fix: serve index.html from public subdirectories

packages/vite/src/node/preview.ts

@@ -244,7 +244,7 @@ export async function preview(
     sirv(distDir, {
       etag: true,
       dev: true,
-      extensions: [],
+      extensions: ['.html'],
       ignores: false,
       setHeaders(res) {
         if (headers) {

packages/vite/src/node/server/__tests__/watcher.spec.ts

@@ -53,4 +53,17 @@ describe('watcher configuration', () => {
       )
     })
   })
+
+  it('should not watch a non-existent public directory', async () => {
+    const root = fileURLToPath(
+      new URL('./fixtures/watcher/nested-root', import.meta.url),
+    )
+    const nonExistentPublicDir = resolve(root, '../non-existent-public')
+    server = await createServer({ root, publicDir: nonExistentPublicDir })
+    await new Promise((resolve) => server!.watcher.once('ready', resolve))
+    await vi.waitFor(() => {
+      const watchedDirs = Object.keys(server!.watcher.getWatched())
+      expect(watchedDirs).not.toContain(nonExistentPublicDir)
+    })
+  })
 })

packages/vite/src/node/server/index.ts

@@ -548,7 +548,7 @@ export async function _createServer(
           ...getEnvFilesForMode(config.mode, config.envDir),
           // Watch the public directory explicitly because it might be outside
           // of the root directory.
-          ...(publicDir && publicFiles ? [publicDir] : []),
+          ...(publicDir && publicFiles?.size ? [publicDir] : []),
         ],
 
         resolvedWatchOptions,

packages/vite/src/node/server/middlewares/static.ts

@@ -41,7 +41,6 @@ const sirvOptions = ({
   return {
     dev: true,
     etag: true,
-    extensions: [],
     setHeaders(res, pathname) {
       // Matches js, jsx, ts, tsx, mts, mjs, cjs, cts, ctx, mtx
       // The reason this is done, is that the .ts and .mts file extensions are
@@ -82,14 +81,14 @@ export function servePublicMiddleware(
   publicFiles?: Set<string>,
 ): Connect.NextHandleFunction {
   const dir = server.config.publicDir
-  const serve = sirv(
-    dir,
-    sirvOptions({
+  const serve = sirv(dir, {
+    ...sirvOptions({
       config: server.config,
       getHeaders: () => server.config.server.headers,
       disableFsServeCheck: true,
     }),
-  )
+    extensions: ['.html'],
+  })
 
   const toFilePath = (url: string) => {
     let filePath = cleanUrl(url)