Properly construct namespace when dynamically importing chunks with f…

…acades in default export mode (#3709)

src/Chunk.ts

@@ -1081,7 +1081,10 @@ export default class Chunk {
 					if (chunk === this) {
 						node.setInternalResolution(resolution.namespace);
 					} else {
-						node.setExternalResolution(chunk!.exportMode, resolution);
+						node.setExternalResolution(
+							this.facadeChunkByModule.get(resolution)?.exportMode || chunk!.exportMode,
+							resolution
+						);
 					}
 				} else {
 					node.setExternalResolution('auto', resolution);

test/function/samples/dynamic-import-default-mode-facade/_config.js

@@ -0,0 +1,11 @@
+const assert = require('assert');
+
+module.exports = {
+	description: 'handles dynamic imports from facades using default export mode',
+	options: {
+		input: ['main', 'foo', 'bar']
+	},
+	exports(exports) {
+		return exports.then(exported => assert.deepStrictEqual(exported, { default: 4 }));
+	}
+};

test/function/samples/dynamic-import-default-mode-facade/bar.js

@@ -0,0 +1,3 @@
+import foo from './foo.js';
+import square from './square.js';
+export default square(3) + foo;

test/function/samples/dynamic-import-default-mode-facade/foo.js

@@ -0,0 +1,2 @@
+import square from './square.js';
+export default square(2);

test/function/samples/dynamic-import-default-mode-facade/main.js

@@ -0,0 +1 @@
+export default import('./foo.js');

test/function/samples/dynamic-import-default-mode-facade/square.js

@@ -0,0 +1 @@
+export default x => x * x;