Merge pull request #12002 from webpack/bugfix/ns-consistency

make visible exports from non-harmony modules more consistent
webpack · Nov 17, 2020 · a17ad8e · a17ad8e
2 parents 5f686b6 + ac15f06
commit a17ad8e
Show file tree

Hide file tree

Showing 15 changed files with 432 additions and 84 deletions.
diff --git a/lib/ContextModule.js b/lib/ContextModule.js
@@ -553,18 +553,26 @@ class ContextModule extends Module {
 			: "";
 	}
 
-	getReturn(type) {
+	getReturn(type, asyncModule) {
 		if (type === 9) {
 			return "__webpack_require__(id)";
 		}
-		return `${RuntimeGlobals.createFakeNamespaceObject}(id, ${type})`;
+		return `${RuntimeGlobals.createFakeNamespaceObject}(id, ${type}${
+			asyncModule ? " | 16" : ""
+		})`;
 	}
 
-	getReturnModuleObjectSource(fakeMap, fakeMapDataExpression = "fakeMap[id]") {
+	getReturnModuleObjectSource(
+		fakeMap,
+		asyncModule,
+		fakeMapDataExpression = "fakeMap[id]"
+	) {
 		if (typeof fakeMap === "number") {
 			return `return ${this.getReturn(fakeMap)};`;
 		}
-		return `return ${RuntimeGlobals.createFakeNamespaceObject}(id, ${fakeMapDataExpression})`;
+		return `return ${
+			RuntimeGlobals.createFakeNamespaceObject
+		}(id, ${fakeMapDataExpression}${asyncModule ? " | 16" : ""})`;
 	}
 
 	/**
@@ -652,7 +660,7 @@ module.exports = webpackContext;`;
 		const arrow = runtimeTemplate.supportsArrowFunction();
 		const map = this.getUserRequestMap(dependencies, chunkGraph);
 		const fakeMap = this.getFakeMap(dependencies, chunkGraph);
-		const returnModuleObject = this.getReturnModuleObjectSource(fakeMap);
+		const returnModuleObject = this.getReturnModuleObjectSource(fakeMap, true);
 
 		return `var map = ${JSON.stringify(map, null, "\t")};
 ${this.getFakeMapInitStatement(fakeMap)}
@@ -755,7 +763,7 @@ module.exports = webpackAsyncContext;`;
 		const thenFunction =
 			fakeMap !== 9
 				? `${arrow ? "id =>" : "function(id)"} {
-		${this.getReturnModuleObjectSource(fakeMap)};
+		${this.getReturnModuleObjectSource(fakeMap, true)};
 	}`
 				: "__webpack_require__";
 
@@ -853,12 +861,13 @@ module.exports = webpackAsyncContext;`;
 			: `${RuntimeGlobals.ensureChunk}(ids[${chunksStartPosition}])`;
 		const returnModuleObject = this.getReturnModuleObjectSource(
 			fakeMap,
+			true,
 			shortMode ? "invalid" : "ids[1]"
 		);
 
 		const webpackAsyncContext =
 			requestPrefix === "Promise.resolve()"
-				? `${shortMode ? "" : ""}
+				? `
 function webpackAsyncContext(req) {
 	return Promise.resolve().then(${arrow ? "() =>" : "function()"} {
 		if(!${RuntimeGlobals.hasOwnProperty}(map, req)) {

diff --git a/lib/RuntimeTemplate.js b/lib/RuntimeTemplate.js
@@ -497,7 +497,7 @@ class RuntimeTemplate {
 			weak
 		});
 		const exportsType = module.getExportsType(chunkGraph.moduleGraph, strict);
-		let fakeType = 0;
+		let fakeType = 16;
 		switch (exportsType) {
 			case "namespace":
 				if (header) {
@@ -745,6 +745,11 @@ class RuntimeTemplate {
 						"/* non-default import from non-esm module */undefined" +
 						propertyAccess(exportName, 1)
 					);
+				} else if (
+					exportsType !== "namespace" &&
+					exportName[0] === "__esModule"
+				) {
+					return "/* __esModule */true";
 				}
 			} else if (
 				exportsType === "default-only" ||

diff --git a/lib/optimize/ConcatenatedModule.js b/lib/optimize/ConcatenatedModule.js
@@ -271,12 +271,29 @@ const getFinalBinding = (
 			case "namespace":
 				break;
 			case "default-with-named":
-				if (exportName[0] === "default") {
-					exportName = exportName.slice(1);
+				switch (exportName[0]) {
+					case "default":
+						exportName = exportName.slice(1);
+						break;
+					case "__esModule":
+						return {
+							info,
+							rawName: "/* __esModule */true",
+							ids: exportName.slice(1),
+							exportName
+						};
 				}
 				break;
 			case "default-only": {
 				const exportId = exportName[0];
+				if (exportId === "__esModule") {
+					return {
+						info,
+						rawName: "/* __esModule */true",
+						ids: exportName.slice(1),
+						exportName
+					};
+				}
 				exportName = exportName.slice(1);
 				if (exportId !== "default") {
 					return {
@@ -290,22 +307,31 @@ const getFinalBinding = (
 				break;
 			}
 			case "dynamic":
-				if (exportName[0] === "default") {
-					exportName = exportName.slice(1);
-					info.interopDefaultAccessUsed = true;
-					const defaultExport = asCall
-						? `${info.interopDefaultAccessName}()`
-						: asiSafe
-						? `(${info.interopDefaultAccessName}())`
-						: asiSafe === false
-						? `;(${info.interopDefaultAccessName}())`
-						: `${info.interopDefaultAccessName}.a`;
-					return {
-						info,
-						rawName: defaultExport,
-						ids: exportName,
-						exportName
-					};
+				switch (exportName[0]) {
+					case "default": {
+						exportName = exportName.slice(1);
+						info.interopDefaultAccessUsed = true;
+						const defaultExport = asCall
+							? `${info.interopDefaultAccessName}()`
+							: asiSafe
+							? `(${info.interopDefaultAccessName}())`
+							: asiSafe === false
+							? `;(${info.interopDefaultAccessName}())`
+							: `${info.interopDefaultAccessName}.a`;
+						return {
+							info,
+							rawName: defaultExport,
+							ids: exportName,
+							exportName
+						};
+					}
+					case "__esModule":
+						return {
+							info,
+							rawName: "/* __esModule */true",
+							ids: exportName.slice(1),
+							exportName
+						};
 				}
 				break;
 			default:

diff --git a/lib/runtime/CreateFakeNamespaceObjectRuntimeModule.js b/lib/runtime/CreateFakeNamespaceObjectRuntimeModule.js
@@ -23,25 +23,37 @@ class CreateFakeNamespaceObjectRuntimeModule extends HelperRuntimeModule {
 			runtimeTemplate.supportsConst();
 		const fn = RuntimeGlobals.createFakeNamespaceObject;
 		return Template.asString([
+			`var getProto = Object.getPrototypeOf ? ${runtimeTemplate.returningFunction(
+				"Object.getPrototypeOf(obj)",
+				"obj"
+			)} : ${runtimeTemplate.returningFunction("obj.__proto__", "obj")};`,
+			"var leafPrototypes;",
 			"// create a fake namespace object",
 			"// mode & 1: value is a module id, require it",
 			"// mode & 2: merge all properties of value into the ns",
 			"// mode & 4: return value when already ns object",
+			"// mode & 16: return value when it's Promise-like",
 			"// mode & 8|1: behave like require",
 			// Note: must be a function (not arrow), because this is used in body!
 			`${fn} = function(value, mode) {`,
 			Template.indent([
 				`if(mode & 1) value = this(value);`,
 				`if(mode & 8) return value;`,
-				"if((mode & 4) && typeof value === 'object' && value && value.__esModule) return value;",
+				"if(typeof value === 'object' && value) {",
+				Template.indent([
+					"if((mode & 4) && value.__esModule) return value;",
+					"if((mode & 16) && typeof value.then === 'function') return value;"
+				]),
+				"}",
 				"var ns = Object.create(null);",
 				`${RuntimeGlobals.makeNamespaceObject}(ns);`,
 				"var def = {};",
-				"if(mode & 2 && typeof value == 'object' && value) {",
+				"leafPrototypes = leafPrototypes || [null, getProto({}), getProto([]), getProto(getProto)];",
+				"for(var current = mode & 2 && value; typeof current == 'object' && !~leafPrototypes.indexOf(current); current = getProto(current)) {",
 				Template.indent([
 					modern
-						? `for(const key in value) def[key] = () => value[key];`
-						: `for(var key in value) def[key] = function(key) { return value[key]; }.bind(null, key);`
+						? `Object.getOwnPropertyNames(current).forEach(key => def[key] = () => value[key]);`
+						: `Object.getOwnPropertyNames(current).forEach(function(key) { def[key] = function() { return value[key]; }; });`
 				]),
 				"}",
 				modern

diff --git a/test/Stats.test.js b/test/Stats.test.js
@@ -173,10 +173,10 @@ describe("Stats", () => {
 			      "assets": Array [
 			        Object {
 			          "name": "entryB.js",
-			          "size": 2706,
+			          "size": 2910,
 			        },
 			      ],
-			      "assetsSize": 2706,
+			      "assetsSize": 2910,
 			      "auxiliaryAssets": undefined,
 			      "auxiliaryAssetsSize": 0,
 			      "childAssets": undefined,
@@ -221,10 +221,10 @@ describe("Stats", () => {
 			      "info": Object {
 			        "javascriptModule": false,
 			        "minimized": true,
-			        "size": 2706,
+			        "size": 2910,
 			      },
 			      "name": "entryB.js",
-			      "size": 2706,
+			      "size": 2910,
 			      "type": "asset",
 			    },
 			    Object {