fix: preserve original extension when extension redirection is disabled

packages/core/src/config.ts

@@ -1448,14 +1448,15 @@ const composeBundlelessExternalConfig = (
               return;
             }
             const { issuer } = contextInfo;
+            const originExtension = extname(request);
 
             if (!resolver) {
               resolver = getResolve() as RspackResolver;
             }
 
             async function redirectPath(
               request: string,
-            ): Promise<string | undefined> {
+            ): Promise<{ path?: string; isResolved: boolean }> {
               try {
                 let resolvedRequest = request;
                 // use resolver to resolve the request
@@ -1485,19 +1486,29 @@ const composeBundlelessExternalConfig = (
                   ) {
                     resolvedRequest = `./${resolvedRequest}`;
                   }
-                  return resolvedRequest;
+                  return {
+                    path: resolvedRequest,
+                    isResolved: true,
+                  };
                 }
                 // NOTE: If request is a phantom dependency, which means it can be resolved but not specified in dependencies or peerDependencies in package.json, the output will be incorrect to use when the package is published
                 // return the original request instead of the resolved request
-                return undefined;
+                return {
+                  path: undefined,
+                  isResolved: true,
+                };
               } catch (_e) {
                 // catch error when request can not be resolved by resolver
                 // e.g. A react component library importing and using 'react' but while not defining
                 // it in devDependencies and peerDependencies. Preserve 'react' as-is if so.
                 logger.debug(
                   `Failed to resolve module ${color.green(`"${request}"`)} from ${color.green(issuer)}. If it's an npm package, consider adding it to dependencies or peerDependencies in package.json to make it externalized.`,
                 );
-                return request;
+                // return origin request instead of undefined for cssExternalHandler
+                return {
+                  path: request,
+                  isResolved: false,
+                };
               }
             }
 
@@ -1506,7 +1517,8 @@ const composeBundlelessExternalConfig = (
             if (issuer) {
               let resolvedRequest: string = request;
 
-              const redirectedPath = await redirectPath(resolvedRequest);
+              const { path: redirectedPath, isResolved } =
+                await redirectPath(resolvedRequest);
               const cssExternal = await cssExternalHandler(
                 resolvedRequest,
                 callback,
@@ -1537,18 +1549,20 @@ const composeBundlelessExternalConfig = (
               // If data.request already have an extension, we replace it with new extension
               // This may result in a change in semantics,
               // user should use copy to keep origin file or use another separate entry to deal this
-              if (resolvedRequest.startsWith('.')) {
+              if (resolvedRequest.startsWith('.') && isResolved) {
                 const ext = extname(resolvedRequest);
 
                 if (ext) {
                   // 1. js files hit JS_EXTENSIONS_PATTERN, ./foo.ts -> ./foo.mjs
                   if (JS_EXTENSIONS_PATTERN.test(resolvedRequest)) {
-                    if (jsRedirectExtension) {
-                      resolvedRequest = resolvedRequest.replace(
-                        /\.[^.]+$/,
-                        jsExtension,
-                      );
-                    }
+                    resolvedRequest = resolvedRequest.replace(
+                      /\.[^.]+$/,
+                      jsRedirectExtension
+                        ? jsExtension
+                        : JS_EXTENSIONS_PATTERN.test(originExtension)
+                          ? originExtension
+                          : '',
+                    );
                   } else {
                     // 2. asset files, does not match jsExtensionsPattern, eg: ./foo.png -> ./foo.mjs
                     // non-js && non-css files
@@ -1569,7 +1583,7 @@ const composeBundlelessExternalConfig = (
                     // If the import path refers to a directory,
                     // it most likely actually refers to a `index.*` file due to Node's module resolution.
                     // When redirect.js.path is set to false, index should still be added before adding extension.
-                    // When redirect.js.path is true, the resolver directly generate correct resolvedRequest with index appended.
+                    // When redirect.js.path is set to true, the resolver directly generates correct resolvedRequest with index appended.
                     if (
                       !jsRedirectPath &&
                       (await isDirectory(

packages/plugin-dts/README.md

@@ -233,7 +233,7 @@ const defaultRedirect = {
 };
 ```
 
-Controls the redirect of the import paths of output TypeScript declaration files.
+Controls the redirect of the import paths of TypeScript declaration output files.
 
 ```js
 pluginDts({
@@ -269,9 +269,9 @@ import { foo } from '../foo'; // expected output './dist/utils/index.d.ts'
 - **Type:** `boolean`
 - **Default:** `false`
 
-Whether to automatically redirect the file extension to import paths based on the TypeScript declaration output files.
+Whether to automatically redirect the file extension of import paths based on the TypeScript declaration output files.
 
-- When set to `true`, the import paths in declaration files will be redirected to the corresponding JavaScript extension which can be resolved to corresponding declaration file. The extension of the declaration output file is related to the `dtsExtension` configuration.
+- When set to `true`, the file extension of the import path in the declaration file will be automatically completed or replaced with the corresponding JavaScript file extension that can be resolved to the corresponding declaration file. The extension of the declaration output file is related to the `dtsExtension` configuration.
 
 ```ts
 // `dtsExtension` is set to `.d.mts`
@@ -282,7 +282,7 @@ import { foo } from './foo.ts'; // source code of './src/bar.ts' ↓
 import { foo } from './foo.mjs'; // expected output of './dist/bar.d.mts'
 ```
 
-- When set to `false`, the file extension will remain unchanged from the original import path in the rewritten import path of the output file (regardless of whether it is specified or specified as any value).
+- When set to `false`, import paths will retain their original file extensions.
 
 ### tsgo
 

tests/integration/preserve-jsx/__snapshots__/index.test.ts.snap

@@ -29,12 +29,12 @@ __webpack_require__.r(__webpack_exports__);
 __webpack_require__.d(__webpack_exports__, {
     default: ()=>Root
 });
-const external_App1_cjs_namespaceObject = require("./App1.cjs");
-const external_App2_cjs_namespaceObject = require("./App2.cjs");
+const external_App1_namespaceObject = require("./App1");
+const external_App2_namespaceObject = require("./App2");
 const DynamicComponent = ()=>{
-    const Component = Math.random() > 0.5 ? external_App1_cjs_namespaceObject.App1A : external_App1_cjs_namespaceObject.App1C;
-    return import("./App1.cjs").then((mod)=>{
-        const Dynamic = mod[Component === external_App1_cjs_namespaceObject.App1A ? 'App1A' : 'App1C'];
+    const Component = Math.random() > 0.5 ? external_App1_namespaceObject.App1A : external_App1_namespaceObject.App1C;
+    return import("./App1").then((mod)=>{
+        const Dynamic = mod[Component === external_App1_namespaceObject.App1A ? 'App1A' : 'App1C'];
         return <Dynamic/>;
     });
 };
@@ -47,51 +47,51 @@ function Root() {
     return <>
       <React.Fragment>
         <>
-          <external_App1_cjs_namespaceObject.App1A/>
+          <external_App1_namespaceObject.App1A/>
           <React.Suspense fallback={<div>Loading...</div>}>
             <DynamicComponent/>
           </React.Suspense>
         </>
       </React.Fragment>
-      <external_App1_cjs_namespaceObject.App1C>
-        {x ? <external_App1_cjs_namespaceObject.App1A>
-            <external_App1_cjs_namespaceObject.App1B>
-              <external_App2_cjs_namespaceObject.App2 props={external_App2_cjs_namespaceObject.app2Props}>
-                <external_App1_cjs_namespaceObject.App1C props={external_App1_cjs_namespaceObject.app1cProps}/>
-              </external_App2_cjs_namespaceObject.App2>
-            </external_App1_cjs_namespaceObject.App1B>
-          </external_App1_cjs_namespaceObject.App1A> : <external_App1_cjs_namespaceObject.App1B/>}
-      </external_App1_cjs_namespaceObject.App1C>
-      <external_App1_cjs_namespaceObject.App1C className="c"/>
-      <external_App1_cjs_namespaceObject.App1C className="app1c"></external_App1_cjs_namespaceObject.App1C>
-      <external_App1_cjs_namespaceObject.App1B/>
+      <external_App1_namespaceObject.App1C>
+        {x ? <external_App1_namespaceObject.App1A>
+            <external_App1_namespaceObject.App1B>
+              <external_App2_namespaceObject.App2 props={external_App2_namespaceObject.app2Props}>
+                <external_App1_namespaceObject.App1C props={external_App1_namespaceObject.app1cProps}/>
+              </external_App2_namespaceObject.App2>
+            </external_App1_namespaceObject.App1B>
+          </external_App1_namespaceObject.App1A> : <external_App1_namespaceObject.App1B/>}
+      </external_App1_namespaceObject.App1C>
+      <external_App1_namespaceObject.App1C className="c"/>
+      <external_App1_namespaceObject.App1C className="app1c"></external_App1_namespaceObject.App1C>
+      <external_App1_namespaceObject.App1B/>
       <NamespaceComponents.Button label="Namespace button" {...{
         title: 'extra',
         ['data-role']: 'primary'
-    }} data-count={3} icon={<external_App1_cjs_namespaceObject.App1A/>} fragmentContent={<>
+    }} data-count={3} icon={<external_App1_namespaceObject.App1A/>} fragmentContent={<>
             <span>Nested</span>
             <span>Fragment</span>
           </>}/>
       <div className="wrapper">
         {[
         <section key="namespace-import" data-index="0">
-            <external_App1_cjs_namespaceObject.App data-dynamic="registry" data-item="one"/>
+            <external_App1_namespaceObject.App data-dynamic="registry" data-item="one"/>
             <foo:bar value="namespaced"/>
             <svg:path d="M0,0 L10,10" xlink:href="#one"/>
             <span>{'item-one'.toUpperCase()}</span>
             {}
           </section>,
         <section key="legacy-widget" data-index="1">
-            <external_App2_cjs_namespaceObject.App2 data-dynamic="registry" data-item="two" {...external_App2_cjs_namespaceObject.app2Props}/>
+            <external_App2_namespaceObject.App2 data-dynamic="registry" data-item="two" {...external_App2_namespaceObject.app2Props}/>
             app2
-            <external_App2_cjs_namespaceObject.App2/>
+            <external_App2_namespaceObject.App2/>
             <foo:bar value="namespaced-two"/>
             <svg:path d="M10,10 L20,20" xlink:href="#two"/>
-            <external_App1_cjs_namespaceObject.App1A/>
+            <external_App1_namespaceObject.App1A/>
             {}
           </section>,
         <section key="external-app" data-index="2">
-            <external_App1_cjs_namespaceObject.App1A data-dynamic="registry" data-item="fallback"/>
+            <external_App1_namespaceObject.App1A data-dynamic="registry" data-item="fallback"/>
             <foo:bar value="namespaced-three"/>
             <svg:path d="M20,20 L30,30" xlink:href="#three"/>
             {(()=><NamespaceComponents.Button label="Inline child"/>)()}
@@ -120,11 +120,11 @@ Object.defineProperty(exports, '__esModule', {
 `;
 
 exports[`JSX syntax should be preserved 2`] = `
-"import { App, App1A, App1B, App1C, app1cProps } from "./App1.js";
-import { App2, app2Props } from "./App2.js";
+"import { App, App1A, App1B, App1C, app1cProps } from "./App1";
+import { App2, app2Props } from "./App2";
 const DynamicComponent = ()=>{
     const Component = Math.random() > 0.5 ? App1A : App1C;
-    return import("./App1.js").then((mod)=>{
+    return import("./App1").then((mod)=>{
         const Dynamic = mod[Component === App1A ? 'App1A' : 'App1C'];
         return <Dynamic/>;
     });
@@ -205,11 +205,11 @@ export { Root as default };
 `;
 
 exports[`JSX syntax should be preserved 3`] = `
-"import { App, App1A, App1B, App1C, app1cProps } from "./App1.jsx";
-import { App2, app2Props } from "./App2.jsx";
+"import { App, App1A, App1B, App1C, app1cProps } from "./App1";
+import { App2, app2Props } from "./App2";
 const DynamicComponent = ()=>{
     const Component = Math.random() > 0.5 ? App1A : App1C;
-    return import("./App1.jsx").then((mod)=>{
+    return import("./App1").then((mod)=>{
         const Dynamic = mod[Component === App1A ? 'App1A' : 'App1C'];
         return <Dynamic/>;
     });

tests/integration/redirect/js-not-resolve/src/index.js

@@ -3,6 +3,11 @@ import lodash from 'lodash';
 // can be resolved but not specified -- phantom dependency
 import prettier from 'prettier';
 import bar from './bar.js';
+import baz from './baz.cjs';
 import foo from './foo';
+import foo_node from './foo.node';
+import foo_node_js from './foo.node.js';
 
-export default lodash.toUpper(foo + bar + typeof prettier.version);
+export default lodash.toUpper(
+  foo + foo_node + foo_node_js + bar + baz + typeof prettier.version,
+);

tests/integration/redirect/js.test.ts

@@ -28,6 +28,11 @@ test('redirect.js default', async () => {
     import { baz } from "./baz.js";
     export * from "./.hidden.js";
     export * from "./.hidden-folder/index.js";
+    export * from "./bar.node.js";
+    export * from "./bar.node.js";
+    export * from "./bar.node.js";
+    export * from "./foo.js";
+    export * from "./foo.js";
     const src = lodash.toUpper(lodash_merge(foo) + bar + foo + bar + baz + typeof prettier.version);
     export { src as default };
     "
@@ -57,6 +62,11 @@ test('redirect.js.path false', async () => {
     import { foo as external_foo_js_foo } from "./foo.js";
     export * from "./.hidden.js";
     export * from "./.hidden-folder/index.js";
+    export * from "./bar.node.js";
+    export * from "./bar.node.js";
+    export * from "./bar.node.js";
+    export * from "./foo.js";
+    export * from "./foo.js";
     const src = lodash.toUpper(lodash_merge(external_foo_js_foo) + index_js_bar + foo + bar + baz + typeof prettier.version);
     export { src as default };
     "
@@ -84,6 +94,11 @@ test('redirect.js.path with user override externals', async () => {
     import { foo as external_foo_js_foo } from "./foo.js";
     export * from "./.hidden.js";
     export * from "./.hidden-folder/index.js";
+    export * from "./bar.node.js";
+    export * from "./bar.node.js";
+    export * from "./bar.node.js";
+    export * from "./foo.js";
+    export * from "./foo.js";
     const src = lodash.toUpper(lodash_merge(external_foo_js_foo) + index_js_bar + foo + bar + baz + typeof prettier.version);
     export { src as default };
     "
@@ -119,6 +134,11 @@ test('redirect.js.path with user override alias', async () => {
     import { foo as external_foo_js_foo } from "./foo.js";
     export * from "./.hidden.js";
     export * from "./.hidden-folder/index.js";
+    export * from "./bar.node.js";
+    export * from "./bar.node.js";
+    export * from "./bar.node.js";
+    export * from "./foo.js";
+    export * from "./foo.js";
     const src = lodash.toUpper(lodash_merge(external_foo_js_foo) + index_js_bar + foo + bar + baz + typeof prettier.version);
     export { src as default };
     "
@@ -138,15 +158,21 @@ test('redirect.js.extension: false', async () => {
     contents.esm4!,
     /esm\/index\.js/,
   );
+
   expect(indexContent).toMatchInlineSnapshot(`
     "import lodash from "lodash";
     import lodash_merge from "lodash.merge";
     import prettier from "prettier";
-    import { bar } from "./bar/index.ts";
-    import { foo } from "./foo.ts";
-    import { baz } from "./baz.ts";
-    export * from "./.hidden.ts";
-    export * from "./.hidden-folder/index.ts";
+    import { bar } from "./bar/index";
+    import { foo } from "./foo";
+    import { baz } from "./baz";
+    export * from "./.hidden";
+    export * from "./.hidden-folder/index";
+    export * from "./bar.node";
+    export * from "./bar.node.js";
+    export * from "./bar.node.ts";
+    export * from "./foo.js";
+    export * from "./foo.ts";
     const src = lodash.toUpper(lodash_merge(foo) + bar + foo + bar + baz + typeof prettier.version);
     export { src as default };
     "

tests/integration/redirect/js/src/bar.node.ts

@@ -0,0 +1 @@
+export const bar_node = 'bar node';

tests/integration/redirect/js/src/index.ts

@@ -1,6 +1,5 @@
-// can not be resolved
-import lodash from 'lodash';
 // can be resolved, 3rd party packages
+import lodash from 'lodash';
 import merge from 'lodash.merge';
 // can be resolved but not specified -- phantom dependency
 import prettier from 'prettier';
@@ -14,6 +13,11 @@ import { foo } from './foo';
 
 export * from './.hidden';
 export * from './.hidden-folder';
+export * from './bar.node';
+export * from './bar.node.js';
+export * from './bar.node.ts';
+export * from './foo.js';
+export * from './foo.ts';
 
 export default lodash.toUpper(
   merge(foo) + bar + foo2 + bar2 + baz + typeof prettier.version,

tests/integration/redirect/js/tsconfig.json

@@ -2,6 +2,8 @@
   "extends": "@rslib/tsconfig/base",
   "compilerOptions": {
     "baseUrl": "./",
+    "noEmit": true,
+    "allowImportingTsExtensions": true,
     "paths": {
       "@/*": ["./src/*"]
     }