fix: only force split async chunks when format is esm or cjs (#1152)

Author: Timeless0911

packages/core/src/config.ts

@@ -513,10 +513,6 @@ export async function createConstantRsbuildConfig(): Promise<EnvironmentConfig>
       htmlPlugin: false,
       rspack: {
         optimization: {
-          splitChunks: {
-            // Splitted "sync" chunks will make entry modules can't be inlined.
-            chunks: 'async',
-          },
           moduleIds: 'named',
           nodeEnv: false,
         },
@@ -604,6 +600,10 @@ const composeFormatConfig = ({
               concatenateModules: true,
               sideEffects: 'flag',
               avoidEntryIife: true,
+              splitChunks: {
+                // Splitted "sync" chunks will make entry modules can't be inlined.
+                chunks: 'async',
+              },
             },
             output: {
               module: true,
@@ -634,6 +634,12 @@ const composeFormatConfig = ({
                 },
               },
             },
+            optimization: {
+              splitChunks: {
+                // Splitted "sync" chunks will make entry modules can't be inlined.
+                chunks: 'async',
+              },
+            },
             output: {
               iife: false,
               chunkFormat: 'commonjs',

packages/core/tests/__snapshots__/config.test.ts.snap

@@ -157,9 +157,6 @@ exports[`Should compose create Rsbuild config correctly > Merge Rsbuild config i
             "optimization": {
               "moduleIds": "named",
               "nodeEnv": false,
-              "splitChunks": {
-                "chunks": "async",
-              },
             },
             "resolve": {
               "extensionAlias": {
@@ -208,6 +205,9 @@ exports[`Should compose create Rsbuild config correctly > Merge Rsbuild config i
               "avoidEntryIife": true,
               "concatenateModules": true,
               "sideEffects": "flag",
+              "splitChunks": {
+                "chunks": "async",
+              },
             },
             "output": {
               "chunkFormat": "module",
@@ -434,9 +434,6 @@ exports[`Should compose create Rsbuild config correctly > Merge Rsbuild config i
             "optimization": {
               "moduleIds": "named",
               "nodeEnv": false,
-              "splitChunks": {
-                "chunks": "async",
-              },
             },
             "resolve": {
               "extensionAlias": {
@@ -474,6 +471,11 @@ exports[`Should compose create Rsbuild config correctly > Merge Rsbuild config i
                 },
               },
             },
+            "optimization": {
+              "splitChunks": {
+                "chunks": "async",
+              },
+            },
             "output": {
               "chunkFormat": "commonjs",
               "chunkLoading": "require",
@@ -668,9 +670,6 @@ exports[`Should compose create Rsbuild config correctly > Merge Rsbuild config i
             "optimization": {
               "moduleIds": "named",
               "nodeEnv": false,
-              "splitChunks": {
-                "chunks": "async",
-              },
             },
             "resolve": {
               "extensionAlias": {
@@ -898,9 +897,6 @@ exports[`Should compose create Rsbuild config correctly > Merge Rsbuild config i
             "optimization": {
               "moduleIds": "named",
               "nodeEnv": false,
-              "splitChunks": {
-                "chunks": "async",
-              },
             },
             "resolve": {
               "extensionAlias": {
@@ -1085,9 +1081,6 @@ exports[`Should compose create Rsbuild config correctly > Merge Rsbuild config i
             "optimization": {
               "moduleIds": "named",
               "nodeEnv": false,
-              "splitChunks": {
-                "chunks": "async",
-              },
             },
             "resolve": {
               "extensionAlias": {