refactor Parser to allow variable tagging

use variable tagging in harmony pluging (instead of magic renaming)
Parser no longer calls hooks.expression for x in `x = ...`, hooks.pattern is called instead
remove rootName argument from hooks.expressionMemberChain and hooks.callMemberChain

lib/APIPlugin.js

@@ -10,6 +10,7 @@ const {
 	evaluateToString
 } = require("./JavascriptParserHelpers");
 const RuntimeGlobals = require("./RuntimeGlobals");
+const WebpackError = require("./WebpackError");
 const ConstDependency = require("./dependencies/ConstDependency");
 const ChunkNameRuntimeModule = require("./runtime/ChunkNameRuntimeModule");
 const GetFullHashRuntimeModule = require("./runtime/GetFullHashRuntimeModule");
@@ -21,52 +22,62 @@ const REPLACEMENTS = {
 	__webpack_require__: {
 		expr: RuntimeGlobals.require,
 		req: [RuntimeGlobals.require],
-		type: "function"
+		type: "function",
+		assign: false
 	},
 	__webpack_public_path__: {
 		expr: RuntimeGlobals.publicPath,
 		req: [RuntimeGlobals.publicPath],
-		type: "string"
+		type: "string",
+		assign: true
 	},
 	__webpack_modules__: {
 		expr: RuntimeGlobals.moduleFactories,
 		req: [RuntimeGlobals.moduleFactories],
-		type: "object"
+		type: "object",
+		assign: false
 	},
 	__webpack_chunk_load__: {
 		expr: RuntimeGlobals.ensureChunk,
 		req: [RuntimeGlobals.ensureChunk],
-		type: "function"
+		type: "function",
+		assign: true
 	},
 	__non_webpack_require__: {
 		expr: "require",
 		req: null,
-		type: undefined // type is not know, depends on environment
+		type: undefined, // type is not know, depends on environment
+		assign: true
 	},
 	__webpack_nonce__: {
 		expr: RuntimeGlobals.scriptNonce,
 		req: [RuntimeGlobals.scriptNonce],
-		type: "string"
+		type: "string",
+		assign: true
 	},
 	__webpack_hash__: {
 		expr: `${RuntimeGlobals.getFullHash}()`,
 		req: [RuntimeGlobals.getFullHash],
-		type: "string"
+		type: "string",
+		assign: false
 	},
 	__webpack_chunkname__: {
 		expr: RuntimeGlobals.chunkName,
 		req: [RuntimeGlobals.chunkName],
-		type: "string"
+		type: "string",
+		assign: false
 	},
 	__webpack_get_script_filename__: {
 		expr: RuntimeGlobals.getChunkScriptFilename,
 		req: [RuntimeGlobals.getChunkScriptFilename],
-		type: "function"
+		type: "function",
+		assign: true
 	},
 	"require.onError": {
 		expr: RuntimeGlobals.uncaughtErrorHandler,
 		req: [RuntimeGlobals.uncaughtErrorHandler],
-		type: undefined // type is not know, could be function or undefined
+		type: undefined, // type is not know, could be function or undefined
+		assign: true // is never a pattern
 	}
 };
 /* eslint-enable camelcase */
@@ -112,6 +123,13 @@ class APIPlugin {
 								"APIPlugin",
 								toConstantDependency(parser, info.expr, info.req)
 							);
+						if (info.assign === false) {
+							parser.hooks.assign.for(key).tap("APIPlugin", expr => {
+								const err = new WebpackError(`${key} must not be assigned`);
+								err.loc = expr.loc;
+								throw err;
+							});
+						}
 						if (info.type) {
 							parser.hooks.evaluateTypeof
 								.for(key)

lib/BasicEvaluatedExpression.js

@@ -21,22 +21,25 @@ const TypeTemplateString = 11;
 class BasicEvaluatedExpression {
 	constructor() {
 		this.type = TypeUnknown;
-		this.range = null;
+		this.range = undefined;
 		this.falsy = false;
 		this.truthy = false;
-		this.bool = null;
-		this.number = null;
-		this.regExp = null;
-		this.string = null;
-		this.quasis = null;
-		this.parts = null;
-		this.array = null;
-		this.items = null;
-		this.options = null;
-		this.prefix = null;
-		this.postfix = null;
-		this.wrappedInnerExpressions = null;
-		this.expression = null;
+		this.bool = undefined;
+		this.number = undefined;
+		this.regExp = undefined;
+		this.string = undefined;
+		this.quasis = undefined;
+		this.parts = undefined;
+		this.array = undefined;
+		this.items = undefined;
+		this.options = undefined;
+		this.prefix = undefined;
+		this.postfix = undefined;
+		this.wrappedInnerExpressions = undefined;
+		this.identifier = undefined;
+		this.rootInfo = undefined;
+		this.getMembers = undefined;
+		this.expression = undefined;
 	}
 
 	isNull() {
@@ -171,9 +174,11 @@ class BasicEvaluatedExpression {
 		return this;
 	}
 
-	setIdentifier(identifier) {
+	setIdentifier(identifier, rootInfo, getMembers) {
 		this.type = TypeIdentifier;
 		this.identifier = identifier;
+		this.rootInfo = rootInfo;
+		this.getMembers = getMembers;
 		return this;
 	}
 

lib/CommonJsStuffPlugin.js

@@ -143,7 +143,7 @@ class CommonJsStuffPlugin {
 						.for("module.hot")
 						.tap(
 							"CommonJsStuffPlugin",
-							evaluateToIdentifier("module.hot", false)
+							evaluateToIdentifier("module.hot", "module", () => ["hot"], false)
 						);
 					parser.hooks.expression
 						.for("module")

lib/CompatibilityPlugin.js

@@ -10,6 +10,8 @@ const ConstDependency = require("./dependencies/ConstDependency");
 /** @typedef {import("./Compiler")} Compiler */
 /** @typedef {import("./JavascriptParser")} JavascriptParser */
 
+const nestedWebpackRequireTag = Symbol("nested __webpack_require__");
+
 class CompatibilityPlugin {
 	/**
 	 * Apply the plugin
@@ -75,23 +77,17 @@ class CompatibilityPlugin {
 							const dep = new ConstDependency(newName, pattern.range);
 							dep.loc = pattern.loc;
 							parser.state.current.addDependency(dep);
-							parser.scope.renames.set(
+							parser.tagVariable(
 								pattern.name,
-								"nested __webpack_require__"
-							);
-							parser.scope.renames.set(
-								"nested __webpack_require__ name",
+								nestedWebpackRequireTag,
 								newName
 							);
-							parser.scope.definitions.delete(pattern.name);
 							return true;
 						});
 					parser.hooks.expression
-						.for("nested __webpack_require__")
+						.for(nestedWebpackRequireTag)
 						.tap("CompatibilityPlugin", expr => {
-							const newName = parser.scope.renames.get(
-								"nested __webpack_require__ name"
-							);
+							const newName = parser.currentTagData;
 							const dep = new ConstDependency(newName, expr.range);
 							dep.loc = expr.loc;
 							parser.state.current.addDependency(dep);

lib/ExportsInfoApiPlugin.js

@@ -31,7 +31,7 @@ class ExportsInfoApiPlugin {
 				const handler = parser => {
 					parser.hooks.expressionMemberChain
 						.for("__webpack_exports_info__")
-						.tap("ExportsInfoApiPlugin", (expr, rootRaw, members) => {
+						.tap("ExportsInfoApiPlugin", (expr, members) => {
 							const dep =
 								members.length >= 2
 									? new ExportsInfoDependency(

lib/HotModuleReplacementPlugin.js

@@ -108,7 +108,12 @@ class HotModuleReplacementPlugin {
 					before: "NodeStuffPlugin"
 				},
 				expr => {
-					return evaluateToIdentifier("module.hot", true)(expr);
+					return evaluateToIdentifier(
+						"module.hot",
+						"module",
+						() => ["hot"],
+						true
+					)(expr);
 				}
 			);
 			parser.hooks.call

lib/JavascriptParserHelpers.js

@@ -32,10 +32,10 @@ exports.evaluateToBoolean = value => {
 	};
 };
 
-exports.evaluateToIdentifier = (identifier, truthy) => {
+exports.evaluateToIdentifier = (identifier, rootInfo, getMembers, truthy) => {
 	return function identifierExpression(expr) {
 		let evex = new BasicEvaluatedExpression()
-			.setIdentifier(identifier)
+			.setIdentifier(identifier, rootInfo, getMembers)
 			.setRange(expr.range);
 		if (truthy === true) {
 			evex = evex.setTruthy();

lib/dependencies/AMDDefineDependencyParserPlugin.js

@@ -228,7 +228,7 @@ class AMDDefineDependencyParserPlugin {
 				}
 			}
 		}
-		let fnRenames = parser.scope.renames.createChild();
+		let fnRenames = new Map();
 		if (array) {
 			const identifiers = {};
 			const param = parser.evaluateExpression(array);
@@ -243,7 +243,7 @@ class AMDDefineDependencyParserPlugin {
 			if (fnParams) {
 				fnParams = fnParams.slice(fnParamsOffset).filter((param, idx) => {
 					if (identifiers[idx]) {
-						fnRenames.set(param.name, identifiers[idx]);
+						fnRenames.set(param.name, parser.getVariableInfo(identifiers[idx]));
 						return false;
 					}
 					return true;
@@ -254,7 +254,7 @@ class AMDDefineDependencyParserPlugin {
 			if (fnParams) {
 				fnParams = fnParams.slice(fnParamsOffset).filter((param, idx) => {
 					if (identifiers[idx]) {
-						fnRenames.set(param.name, identifiers[idx]);
+						fnRenames.set(param.name, parser.getVariableInfo(identifiers[idx]));
 						return false;
 					}
 					return true;
@@ -265,7 +265,9 @@ class AMDDefineDependencyParserPlugin {
 		if (fn && isUnboundFunctionExpression(fn)) {
 			inTry = parser.scope.inTry;
 			parser.inScope(fnParams, () => {
-				parser.scope.renames = fnRenames;
+				for (const [name, varInfo] of fnRenames) {
+					parser.setVariable(name, varInfo);
+				}
 				parser.scope.inTry = inTry;
 				if (fn.body.type === "BlockStatement") {
 					parser.walkStatement(fn.body);
@@ -280,7 +282,9 @@ class AMDDefineDependencyParserPlugin {
 					i => !["require", "module", "exports"].includes(i.name)
 				),
 				() => {
-					parser.scope.renames = fnRenames;
+					for (const [name, varInfo] of fnRenames) {
+						parser.setVariable(name, varInfo);
+					}
 					parser.scope.inTry = inTry;
 					if (fn.callee.object.body.type === "BlockStatement") {
 						parser.walkStatement(fn.callee.object.body);

lib/dependencies/AMDPlugin.js

@@ -124,7 +124,7 @@ class AMDPlugin {
 				const handler = (parser, parserOptions) => {
 					if (parserOptions.amd !== undefined && !parserOptions.amd) return;
 
-					const tapOptionsHooks = optionExpr => {
+					const tapOptionsHooks = (optionExpr, rootName, getMembers) => {
 						parser.hooks.expression
 							.for(optionExpr)
 							.tap(
@@ -135,7 +135,10 @@ class AMDPlugin {
 							);
 						parser.hooks.evaluateIdentifier
 							.for(optionExpr)
-							.tap("AMDPlugin", evaluateToIdentifier(optionExpr, true));
+							.tap(
+								"AMDPlugin",
+								evaluateToIdentifier(optionExpr, rootName, getMembers, true)
+							);
 						parser.hooks.evaluateTypeof
 							.for(optionExpr)
 							.tap("AMDPlugin", evaluateToString("object"));
@@ -150,9 +153,13 @@ class AMDPlugin {
 					new AMDRequireDependenciesBlockParserPlugin(options).apply(parser);
 					new AMDDefineDependencyParserPlugin(options).apply(parser);
 
-					tapOptionsHooks("define.amd");
-					tapOptionsHooks("require.amd");
-					tapOptionsHooks("__webpack_amd_options__");
+					tapOptionsHooks("define.amd", "define", () => "amd");
+					tapOptionsHooks("require.amd", "require", () => ["amd"]);
+					tapOptionsHooks(
+						"__webpack_amd_options__",
+						"__webpack_amd_options__",
+						() => []
+					);
 
 					parser.hooks.expression.for("define").tap("AMDPlugin", expr => {
 						const dep = new ConstDependency(

lib/dependencies/CommonJsPlugin.js

@@ -84,12 +84,7 @@ class CommonJsPlugin {
 					if (parserOptions.commonjs !== undefined && !parserOptions.commonjs)
 						return;
 
-					const requireExpressions = [
-						"require",
-						"require.resolve",
-						"require.resolveWeak"
-					];
-					for (let expression of requireExpressions) {
+					const tapRequireExpression = (expression, getMembers) => {
 						parser.hooks.typeof
 							.for(expression)
 							.tap(
@@ -101,8 +96,14 @@ class CommonJsPlugin {
 							.tap("CommonJsPlugin", evaluateToString("function"));
 						parser.hooks.evaluateIdentifier
 							.for(expression)
-							.tap("CommonJsPlugin", evaluateToIdentifier(expression, true));
-					}
+							.tap(
+								"CommonJsPlugin",
+								evaluateToIdentifier(expression, "require", getMembers, true)
+							);
+					};
+					tapRequireExpression("require", () => []);
+					tapRequireExpression("require.resolve", () => ["resolve"]);
+					tapRequireExpression("require.resolveWeak", () => ["resolveWeak"]);
 
 					parser.hooks.evaluateTypeof
 						.for("module")
@@ -121,15 +122,14 @@ class CommonJsPlugin {
 						const dep = new ConstDependency("var require;", 0);
 						dep.loc = expr.loc;
 						parser.state.current.addDependency(dep);
-						parser.scope.definitions.add("require");
 						return true;
 					});
 					parser.hooks.canRename
 						.for("require")
 						.tap("CommonJsPlugin", () => true);
 					parser.hooks.rename.for("require").tap("CommonJsPlugin", expr => {
-						// define the require variable. It's still undefined, but not "not defined".
-						const dep = new ConstDependency("var require;", 0);
+						// To avoid "not defined" error, replace the value with undefined
+						const dep = new ConstDependency("undefined", expr.range);
 						dep.loc = expr.loc;
 						parser.state.current.addDependency(dep);
 						return false;

lib/dependencies/HarmonyExportDependencyParserPlugin.js

@@ -11,6 +11,8 @@ const HarmonyExportHeaderDependency = require("./HarmonyExportHeaderDependency")
 const HarmonyExportImportedSpecifierDependency = require("./HarmonyExportImportedSpecifierDependency");
 const HarmonyExportSpecifierDependency = require("./HarmonyExportSpecifierDependency");
 const HarmonyImportSideEffectDependency = require("./HarmonyImportSideEffectDependency");
+const harmonySpecifierTag = require("./HarmonyImportDependencyParserPlugin")
+	.harmonySpecifierTag;
 
 module.exports = class HarmonyExportDependencyParserPlugin {
 	constructor(options) {
@@ -93,13 +95,12 @@ module.exports = class HarmonyExportDependencyParserPlugin {
 		parser.hooks.exportSpecifier.tap(
 			"HarmonyExportDependencyParserPlugin",
 			(statement, id, name, idx) => {
-				const rename = parser.scope.renames.get(id);
+				const settings = parser.getTagData(id, harmonySpecifierTag);
 				let dep;
 				const harmonyNamedExports = (parser.state.harmonyNamedExports =
 					parser.state.harmonyNamedExports || new Set());
 				harmonyNamedExports.add(name);
-				if (rename === "imported var") {
-					const settings = parser.state.harmonySpecifier.get(id);
+				if (settings) {
 					dep = new HarmonyExportImportedSpecifierDependency(
 						settings.source,
 						settings.sourceOrder,

lib/dependencies/HarmonyImportDependencyParserPlugin.js

@@ -12,6 +12,8 @@ const HarmonyAcceptImportDependency = require("./HarmonyAcceptImportDependency")
 const HarmonyImportSideEffectDependency = require("./HarmonyImportSideEffectDependency");
 const HarmonyImportSpecifierDependency = require("./HarmonyImportSpecifierDependency");
 
+const harmonySpecifierTag = Symbol("harmony import");
+
 module.exports = class HarmonyImportDependencyParserPlugin {
 	constructor(options) {
 		const { module: moduleOptions } = options;
@@ -47,13 +49,9 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 		parser.hooks.importSpecifier.tap(
 			"HarmonyImportDependencyParserPlugin",
 			(statement, source, id, name) => {
-				parser.scope.definitions.delete(name);
-				parser.scope.renames.set(name, "imported var");
-				if (!parser.state.harmonySpecifier) {
-					parser.state.harmonySpecifier = new Map();
-				}
 				const ids = id === null ? [] : [id];
-				parser.state.harmonySpecifier.set(name, {
+				parser.tagVariable(name, harmonySpecifierTag, {
+					name,
 					source,
 					ids,
 					sourceOrder: parser.state.lastHarmonyImportOrder,
@@ -63,15 +61,14 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 			}
 		);
 		parser.hooks.expression
-			.for("imported var")
+			.for(harmonySpecifierTag)
 			.tap("HarmonyImportDependencyParserPlugin", expr => {
-				const name = expr.name;
-				const settings = parser.state.harmonySpecifier.get(name);
+				const settings = parser.currentTagData;
 				const dep = new HarmonyImportSpecifierDependency(
 					settings.source,
 					settings.sourceOrder,
 					settings.ids,
-					name,
+					settings.name,
 					expr.range,
 					this.strictExportPresence
 				);
@@ -84,15 +81,15 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 				return true;
 			});
 		parser.hooks.expressionMemberChain
-			.for("imported var")
-			.tap("HarmonyImportDependencyParserPlugin", (expr, name, members) => {
-				const settings = parser.state.harmonySpecifier.get(name);
+			.for(harmonySpecifierTag)
+			.tap("HarmonyImportDependencyParserPlugin", (expr, members) => {
+				const settings = parser.currentTagData;
 				const ids = settings.ids.concat(members);
 				const dep = new HarmonyImportSpecifierDependency(
 					settings.source,
 					settings.sourceOrder,
 					ids,
-					name,
+					settings.name,
 					expr.range,
 					this.strictExportPresence
 				);
@@ -103,17 +100,17 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 				return true;
 			});
 		parser.hooks.callMemberChain
-			.for("imported var")
-			.tap("HarmonyImportDependencyParserPlugin", (expr, name, members) => {
+			.for(harmonySpecifierTag)
+			.tap("HarmonyImportDependencyParserPlugin", (expr, members) => {
 				const args = expr.arguments;
 				expr = expr.callee;
-				const settings = parser.state.harmonySpecifier.get(name);
+				const settings = parser.currentTagData;
 				const ids = settings.ids.concat(members);
 				const dep = new HarmonyImportSpecifierDependency(
 					settings.source,
 					settings.sourceOrder,
 					ids,
-					name,
+					settings.name,
 					expr.range,
 					this.strictExportPresence
 				);
@@ -183,3 +180,5 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 		);
 	}
 };
+
+module.exports.harmonySpecifierTag = harmonySpecifierTag;

lib/dependencies/HarmonyImportSpecifierDependency.js

@@ -203,14 +203,12 @@ HarmonyImportSpecifierDependency.Template = class HarmonyImportSpecifierDependen
 	apply(dependency, source, templateContext) {
 		super.apply(dependency, source, templateContext);
 		const dep = /** @type {HarmonyImportSpecifierDependency} */ (dependency);
-		const content = this.getContent(dep, templateContext);
-		source.replace(dep.range[0], dep.range[1] - 1, content);
-	}
-
-	getContent(
-		dep,
-		{ runtimeTemplate, module, moduleGraph, runtimeRequirements }
-	) {
+		const {
+			runtimeTemplate,
+			module,
+			moduleGraph,
+			runtimeRequirements
+		} = templateContext;
 		const ids = dep.getIds(moduleGraph);
 		const exportExpr = runtimeTemplate.exportFromImport({
 			moduleGraph,
@@ -224,7 +222,11 @@ HarmonyImportSpecifierDependency.Template = class HarmonyImportSpecifierDependen
 			importVar: dep.getImportVar(moduleGraph),
 			runtimeRequirements
 		});
-		return dep.shorthand ? `${dep.name}: ${exportExpr}` : exportExpr;
+		if (dep.shorthand) {
+			source.insert(dep.range[1], `: ${exportExpr}`);
+		} else {
+			source.replace(dep.range[0], dep.range[1] - 1, exportExpr);
+		}
 	}
 };
 

lib/optimize/ConcatenatedModule.js

@@ -1392,9 +1392,10 @@ class HarmonyImportSpecifierDependencyConcatenatedTemplate extends DependencyTem
 			});
 		}
 		if (dep.shorthand) {
-			content = dep.name + ": " + content;
+			source.insert(dep.range[1], ": " + content);
+		} else {
+			source.replace(dep.range[0], dep.range[1] - 1, content);
 		}
-		source.replace(dep.range[0], dep.range[1] - 1, content);
 	}
 }
 

lib/util/StackedSetMap.js

@@ -40,7 +40,7 @@ const extractPair = pair => {
  */
 class StackedSetMap {
 	/**
-	 * @param {Map<K, V>[]=} parentStack an optional parent
+	 * @param {Map<K, InternalCell<V>>[]=} parentStack an optional parent
 	 */
 	constructor(parentStack) {
 		/** @type {Map<K, InternalCell<V>>} */

test/cases/loaders/css-loader/index.js

@@ -1,11 +1,11 @@
 it("should handle the css loader correctly", function() {
-	expect(
-        (require("!css-loader!../_css/stylesheet.css") + "").indexOf(".rule-direct")
-    ).not.toEqual(-1);
-	expect(
-        (require("!css-loader!../_css/stylesheet.css") + "").indexOf(".rule-import1")
-    ).not.toEqual(-1);
-	expect(
-        (require("!css-loader!../_css/stylesheet.css") + "").indexOf(".rule-import2")
-    ).not.toEqual(-1);
+	expect(require("!css-loader!../_css/stylesheet.css") + "").toContain(
+		".rule-direct"
+	);
+	expect(require("!css-loader!../_css/stylesheet.css") + "").toContain(
+		".rule-import1"
+	);
+	expect(require("!css-loader!../_css/stylesheet.css") + "").toContain(
+		".rule-import2"
+	);
 });

test/cases/parsing/context/index.js

@@ -5,7 +5,7 @@ it("should be able to load a file with the require.context method", function() {
 	expect(require.context("./loaders/queryloader?dog=bark!./templates?cat=meow")("./tmpl")).toEqual({
 		resourceQuery: "?cat=meow",
 		query: "?dog=bark",
-		prev: "module.exports = \"test template\";"
+		prev: 'module.exports = "test template";'
 	});
 	expect(require . context ( "." + "/." + "/" + "templ" + "ates" ) ( "./subdir/tmpl.js" )).toBe("subdir test template");
 	expect(require.context("./templates", true, /./)("xyz")).toBe("xyz");
@@ -22,13 +22,13 @@ it("should automatically create contexts", function() {
 
 it("should be able to require.resolve with automatical context", function() {
 	var template = "tmpl";
-	expect(require.resolve("./templates/" + template)).toBe(require.resolve("./templates/tmpl"));
+	expect(require.resolve("./templates/" + template)).toBe(
+		require.resolve("./templates/tmpl")
+	);
 });
 
 it("should be able to use renaming combined with a context", function() {
 	var renamedRequire = require;
-	require = function () {};
-	require("fail");
 	var template = "tmpl";
 	expect(renamedRequire("./templates/" + template)).toBe("test template");
 });