fix: avoid import external module re-assigin in concatenation (#7839)

* fix: avoid import external module re-assigin in concatenation

* test: add test

crates/rspack_core/src/concatenated_module.rs

@@ -755,6 +755,21 @@ impl Module for ConcatenatedModule {
             }
           }
 
+          // Handle the name passed through by namespace_export_symbol
+          if let Some(ref namespace_export_symbol) = info.namespace_export_symbol {
+            if namespace_export_symbol.starts_with(NAMESPACE_OBJECT_EXPORT)
+              && namespace_export_symbol.len() > NAMESPACE_OBJECT_EXPORT.len()
+            {
+              let name =
+                Atom::from(namespace_export_symbol[NAMESPACE_OBJECT_EXPORT.len()..].to_string());
+              all_used_names.insert(name.clone());
+              info
+                .internal_names
+                .insert(namespace_export_symbol.clone(), name.clone());
+              top_level_declarations.insert(name.clone());
+            }
+          }
+
           // Handle namespaceObjectName for concatenated type
           let namespace_object_name =
             if let Some(ref namespace_export_symbol) = info.namespace_export_symbol {

crates/rspack_core/src/external_module.rs

@@ -287,13 +287,22 @@ impl ExternalModule {
                 )
                 .boxed(),
               );
-              format!(
-                r#"
-{} = __WEBPACK_EXTERNAL_MODULE_{}__;
-"#,
-                get_namespace_object_export(concatenation_scope, supports_const),
-                id.clone()
-              )
+
+              if let Some(concatenation_scope) = concatenation_scope {
+                let external_module_id = format!("__WEBPACK_EXTERNAL_MODULE_{}__", id);
+                let namespace_export_with_name =
+                  format!("{}{}", NAMESPACE_OBJECT_EXPORT, &external_module_id);
+                concatenation_scope.register_namespace_export(&namespace_export_with_name);
+                String::new()
+              } else {
+                format!(
+                  r#"
+  {} = __WEBPACK_EXTERNAL_MODULE_{}__;
+  "#,
+                  get_namespace_object_export(concatenation_scope, supports_const),
+                  id.clone()
+                )
+              }
             } else {
               format!(
                 "{} = {};",

packages/rspack-test-tools/etc/api.md

@@ -1134,7 +1134,7 @@ export function parseModules(content: string, options?: {
 };
 
 // @public (undocumented)
-export function readConfigFile<T extends ECompilerType>(files: string[]): TCompilerOptions<T>[];
+export function readConfigFile<T extends ECompilerType>(files: string[], functionApply?: (config: (TCompilerOptions<T> | ((...args: unknown[]) => TCompilerOptions<T>))[]) => TCompilerOptions<T>[]): TCompilerOptions<T>[];
 
 // @public (undocumented)
 export function replaceModuleArgument(raw: string): string;

packages/rspack-test-tools/src/helper/read-config-file.ts

@@ -3,9 +3,16 @@ import fs from "fs-extra";
 import type { ECompilerType, TCompilerOptions } from "../type";
 
 export function readConfigFile<T extends ECompilerType>(
-	files: string[]
+	files: string[],
+	functionApply?: (
+		config: (
+			| TCompilerOptions<T>
+			| ((...args: unknown[]) => TCompilerOptions<T>)
+		)[]
+	) => TCompilerOptions<T>[]
 ): TCompilerOptions<T>[] {
 	const existsFile = files.find(i => fs.existsSync(i));
 	const fileConfig = existsFile ? require(existsFile) : {};
-	return Array.isArray(fileConfig) ? fileConfig : [fileConfig];
+	const configArr = Array.isArray(fileConfig) ? fileConfig : [fileConfig];
+	return functionApply ? functionApply(configArr) : configArr;
 }

packages/rspack-test-tools/src/processor/multi.ts

@@ -92,7 +92,21 @@ export class MultiTaskProcessor<T extends ECompilerType>
 			this._multiOptions.configFiles
 		)
 			? readConfigFile(
-					this._multiOptions.configFiles!.map(i => context.getSource(i))
+					this._multiOptions.configFiles!.map(i => context.getSource(i)),
+					configs => {
+						return configs.flatMap(c => {
+							if (typeof c === "function") {
+								const options = {
+									testPath: context.getDist(),
+									env: undefined
+								};
+
+								return c(options.env, options) as TCompilerOptions<T>;
+							}
+
+							return c as TCompilerOptions<T>;
+						});
+					}
 				)
 			: [{}];
 

packages/rspack-test-tools/tests/configCases/externals/0-concatenation-tree-shaking/externals/m.mjs

@@ -0,0 +1,4 @@
+export const m1 = 11111;
+export const m2 = 22222;
+
+export const m1Add = () => m1++;

packages/rspack-test-tools/tests/configCases/externals/0-concatenation-tree-shaking/index.js

@@ -0,0 +1,3 @@
+import { m1, m2, m1Add } from "./externals/m.mjs";
+
+export { m1, m2, m1Add }

packages/rspack-test-tools/tests/configCases/externals/0-concatenation-tree-shaking/rspack.config.js

@@ -0,0 +1,23 @@
+const rspack = require("@rspack/core");
+
+/** @type {import("@rspack/core").Configuration} */
+module.exports = {
+	externals: [/\.\/externals\/.*/],
+	externalsType: "module",
+	output: {
+		module: true,
+		chunkFormat: "module",
+		filename: "[name].mjs",
+		library: {
+			type: "modern-module",
+		}
+	},
+	experiments: {
+		outputModule: true
+	},
+	plugins: [
+		new rspack.CopyRspackPlugin({
+      patterns: ["./externals/**/*"],
+    }),
+	]
+};

packages/rspack-test-tools/tests/configCases/externals/0-concatenation-tree-shaking/test.config.js

@@ -0,0 +1 @@
+exports.noTests = true;

packages/rspack-test-tools/tests/configCases/externals/1-concatenation-tree-shaking/consume.js

@@ -0,0 +1,3 @@
+import { m1Add } from 'library'
+
+m1Add()

packages/rspack-test-tools/tests/configCases/externals/1-concatenation-tree-shaking/index.js

@@ -0,0 +1,7 @@
+import fs from "fs";
+import path from "path";
+
+it("static import from external module should be tree shaking friendly", () => {
+	const content = fs.readFileSync(path.resolve(__dirname, "consume.mjs"), "utf-8");
+	expect(content).not.toContain("22222");
+});

packages/rspack-test-tools/tests/configCases/externals/1-concatenation-tree-shaking/rspack.config.js

@@ -0,0 +1,38 @@
+const { rspack } = require("@rspack/core");
+const path = require("path");
+
+/** @type {function(any, any): import("@rspack/core").Configuration[]} */
+module.exports = (env, { testPath }) => {
+	return {
+		entry: {
+			consume: "./consume.js",
+			main: "./index.js"
+		},
+		resolve: {
+			alias: {
+				library: path.resolve(testPath, "../0-concatenation-tree-shaking/main.mjs")
+			}
+		},
+		output: {
+			module: true,
+			chunkFormat: "module",
+			filename: "[name].mjs"
+		},
+		experiments: {
+			outputModule: true
+		},
+		optimization: {
+			minimize: true,
+			concatenateModules: true,
+		},
+		plugins: [
+			new rspack.SwcJsMinimizerRspackPlugin({
+				minimizerOptions: {
+					minify: false,
+					mangle: false
+				}
+			})
+		]
+};
+}
+

packages/rspack-test-tools/tests/configCases/externals/1-concatenation-tree-shaking/test.config.js

@@ -0,0 +1,6 @@
+/** @type {import("../../../../dist").TConfigCaseConfig} */
+module.exports = {
+	findBundle: (i, options) => {
+		return ["main.mjs"];
+	}
+};

packages/rspack-test-tools/tests/configCases/library/modern-module-export-char/rspack.config.js

@@ -29,8 +29,8 @@ module.exports = {
 				compilation.hooks.afterProcessAssets.tap("testcase", assets => {
 					const bundle = Object.values(assets)[0]._value
 					expect(bundle).toContain(`var __webpack_exports__cjsInterop = (foo_default());
-var __webpack_exports__defaultImport = external_external_module_namespaceObject["default"];
-var __webpack_exports__namedImport = external_external_module_namespaceObject.namedImport;`)
+var __webpack_exports__defaultImport = __WEBPACK_EXTERNAL_MODULE_external_module__["default"];
+var __webpack_exports__namedImport = __WEBPACK_EXTERNAL_MODULE_external_module__.namedImport;`)
 				});
 			};
 			this.hooks.compilation.tap("testcase", handler);