feat(nuxt): introduce `imports.scan` option (#26576)

packages/nuxt/src/imports/module.ts

@@ -17,6 +17,7 @@ export default defineNuxtModule<Partial<ImportsOptions>>({
   },
   defaults: {
     autoImport: true,
+    scan: true,
     presets: defaultPresets,
     global: false,
     imports: [],
@@ -51,7 +52,12 @@ export default defineNuxtModule<Partial<ImportsOptions>>({
 
     // composables/ dirs from all layers
     let composablesDirs: string[] = []
+    if (options.scan) {
       for (const layer of nuxt.options._layers) {
+        // Layer disabled scanning for itself
+        if (layer.config?.imports?.scan === false) {
+          continue
+        }
         composablesDirs.push(resolve(layer.config.srcDir, 'composables'))
         composablesDirs.push(resolve(layer.config.srcDir, 'utils'))
         for (const dir of (layer.config.imports?.dirs ?? [])) {
@@ -75,6 +81,7 @@ export default defineNuxtModule<Partial<ImportsOptions>>({
           return nuxt.callHook('restart')
         }
       })
+    }
 
     // Support for importing from '#imports'
     addTemplate({
@@ -101,14 +108,18 @@ export default defineNuxtModule<Partial<ImportsOptions>>({
       await ctx.modifyDynamicImports(async (imports) => {
         // Clear old imports
         imports.length = 0
-        // Scan `composables/`
-        const composableImports = await scanDirExports(composablesDirs, {
+
+        // Scan for `composables/` and `utils/` directories
+        if (options.scan) {
+          const scannedImports = await scanDirExports(composablesDirs, {
             fileFilter: file => !isIgnored(file),
           })
-        for (const i of composableImports) {
+          for (const i of scannedImports) {
             i.priority = i.priority || priorities.find(([dir]) => i.from.startsWith(dir))?.[1]
           }
-        imports.push(...composableImports)
+          imports.push(...scannedImports)
+        }
+
         // Modules extending
         await nuxt.callHook('imports:extend', imports)
         return imports
@@ -127,7 +138,7 @@ export default defineNuxtModule<Partial<ImportsOptions>>({
     // Watch composables/ directory
     nuxt.hook('builder:watch', async (_, relativePath) => {
       const path = resolve(nuxt.options.srcDir, relativePath)
-      if (composablesDirs.some(dir => dir === path || path.startsWith(dir + '/'))) {
+      if (options.scan && composablesDirs.some(dir => dir === path || path.startsWith(dir + '/'))) {
         await regenerateImports()
       }
     })

packages/schema/src/types/imports.ts

@@ -15,6 +15,13 @@ export interface ImportsOptions extends UnimportOptions {
    */
   dirs?: string[]
 
+  /**
+   * Enabled scan for local directories for auto imports.
+   * When this is disabled, `dirs` options will be ignored.
+   * @default true
+   */
+  scan?: boolean
+
   /**
    * Assign auto imported utilities to `globalThis` instead of using built time transformation.
    * @default false