bar/baz'
+
+defineProps<{
+  foo: Bar
+}>()
+</script>
+
+<template>
+  {{ foo }}
+</template>

tests/fixtures/vue-sfc-entry/bar/baz.ts

@@ -0,0 +1 @@
+export type Bar = 'bar' | 'baz'

tests/tsc.test.ts

@@ -213,6 +213,28 @@ describe('tsc', () => {
     expect(snapshot).toMatchSnapshot()
   })
 
+  test('vue-sfc as entry input #188', async () => {
+    const root = path.resolve(dirname, 'fixtures/vue-sfc-entry')
+    const { snapshot } = await rolldownBuild(
+      [
+        path.resolve(root, 'Foo.vue'),
+        path.resolve(root, 'Bar.vue'),
+        path.resolve(root, 'bar/baz.ts'),
+      ],
+      [
+        dts({
+          emitDtsOnly: true,
+          vue: true,
+          compilerOptions: {
+            isolatedDeclarations: false,
+          },
+        }),
+      ],
+      { external: ['vue'] },
+    )
+    expect(snapshot).toMatchSnapshot()
+  })
+
   test('vue-sfc w/ ts-compiler w/ vueCompilerOptions in tsconfig', async () => {
     const root = path.resolve(dirname, 'fixtures/vue-sfc-fallthrough')
     const { snapshot } = await rolldownBuild(