feat: add skipNodeModulesBundle option

src/features/external.ts

@@ -1,15 +1,26 @@
+import path from 'node:path'
 import type { PackageJson } from 'pkg-types'
 import type { InputOptions, Plugin } from 'rolldown'
 
 export type External = InputOptions['external']
 
-export function ExternalPlugin(pkg: PackageJson): Plugin {
+export function ExternalPlugin(
+  pkg: PackageJson,
+  skipNodeModulesBundle?: boolean,
+): Plugin {
   const deps = Array.from(getProductionDeps(pkg))
   return {
     name: 'tsdown:external',
-    resolveId(id) {
+    resolveId(id, importer, { isEntry }) {
+      if (isEntry) return
+
+      const EXTERNAL = { id, external: true }
+
+      if (skipNodeModulesBundle && !path.isAbsolute(id) && id[0] !== '.') {
+        return EXTERNAL
+      }
       if (deps.some((dep) => id === dep || id.startsWith(`${dep}/`))) {
-        return { id, external: true }
+        return EXTERNAL
       }
     },
   }

src/index.ts

@@ -63,9 +63,9 @@ export async function buildSingle(resolved: ResolvedOptions): Promise<void> {
     treeshake,
     platform,
     plugins: [
-      pkg && ExternalPlugin(pkg),
-      dts && IsolatedDecl.rolldown(dts === true ? {} : dts),
+      pkg && ExternalPlugin(pkg, resolved.skipNodeModulesBundle),
       unused && Unused.rolldown(unused === true ? {} : unused),
+      dts && IsolatedDecl.rolldown(dts === true ? {} : dts),
       ...plugins,
     ].filter((plugin) => !!plugin),
     ...resolved.inputOptions,

src/options.ts

@@ -58,6 +58,11 @@ export interface Options {
         format: ModuleFormat,
       ) => MaybePromise<OutputOptions | void | null>)
   onSuccess?: () => void | Promise<void>
+
+  /**
+   * Skip bundling node_modules.
+   */
+  skipNodeModulesBundle?: boolean
 }
 
 /**
@@ -108,6 +113,7 @@ export async function resolveOptions(
         dts = false,
         unused = false,
         watch = false,
+        skipNodeModulesBundle = false,
       } = subOptions
 
       entry = await resolveEntry(entry)
@@ -128,6 +134,7 @@ export async function resolveOptions(
         dts,
         unused,
         watch,
+        skipNodeModulesBundle,
       }
     }),
   )

tsdown.config.ts

@@ -5,6 +5,7 @@ export default defineConfig({
   format: 'esm',
   clean: true,
   platform: 'node',
+  skipNodeModulesBundle: true,
   dts: true,
   unused: { level: 'error' },
   onSuccess() {