feat: enabld dts only when typescript is installed

package.json

@@ -71,6 +71,7 @@
   "dependencies": {
     "@antfu/utils": "^0.3.0",
     "@rollup/pluginutils": "^4.1.1",
+    "has-pkg": "^0.0.1",
     "magic-string": "^0.25.7",
     "unplugin": "^0.2.1"
   },

src/core/options.ts

@@ -1,17 +1,22 @@
 import { resolve } from 'path'
 import { toArray } from '@antfu/utils'
 import { createFilter } from '@rollup/pluginutils'
+import hasPkg from 'has-pkg'
 import { presets } from '../presets'
 import { ImportInfo, ImportsFlatMap, Options, ResolvedOptions } from '../types'
 
 export function resolveOptions(options: Options = {}): ResolvedOptions {
   const imports = flattenImportsMap(options.imports, options.presetOverriding)
+
+  const { dts = hasPkg('typescript') } = options
   const resolved: ResolvedOptions = {
     sourceMap: false,
     ...options,
-    dts: options.dts === false
+    dts: dts === false
       ? false
-      : resolve(options.dts || 'auto-imports.d.ts'),
+      : dts === true
+        ? resolve('auto-imports.d.ts')
+        : resolve(dts),
     imports,
     matchRE: new RegExp(`\\b(${Object.keys(imports).join('|')})\\b`, 'g'),
     idFilter: createFilter(

src/types.ts

@@ -27,11 +27,12 @@ export interface Options {
   imports?: Arrayable<ImportsMap | PresetName>
   /**
    * Filepath to generate corresponding .d.ts file.
+   * Default enabled when `typescript` is installed locally.
    * Set `false` to disable.
    *
    * @default './auto-imports.d.ts'
    */
-  dts?: string | false
+  dts?: string | boolean
   /**
    * Allow overriding imports sources from multiple presets.
    *
@@ -52,7 +53,7 @@ export interface Options {
   exclude?: FilterPattern
   /**
    * Generate source map.
-   * 
+   *
    * @default false
    */
   sourceMap?: boolean
@@ -64,7 +65,7 @@ export interface TransformOptions {
 
   /**
    * Generate source map.
-   * 
+   *
    * @default false
    */
   sourceMap?: boolean