refactor(nuxt)!: move head option support into defineNuxtComponent (#8901)

docs/content/3.api/3.utils/define-nuxt-component.md

@@ -5,10 +5,10 @@ description: defineNuxtComponent() is a helper function for defining type safe c
 
 # `defineNuxtComponent`
 
-`defineNuxtComponent()` is a helper function for defining type safe Vue components using options API similar to [defineComponent()](https://vuejs.org/api/general.html#definecomponent). `defineNuxtComponent()` wrapper also adds support for `asyncData` component option.
+`defineNuxtComponent()` is a helper function for defining type safe Vue components using options API similar to [defineComponent()](https://vuejs.org/api/general.html#definecomponent). `defineNuxtComponent()` wrapper also adds support for `asyncData` and `head` component options.
 
 ::alert{type=warning}
-Options API support for `asyncData` may well change before the stable release of Nuxt 3.
+Options API support for `asyncData` and `head` may well change before the stable release of Nuxt 3.
 ::
 
 ::Alert
@@ -34,3 +34,19 @@ export default defineNuxtComponent({
 })
 </script>
 ```
+
+## `head()`
+
+If you choose not to use `setup()` in your app, you can use the `head()` method within your component definition:
+
+```vue [pages/index.vue]
+<script lang="ts">
+export default defineNuxtComponent({
+  head(nuxtApp) {
+    return {
+      title: 'My site'
+    }
+  },
+})
+</script>
+```

packages/nuxt/src/app/composables/component.ts

@@ -4,6 +4,9 @@ import { NuxtApp, useNuxtApp } from '../nuxt'
 import { useAsyncData } from './asyncData'
 import { useRoute } from './router'
 
+// eslint-disable-next-line import/no-restricted-paths
+import { useHead } from '#head'
+
 export const NuxtComponentIndicator = '__nuxt_component'
 
 async function runLegacyAsyncData (res: Record<string, any> | Promise<Record<string, any>>, fn: (nuxtApp: NuxtApp) => Promise<Record<string, any>>) {
@@ -25,7 +28,7 @@ export const defineNuxtComponent: typeof defineComponent =
     const { setup } = options
 
     // Avoid wrapping if no options api is used
-    if (!setup && !options.asyncData) {
+    if (!setup && !options.asyncData && !options.head) {
       return {
         [NuxtComponentIndicator]: true,
         ...options
@@ -43,6 +46,11 @@ export const defineNuxtComponent: typeof defineComponent =
           promises.push(runLegacyAsyncData(res, options.asyncData))
         }
 
+        if (options.head) {
+          const nuxtApp = useNuxtApp()
+          useHead(typeof options.head === 'function' ? () => options.head(nuxtApp) : options.head)
+        }
+
         return Promise.resolve(res)
           .then(() => Promise.all(promises))
           .then(() => res)

packages/nuxt/src/app/index.ts

@@ -10,7 +10,7 @@ export type { PageMeta } from '../pages/runtime'
 // eslint-disable-next-line import/no-restricted-paths
 export type { MetaObject } from '../head/runtime'
 // eslint-disable-next-line import/no-restricted-paths
-export { useHead, useMeta } from '#head'
+export { useHead } from '#head'
 
 export const isVue2 = false
 export const isVue3 = true

packages/nuxt/src/head/module.ts

@@ -29,9 +29,6 @@ export default defineNuxtModule({
       })
     }
 
-    // Add mixin plugin
-    addPlugin({ src: resolve(runtimeDir, 'mixin-plugin') })
-
     // Add library specific plugin
     addPlugin({ src: resolve(runtimeDir, 'lib/vueuse-head.plugin') })
   }

packages/nuxt/src/head/runtime/composables.ts

@@ -12,9 +12,3 @@ import { useNuxtApp } from '#app'
 export function useHead (meta: MaybeComputedRef<MetaObject>) {
   useNuxtApp()._useHead(meta)
 }
-
-// TODO: remove useMeta support when Nuxt 3 is stable
-/** @deprecated Please use new `useHead` composable instead */
-export function useMeta (meta: MaybeComputedRef<MetaObject>) {
-  return useHead(meta)
-}

packages/nuxt/src/head/runtime/mixin-plugin.ts

@@ -1,24 +0,0 @@
-import { getCurrentInstance } from 'vue'
-import { useHead } from './composables'
-import { defineNuxtPlugin, useNuxtApp } from '#app'
-
-const metaMixin = {
-  created () {
-    const instance = getCurrentInstance()
-    if (!instance) { return }
-
-    const options = instance.type
-    if (!options || !('head' in options)) { return }
-
-    const nuxtApp = useNuxtApp()
-    const source = typeof options.head === 'function'
-      ? () => options.head(nuxtApp)
-      : options.head
-
-    useHead(source)
-  }
-}
-
-export default defineNuxtPlugin((nuxtApp) => {
-  nuxtApp.vueApp.mixin(metaMixin)
-})

packages/nuxt/src/imports/presets.ts

@@ -5,8 +5,7 @@ const commonPresets: InlinePreset[] = [
   defineUnimportPreset({
     from: '#head',
     imports: [
-      'useHead',
-      'useMeta'
+      'useHead'
     ]
   }),
   // vue-demi (mocked)

test/basic.test.ts

@@ -253,7 +253,6 @@ describe('head tags', () => {
     expect(headHtml).toContain('<meta name="description" content="overriding with an inline useHead call">')
     expect(headHtml).toMatch(/<html[^>]*class="html-attrs-test"/)
     expect(headHtml).toMatch(/<body[^>]*class="body-attrs-test"/)
-    expect(headHtml).toContain('script>console.log("works with useMeta too")</script>')
     expect(headHtml).toContain('<script src="https://a-body-appended-script.com" data-meta-body></script></body>')
 
     const indexHtml = await $fetch('/')

test/bundle.test.ts

@@ -29,6 +29,7 @@ describe.skipIf(isWindows)('minimal nuxt application', () => {
     expect(stats.client.totalBytes).toBeLessThan(110000)
     expect(stats.client.files.map(f => f.replace(/\..*\.js/, '.js'))).toMatchInlineSnapshot(`
       [
+        "_nuxt/composables.js",
         "_nuxt/entry.js",
         "_nuxt/error-404.js",
         "_nuxt/error-500.js",

test/fixtures/basic/pages/head.vue

@@ -1,35 +1,32 @@
-<script setup>
-const a = ref('')
-
-useHead({
-  // title template function example
-  titleTemplate: title => `${title} - Title Template Fn Change`,
-  bodyAttrs: {
-    class: 'body-attrs-test'
-  },
-  script: [
-    {
-      src: 'https://a-body-appended-script.com',
-      body: true
-    }
-  ],
-  meta: [{ name: 'description', content: 'first' }]
-})
-useHead({ meta: [{ charset: 'utf-16' }, { name: 'description', content: computed(() => `${a.value} with an inline useHead call`) }] })
-useMeta({ script: [{ children: 'console.log("works with useMeta too")' }] })
-a.value = 'overriding'
-</script>
-
 <script>
-export default {
+export default defineNuxtComponent({
   head () {
     return {
       htmlAttrs: {
         class: 'html-attrs-test'
       }
     }
+  },
+  setup () {
+    const a = ref('')
+    useHead({
+      // title template function example
+      titleTemplate: title => `${title} - Title Template Fn Change`,
+      bodyAttrs: {
+        class: 'body-attrs-test'
+      },
+      script: [
+        {
+          src: 'https://a-body-appended-script.com',
+          body: true
+        }
+      ],
+      meta: [{ name: 'description', content: 'first' }]
+    })
+    useHead({ meta: [{ charset: 'utf-16' }, { name: 'description', content: computed(() => `${a.value} with an inline useHead call`) }] })
+    a.value = 'overriding'
   }
-}
+})
 </script>
 
 <template>