feat(nuxt3): support lazy and custom-resolved components (#3814)

docs/content/3.docs/2.directory-structure/4.components.md

@@ -47,6 +47,39 @@ If you have a component in nested directories such as:
 For clarity, we recommend that the component's file name matches its name. (So, in the example above, you could rename `Button.vue` to be `BaseFooButton.vue`.)
 ::
 
+## Dynamic components
+
+If you want to use the Vue `<component :is="someComputedComponent">` syntax, then you will need to use the `resolveComponent` helper provided by Vue.
+
+For example:
+
+```vue
+<template>
+  <component :is="clickable ? MyButton : 'div'" />
+</template>
+
+<script setup>
+const MyButton = resolveComponent('MyButton')
+</script>
+```
+
+Alternatively, though not recommended, you can register all your components globally, which will create async chunks for all your components and make them available throughout your application.
+
+```diff
+  import { defineNuxtConfig } from 'nuxt3'
+  
+  export default defineNuxtConfig({
+    components: {
++     global: true,
++     dirs: ['~/components']
+    },
+  })
+```
+
+::alert{type=info}
+The `global` option can also be set per component directory.
+::
+
 ## Dynamic Imports
 
 To dynamically import a component (also known as lazy-loading a component) all you need to do is add the `Lazy` prefix to the component's name.

packages/nuxt3/src/auto-imports/presets.ts

@@ -104,6 +104,7 @@ export const vuePreset = defineUnimportPreset({
     // Component
     'defineComponent',
     'defineAsyncComponent',
+    'resolveComponent',
     'getCurrentInstance',
     'h',
     'inject',

packages/nuxt3/src/components/loader.ts

@@ -2,7 +2,7 @@ import { pathToFileURL } from 'url'
 import { createUnplugin } from 'unplugin'
 import { parseQuery, parseURL } from 'ufo'
 import { Component } from '@nuxt/schema'
-import { genImport } from 'knitwork'
+import { genDynamicImport, genImport } from 'knitwork'
 import MagicString from 'magic-string'
 import { pascalCase } from 'scule'
 
@@ -37,13 +37,19 @@ function transform (code: string, id: string, components: Component[]) {
   const s = new MagicString(code)
 
   // replace `_resolveComponent("...")` to direct import
-  s.replace(/ _resolveComponent\("(.*?)"\)/g, (full, name) => {
+  s.replace(/(?<=[ (])_?resolveComponent\(["'](lazy-|Lazy)?([^'"]*?)["']\)/g, (full, lazy, name) => {
     const component = findComponent(components, name)
     if (component) {
       const identifier = map.get(component) || `__nuxt_component_${num++}`
       map.set(component, identifier)
-      imports.add(genImport(component.filePath, [{ name: component.export, as: identifier }]))
+      if (lazy) {
-      return ` ${identifier}`
+        // Nuxt will auto-import `defineAsyncComponent` for us
+        imports.add(`const ${identifier}_lazy = defineAsyncComponent(${genDynamicImport(component.filePath)})`)
+        return `${identifier}_lazy`
+      } else {
+        imports.add(genImport(component.filePath, [{ name: component.export, as: identifier }]))
+        return identifier
+      }
     }
     // no matched
     return full

packages/nuxt3/src/components/templates.ts

@@ -51,6 +51,7 @@ export const componentsTypeTemplate = {
 declare module 'vue' {
   export interface GlobalComponents {
 ${options.components.map(c => `    '${c.pascalName}': typeof ${genDynamicImport(isAbsolute(c.filePath) ? relative(join(options.buildDir, 'types'), c.filePath) : c.filePath, { wrapper: false })}['${c.export}']`).join(',\n')}
+${options.components.map(c => `    'Lazy${c.pascalName}': typeof ${genDynamicImport(isAbsolute(c.filePath) ? relative(join(options.buildDir, 'types'), c.filePath) : c.filePath, { wrapper: false })}['${c.export}']`).join(',\n')}
   }
 }
 export {}

packages/schema/src/config/_adhoc.ts

@@ -9,6 +9,8 @@ export default {
    * @see [Nuxt 3](https://v3.nuxtjs.org/docs/directory-structure/components) and
    * [Nuxt 2](https://nuxtjs.org/docs/directory-structure/components/) documentation
    * @type {boolean | typeof import('../src/types/components').ComponentsOptions | typeof import('../src/types/components').ComponentsOptions['dirs']}
+   * @version 2
+   * @version 3
    */
   components: {
     $resolve: (val, get) => {
@@ -27,6 +29,7 @@ export default {
    *
    * @see [Nuxt 3 documentation](https://v3.nuxtjs.org/docs/directory-structure/composables)
    * @type {typeof import('../src/types/imports').AutoImportsOptions}
+   * @version 3
    */
   autoImports: {
     global: false,