From baa9632a2c2befafdfde0f131f84f247fa8b6478 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=BF=A0=20/=20green?= <green@sapphi.red>
Date: Sat, 21 May 2022 05:32:52 +0900
Subject: [PATCH] fix(plugin-legacy): respect `entryFileNames` for polyfill
 chunks (#8247)

---
 packages/plugin-legacy/src/index.ts              | 14 +++++++++-----
 packages/vite/src/node/plugins/manifest.ts       |  3 ++-
 playground/legacy/__tests__/legacy.spec.ts       |  6 ++++++
 playground/legacy/vite.config-custom-filename.js |  2 +-
 playground/legacy/vite.config.js                 |  3 ++-
 5 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/packages/plugin-legacy/src/index.ts b/packages/plugin-legacy/src/index.ts
index dd0cf13dc81d16..f07fc9ee719119 100644
--- a/packages/plugin-legacy/src/index.ts
+++ b/packages/plugin-legacy/src/index.ts
@@ -131,11 +131,12 @@ function viteLegacyPlugin(options: Options = {}): Plugin[] {
             modernPolyfills
           )
         await buildPolyfillChunk(
-          'polyfills-modern',
           modernPolyfills,
           bundle,
           facadeToModernPolyfillMap,
           config.build,
+          'es',
+          opts,
           options.externalSystemJS
         )
         return
@@ -160,13 +161,14 @@ function viteLegacyPlugin(options: Options = {}): Plugin[] {
           )
 
         await buildPolyfillChunk(
-          'polyfills-legacy',
           legacyPolyfills,
           bundle,
           facadeToLegacyPolyfillMap,
           // force using terser for legacy polyfill minification, since esbuild
           // isn't legacy-safe
           config.build,
+          'iife',
+          opts,
           options.externalSystemJS
         )
       }
@@ -549,11 +551,12 @@ export async function detectPolyfills(
 }
 
 async function buildPolyfillChunk(
-  name: string,
   imports: Set<string>,
   bundle: OutputBundle,
   facadeToChunkMap: Map<string, string>,
   buildOptions: BuildOptions,
+  format: 'iife' | 'es',
+  rollupOutputOptions: NormalizedOutputOptions,
   externalSystemJS?: boolean
 ) {
   let { minify, assetsDir } = buildOptions
@@ -571,10 +574,11 @@ async function buildPolyfillChunk(
       assetsDir,
       rollupOptions: {
         input: {
-          [name]: polyfillId
+          polyfills: polyfillId
         },
         output: {
-          format: name.includes('legacy') ? 'iife' : 'es',
+          format,
+          entryFileNames: rollupOutputOptions.entryFileNames,
           manualChunks: undefined
         }
       }
diff --git a/packages/vite/src/node/plugins/manifest.ts b/packages/vite/src/node/plugins/manifest.ts
index 02fbdce63eec78..9784597195dc7c 100644
--- a/packages/vite/src/node/plugins/manifest.ts
+++ b/packages/vite/src/node/plugins/manifest.ts
@@ -37,7 +37,8 @@ export function manifestPlugin(config: ResolvedConfig): Plugin {
           )
           if (format === 'system' && !chunk.name.includes('-legacy')) {
             const ext = path.extname(name)
-            name = name.slice(0, -ext.length) + `-legacy` + ext
+            const endPos = ext.length !== 0 ? -ext.length : undefined
+            name = name.slice(0, endPos) + `-legacy` + ext
           }
           return name.replace(/\0/g, '')
         } else {
diff --git a/playground/legacy/__tests__/legacy.spec.ts b/playground/legacy/__tests__/legacy.spec.ts
index 489b410817c457..cbf44112b122c1 100644
--- a/playground/legacy/__tests__/legacy.spec.ts
+++ b/playground/legacy/__tests__/legacy.spec.ts
@@ -71,6 +71,12 @@ test('should load dynamic import with css', async () => {
 describe.runIf(isBuild)('build', () => {
   test('should generate correct manifest', async () => {
     const manifest = readManifest()
+    // legacy polyfill
+    expect(manifest['../../vite/legacy-polyfills-legacy']).toBeDefined()
+    expect(manifest['../../vite/legacy-polyfills-legacy'].src).toBe(
+      '../../vite/legacy-polyfills-legacy'
+    )
+    // modern polyfill
     expect(manifest['../../vite/legacy-polyfills']).toBeDefined()
     expect(manifest['../../vite/legacy-polyfills'].src).toBe(
       '../../vite/legacy-polyfills'
diff --git a/playground/legacy/vite.config-custom-filename.js b/playground/legacy/vite.config-custom-filename.js
index 9a96133b015588..d1aea865ef5581 100644
--- a/playground/legacy/vite.config-custom-filename.js
+++ b/playground/legacy/vite.config-custom-filename.js
@@ -1,7 +1,7 @@
 const legacy = require('@vitejs/plugin-legacy').default
 
 module.exports = {
-  plugins: [legacy()],
+  plugins: [legacy({ modernPolyfills: true })],
   build: {
     manifest: true,
     minify: false,
diff --git a/playground/legacy/vite.config.js b/playground/legacy/vite.config.js
index e1d68245604346..c21813971716b5 100644
--- a/playground/legacy/vite.config.js
+++ b/playground/legacy/vite.config.js
@@ -6,7 +6,8 @@ module.exports = {
   base: './',
   plugins: [
     legacy({
-      targets: 'IE 11'
+      targets: 'IE 11',
+      modernPolyfills: true
     })
   ],