fix(nuxt): show client error if no page matches after validate fails (#18978)

packages/nuxt/src/pages/runtime/validate.ts

@@ -1,11 +1,38 @@
-import { defineNuxtRouteMiddleware } from '#app/composables/router'
+import { createError, showError } from '#app/composables/error'
+import { callWithNuxt, useNuxtApp } from '#app/nuxt'
+import { defineNuxtRouteMiddleware, useRouter } from '#app/composables/router'
 
 export default defineNuxtRouteMiddleware(async (to) => {
   if (!to.meta?.validate) { return }
 
+  const nuxtApp = useNuxtApp()
+  const router = useRouter()
+
   const result = await Promise.resolve(to.meta.validate(to))
   if (result === true) {
     return
   }
-  return result
+  if (process.server) {
+    return result
+  }
+  const error = createError({
+    statusCode: 404,
+    statusMessage: `Page Not Found: ${to.fullPath}`
+  })
+  const unsub = router.beforeResolve((final) => {
+    unsub()
+    if (final === to) {
+      const unsub = router.afterEach(async () => {
+        unsub()
+        await callWithNuxt(nuxtApp, showError, [error])
+        // We pretend to have navigated to the invalid route so
+        // that the user can return to the previous page with
+        // the back button.
+        window.history.pushState({}, '', to.fullPath)
+      })
+      // We stop the navigation immediately before it resolves
+      // if there is no other route matching it.
+      return false
+    }
+  })
 })

test/basic.test.ts

@@ -98,6 +98,16 @@ describe('pages', () => {
   it('validates routes', async () => {
     const { status } = await fetch('/forbidden')
     expect(status).toEqual(404)
+
+    const page = await createPage('/navigate-to-forbidden')
+    await page.waitForLoadState('networkidle')
+    await page.getByText('should throw a 404 error').click()
+    expect(await page.getByRole('heading').textContent()).toMatchInlineSnapshot('"Page Not Found: /forbidden"')
+
+    page.goto(url('/navigate-to-forbidden'))
+    await page.waitForLoadState('networkidle')
+    await page.getByText('should be caught by catchall').click()
+    expect(await page.getByRole('heading').textContent()).toMatchInlineSnapshot('"[...slug].vue"')
   })
 
   it('render 404', async () => {
@@ -107,7 +117,7 @@ describe('pages', () => {
     // expect(html).toMatchInlineSnapshot()
 
     expect(html).toContain('[...slug].vue')
-    expect(html).toContain('404 at not-found')
+    expect(html).toContain('catchall at not-found')
 
     // Middleware still runs after validation: https://github.com/nuxt/nuxt/issues/15650
     expect(html).toContain('Middleware ran: true')
@@ -941,7 +951,7 @@ describe.runIf(isDev() && !isWebpack)('vite plugins', () => {
     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')
+    expect(await $fetch('/app.config')).toContain('catchall at')
   })
 })
 

test/fixtures/basic/error.vue

@@ -0,0 +1,15 @@
+<template>
+  <div>
+    <div>
+      <h1>{{ error?.message }}</h1>
+      This is the error page 😱
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+import type { NuxtError } from '#app'
+defineProps({
+  error: Object as () => NuxtError
+})
+</script>

test/fixtures/basic/pages/[...slug].vue

@@ -1,7 +1,7 @@
 <template>
   <div>
-    <div>[...slug].vue</div>
+    <h1>[...slug].vue</h1>
-    <div>404 at {{ $route.params.slug[0] }}</div>
+    <div>catchall at {{ $route.params.slug[0] }}</div>
     <div>Middleware ran: {{ !!($route.meta.override as any)?.includes('extended middleware') }}</div>
   </div>
 </template>

test/fixtures/basic/pages/navigate-to-forbidden.vue

@@ -0,0 +1,18 @@
+<template>
+  <div>
+    <div>navigate-to-forbidden.vue</div>
+    <NuxtLink to="/forbidden">
+      should throw a 404 error
+    </NuxtLink>
+    <NuxtLink to="/some-404">
+      should be caught by catchall
+    </NuxtLink>
+  </div>
+</template>
+
+<script setup lang="ts">
+definePageMeta({
+  middleware: ['override'],
+  validate: to => to.path !== '/forbidden'
+})
+</script>

test/hmr.test.ts

@@ -70,7 +70,7 @@ if (process.env.TEST_ENV !== 'built' && !isWindows) {
 
     it('should detect new routes', async () => {
       const html = await $fetch('/some-404')
-      expect(html).toContain('404 at some-404')
+      expect(html).toContain('catchall at some-404')
 
       // write new page route
       const indexVue = await fsp.readFile(join(fixturePath, 'pages/index.vue'), 'utf8')