fix(vite): add additional before skipping vite transform

packages/vite/src/client.ts

@@ -130,11 +130,17 @@ export async function buildClient (ctx: ViteBuildContext) {
         next()
       }
     })
+
     const viteMiddleware = defineEventHandler(async (event) => {
       // Workaround: vite devmiddleware modifies req.url
       const originalURL = event.node.req.url!
-      // @ts-expect-error _skip_transform is a private property
-      event.node.req._skip_transform = !originalURL.startsWith(clientConfig.base!)
+
+      const viteRoutes = viteServer.middlewares.stack.map(m => m.route).filter(r => r.length > 1)
+      if (!originalURL.startsWith(clientConfig.base!) && !viteRoutes.some(route => originalURL.startsWith(route))) {
+        // @ts-expect-error _skip_transform is a private property
+        event.node.req._skip_transform = true
+      }
+
       await new Promise((resolve, reject) => {
         viteServer.middlewares.handle(event.node.req, event.node.res, (err: Error) => {
           event.node.req.url = originalURL

test/basic.test.ts

@@ -894,6 +894,16 @@ describe('component islands', () => {
   })
 })
 
+describe.runIf(process.env.NUXT_TEST_DEV && !process.env.TEST_WITH_WEBPACK)('vite plugins', () => {
+  it('does not override vite plugins', async () => {
+    expect(await $fetch('/vite-plugin-without-path')).toBe('vite-plugin without path')
+    expect(await $fetch('/__nuxt-test')).toBe('vite-plugin with __nuxt prefix')
+  })
+  it('does not allow direct access to nuxt source folder', async () => {
+    expect(await $fetch('/app.config')).toContain('404')
+  })
+})
+
 describe.skipIf(process.env.NUXT_TEST_DEV || isWindows)('payload rendering', () => {
   it('renders a payload', async () => {
     const payload = await $fetch('/random/a/_payload.js', { responseType: 'text' })

test/fixtures/basic/nuxt.config.ts

@@ -100,6 +100,28 @@ export default defineNuxtConfig({
         export: 'namedExport',
         filePath: '~/other-components-folder/named-export'
       })
+    },
+    'vite:extendConfig' (config) {
+      config.plugins!.push({
+        name: 'nuxt:server',
+        configureServer (server) {
+          server.middlewares.use((req, res, next) => {
+            if (req.url === '/vite-plugin-without-path') {
+              res.end('vite-plugin without path')
+              return
+            }
+            next()
+          })
+
+          server.middlewares.use((req, res, next) => {
+            if (req.url === '/__nuxt-test') {
+              res.end('vite-plugin with __nuxt prefix')
+              return
+            }
+            next()
+          })
+        }
+      })
     }
   },
   experimental: {