refactor: default to warning

src/core/options.ts

@@ -1,22 +1,26 @@
 import type { FilterPattern } from '@rollup/pluginutils'
 
 export interface Options {
-  enable?: boolean
   root?: string
   include?: FilterPattern
   exclude?: FilterPattern
+  /**
+   * @default 'warning'
+   */
+  level?: 'warning' | 'error'
 }
 
 type Overwrite<T, U> = Pick<T, Exclude<keyof T, keyof U>> & U
 
 export type OptionsResolved = Overwrite<
   Required<Options>,
-  Pick<Options, 'enable' | 'root'>
+  Pick<Options, 'root'>
 >
 
 export function resolveOptions(options: Options): OptionsResolved {
   return {
     include: options.include || [/\.([cm]?[jt]sx?|vue)$/],
     exclude: options.exclude || [/node_modules/],
+    level: options.level || 'warning',
   }
 }

src/index.ts

@@ -47,15 +47,19 @@ const plugin: UnpluginInstance<Options | undefined, false> = createUnplugin(
 
       buildEnd() {
         if (deps.size) {
-          throw new Error(
+          const error = new Error(
             `Unused dependencies found: ${Array.from(deps).join(', ')}`,
           )
+          if (options.level === 'error') {
+            throw error
+          } else {
+            console.warn(error)
+          }
         }
       },
 
       vite: {
         configResolved(config) {
-          options.enable ??= config.command === 'build'
           options.root ||= config.root
         },
       },

tsup.config.ts

@@ -9,5 +9,5 @@ export default defineConfig({
   cjsInterop: true,
   clean: true,
   dts: true,
-  esbuildPlugins: [Unused()],
+  esbuildPlugins: [Unused({ level: 'error' })],
 })