fix: return to namespace import when the external request includes a specific export (#20126)

lib/ExternalModule.js

@@ -443,10 +443,6 @@ const getSourceForModuleExternal = (
 	dependencyMeta,
 	concatenationScope
 ) => {
-	if (!Array.isArray(moduleAndSpecifiers)) {
-		moduleAndSpecifiers = [moduleAndSpecifiers];
-	}
-
 	/** @type {Imported} */
 	let imported = true;
 	if (concatenationScope) {
@@ -466,6 +462,15 @@ const getSourceForModuleExternal = (
 		}
 	}
 
+	if (!Array.isArray(moduleAndSpecifiers)) {
+		moduleAndSpecifiers = [moduleAndSpecifiers];
+	}
+
+	// Return to `namespace` when the external request includes a specific export
+	if (moduleAndSpecifiers.length > 1) {
+		imported = true;
+	}
+
 	const initFragment = new ModuleExternalInitFragment(
 		moduleAndSpecifiers[0],
 		imported,

test/configCases/library/module-external-array-request/external.mjs

@@ -0,0 +1,4 @@
+export const inner = {
+	foo: "foo",
+	bar: "bar"
+};

test/configCases/library/module-external-array-request/index.js

@@ -0,0 +1,6 @@
+import { foo, bar } from "external";
+
+it("should have the correct export for array-style external request (e.g. external: ['./external.mjs', 'inner'])", function () {
+	expect(foo).toBe("foo");
+	expect(bar).toBe("bar");
+});

test/configCases/library/module-external-array-request/webpack.config.js

@@ -0,0 +1,48 @@
+"use strict";
+
+const fs = require("fs");
+const path = require("path");
+const webpack = require("../../../../");
+
+/** @type {webpack.Configuration} */
+module.exports = {
+	mode: "production",
+	entry: "./index.js",
+	output: {
+		module: true,
+		library: {
+			type: "module"
+		}
+	},
+	experiments: {
+		outputModule: true
+	},
+	externals: {
+		external: ["./external.mjs", "inner"]
+	},
+	externalsType: "module",
+	plugins: [
+		{
+			apply(compiler) {
+				compiler.hooks.compilation.tap("Test", (compilation) => {
+					compilation.hooks.processAssets.tap(
+						{
+							name: "copy-webpack-plugin",
+							stage:
+								compiler.webpack.Compilation.PROCESS_ASSETS_STAGE_ADDITIONAL
+						},
+						() => {
+							const data = fs.readFileSync(
+								path.resolve(__dirname, "./external.mjs")
+							);
+							compilation.emitAsset(
+								"external.mjs",
+								new webpack.sources.RawSource(data)
+							);
+						}
+					);
+				});
+			}
+		}
+	]
+};