From 232265783670563e34cf96240bf0e383a3653e6c Mon Sep 17 00:00:00 2001
From: Minjee Son <104430030+iammminzzy@users.noreply.github.com>
Date: Tue, 30 Apr 2024 04:11:42 +0100
Subject: [PATCH] feat(plugin-legacy): support `additionalModernPolyfills`
 (#16514)

---
 packages/plugin-legacy/README.md    | 6 +++++-
 packages/plugin-legacy/src/index.ts | 5 +++++
 packages/plugin-legacy/src/types.ts | 1 +
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/packages/plugin-legacy/README.md b/packages/plugin-legacy/README.md
index 1b759d7fb17ce2..a1475b54c5f79b 100644
--- a/packages/plugin-legacy/README.md
+++ b/packages/plugin-legacy/README.md
@@ -74,7 +74,11 @@ npm add -D terser
 
   Add custom imports to the legacy polyfills chunk. Since the usage-based polyfill detection only covers ES language features, it may be necessary to manually specify additional DOM API polyfills using this option.
 
-  Note: if additional polyfills are needed for both the modern and legacy chunks, they can simply be imported in the application source code.
+### `additionalModernPolyfills`
+
+- **Type:** `string[]`
+
+  Add custom imports to the modern polyfills chunk. Since the usage-based polyfill detection only covers ES language features, it may be necessary to manually specify additional DOM API polyfills using this option.
 
 ### `modernPolyfills`
 
diff --git a/packages/plugin-legacy/src/index.ts b/packages/plugin-legacy/src/index.ts
index ad821f857ab593..d1489fda5bb91d 100644
--- a/packages/plugin-legacy/src/index.ts
+++ b/packages/plugin-legacy/src/index.ts
@@ -166,6 +166,11 @@ function viteLegacyPlugin(options: Options = {}): Plugin[] {
       )
     })
   }
+  if (Array.isArray(options.additionalModernPolyfills)) {
+    options.additionalModernPolyfills.forEach((i) => {
+      modernPolyfills.add(i)
+    })
+  }
   if (Array.isArray(options.polyfills)) {
     options.polyfills.forEach((i) => {
       if (i.startsWith(`regenerator`)) {
diff --git a/packages/plugin-legacy/src/types.ts b/packages/plugin-legacy/src/types.ts
index 282c447adc6f69..bd2d239c0aab8d 100644
--- a/packages/plugin-legacy/src/types.ts
+++ b/packages/plugin-legacy/src/types.ts
@@ -12,6 +12,7 @@ export interface Options {
    */
   polyfills?: boolean | string[]
   additionalLegacyPolyfills?: string[]
+  additionalModernPolyfills?: string[]
   /**
    * default: false
    */