fix: set filename dynamically using a function

packages/core/src/config.ts

@@ -855,25 +855,29 @@ const composeAutoExtensionConfig = (
   };
 
   const hash = getHash();
-
-  const updatedConfig: EnvironmentConfig = {
-    output: {
-      filename: {
-        js: `[name]${hash}${jsExtension}`,
-        ...config.output?.filename,
-      },
-    },
-  };
-
-  const updatedJsExtension =
-    typeof updatedConfig.output?.filename?.js === 'string' &&
-    updatedConfig.output?.filename?.js
-      ? extname(updatedConfig.output.filename.js)
+  const defaultJsFilename = `[name]${hash}${jsExtension}`;
+  const userJsFilename = config.output?.filename?.js;
+
+  // will be returned to use in redirect feature
+  // only support string type for now since we can not get the return value of function
+  const finalJsExtension =
+    typeof userJsFilename === 'string' && userJsFilename
+      ? extname(userJsFilename)
       : jsExtension;
 
+  const finalConfig = userJsFilename
+    ? {}
+    : {
+        output: {
+          filename: {
+            js: defaultJsFilename,
+          },
+        },
+      };
+
   return {
-    config: updatedConfig,
-    jsExtension: updatedJsExtension,
+    config: finalConfig,
+    jsExtension: finalJsExtension,
     dtsExtension,
   };
 };

tests/integration/auto-extension/index.test.ts

@@ -1,5 +1,9 @@
 import { extname, join } from 'node:path';
-import { buildAndGetResults, queryContent } from 'test-helper';
+import {
+  buildAndGetResults,
+  generateFileTree,
+  queryContent,
+} from 'test-helper';
 import { describe, expect, test } from 'vitest';
 
 describe('autoExtension: true', () => {
@@ -52,6 +56,22 @@ describe('should respect output.filename.js and output.filenameHash to override
     expect(entryFiles.cjs1).toMatchInlineSnapshot(
       `"<ROOT>/tests/integration/auto-extension/type-commonjs/config-override/dist/cjs-override-filename-hash/index.df02628a.js"`,
     );
+
+    // override different file types with function
+    const fileTree = generateFileTree(
+      join(fixturePath, './dist/cjs-override-filename-function'),
+    );
+    expect(fileTree).toMatchInlineSnapshot(`
+      {
+        "bar-image.js": "<ROOT>/tests/integration/auto-extension/type-commonjs/config-override/dist/cjs-override-filename-function/bar-image.js",
+        "bar-index.js": "<ROOT>/tests/integration/auto-extension/type-commonjs/config-override/dist/cjs-override-filename-function/bar-index.js",
+        "static": {
+          "image": {
+            "foo-image.png": "<ROOT>/tests/integration/auto-extension/type-commonjs/config-override/dist/cjs-override-filename-function/static/image/foo-image.png",
+          },
+        },
+      }
+    `);
   });
 
   test('type is module', async () => {
@@ -71,6 +91,22 @@ describe('should respect output.filename.js and output.filenameHash to override
     expect(entryFiles.cjs1).toMatchInlineSnapshot(
       `"<ROOT>/tests/integration/auto-extension/type-module/config-override/dist/cjs-override-filename-hash/index.df02628a.js"`,
     );
+
+    // override different file types with function
+    const fileTree = generateFileTree(
+      join(fixturePath, './dist/esm-override-filename-function'),
+    );
+    expect(fileTree).toMatchInlineSnapshot(`
+      {
+        "bar-image.js": "<ROOT>/tests/integration/auto-extension/type-module/config-override/dist/esm-override-filename-function/bar-image.js",
+        "bar-index.js": "<ROOT>/tests/integration/auto-extension/type-module/config-override/dist/esm-override-filename-function/bar-index.js",
+        "static": {
+          "image": {
+            "foo-image.png": "<ROOT>/tests/integration/auto-extension/type-module/config-override/dist/esm-override-filename-function/static/image/foo-image.png",
+          },
+        },
+      }
+    `);
   });
 });
 

tests/integration/auto-extension/type-commonjs/config-override/rslib.config.ts

@@ -41,6 +41,30 @@ export default defineConfig({
         },
       },
     }),
+    generateBundleCjsConfig({
+      output: {
+        filename: {
+          image: () => {
+            return 'foo-[name][ext]';
+          },
+          js: () => {
+            return 'bar-[name].js';
+          },
+        },
+        distPath: {
+          root: './dist/cjs-override-filename-function',
+        },
+      },
+      bundle: false,
+      source: {
+        entry: {
+          index: [
+            '../../__fixtures__/src/index.ts',
+            '../../__fixtures__/src/image.png',
+          ],
+        },
+      },
+    }),
   ],
   source: {
     entry: {

tests/integration/auto-extension/type-module/config-override/rslib.config.ts

@@ -41,6 +41,30 @@ export default defineConfig({
         },
       },
     }),
+    generateBundleEsmConfig({
+      output: {
+        filename: {
+          image: () => {
+            return 'foo-[name][ext]';
+          },
+          js: () => {
+            return 'bar-[name].js';
+          },
+        },
+        distPath: {
+          root: './dist/esm-override-filename-function',
+        },
+      },
+      bundle: false,
+      source: {
+        entry: {
+          index: [
+            '../../__fixtures__/src/index.ts',
+            '../../__fixtures__/src/image.png',
+          ],
+        },
+      },
+    }),
   ],
   source: {
     entry: {

website/docs/en/guide/migration/modernjs-module.mdx

@@ -189,4 +189,4 @@ export default defineConfig({
 
 This migration doc is contributed by community user [YanPes](https://github.com/YanPes). Much appreciation for his contribution!
 
-Rslib is designed to be next generation of Modern.js Module and we will provide more detailed guide and scripts for migration in 2025 Q1.
+Rslib is designed to be the next generation solution of Modern.js Module, and we will provide detailed configuration mapping documentation as well as feature migration guides and scripts in the second quarter of 2025.

website/docs/zh/guide/migration/modernjs-module.mdx

@@ -189,4 +189,4 @@ export default defineConfig({
 
 此迁移文档由社区用户 [YanPes](https://github.com/YanPes) 贡献。非常感谢他的贡献！
 
-Rslib 旨在成为 Modern.js Module 的下一代解决方案，我们将在 2025 年第一季度提供更多详细的迁移指南和脚本。
+Rslib 旨在成为 Modern.js Module 的下一代解决方案，我们将在 2025 年第二季度提供详细的配置映射文档以及功能迁移指南与脚本。