fix: vite preview base path support

examples/react/start-basic-static/src/router.tsx

@@ -6,6 +6,7 @@ import { NotFound } from './components/NotFound'
 export function getRouter() {
   const router = createRouter({
     routeTree,
+    basepath: '/test/',
     defaultPreload: 'intent',
     defaultErrorComponent: DefaultCatchBoundary,
     defaultNotFoundComponent: () => <NotFound />,

examples/react/start-basic-static/vite.config.ts

@@ -5,6 +5,7 @@ import viteReact from '@vitejs/plugin-react'
 import tailwindcss from '@tailwindcss/vite'
 
 export default defineConfig({
+  base: '/test/',
   server: {
     port: 3000,
   },

packages/start-plugin-core/src/prerender.ts

@@ -1,7 +1,7 @@
 import { promises as fsp } from 'node:fs'
 import os from 'node:os'
 import path from 'pathe'
-import { joinURL, withBase, withoutBase } from 'ufo'
+import { joinURL, withBase, withTrailingSlash, withoutBase } from 'ufo'
 import { VITE_ENVIRONMENT_NAMES } from './constants'
 import { createLogger } from './utils'
 import { Queue } from './queue'
@@ -164,7 +164,7 @@ export async function prerender({
           // Fetch the route
 
           const res = await localFetch(
-            withBase(page.path, routerBasePath),
+            withTrailingSlash(withBase(page.path, routerBasePath)),
             {
               headers: {
                 ...(prerenderOptions.headers ?? {}),

packages/start-plugin-core/src/preview-server-plugin/plugin.ts

@@ -1,6 +1,7 @@
 import { pathToFileURL } from 'node:url'
 import { basename, extname, join } from 'pathe'
 import { NodeRequest, sendNodeResponse } from 'srvx/node'
+import { joinURL } from 'ufo'
 import { VITE_ENVIRONMENT_NAMES } from '../constants'
 import { getServerOutputDirectory } from '../output-directory'
 import type { Plugin } from 'vite'
@@ -43,6 +44,9 @@ export function previewServerPlugin(): Plugin {
                 serverBuild = imported.default
               }
 
+              // Prepend base path to request URL to match routing setup
+              req.url = joinURL(server.config.base, req.url ?? '/')
+
               const webReq = new NodeRequest({ req, res })
               const webRes: Response = await serverBuild.fetch(webReq)