support context in Dependency

lib/Compilation.js

@@ -1436,7 +1436,7 @@ BREAKING CHANGE: Asset processing hooks in Compilation has been merged into a si
 	 * @returns {void}
 	 */
 	_processModuleDependencies(module, callback) {
-		/** @type {Array<{factory: ModuleFactory, dependencies: Dependency[], originModule: Module|null}>} */
+		/** @type {Array<{factory: ModuleFactory, dependencies: Dependency[], context: string|undefined, originModule: Module|null}>} */
 		const sortedDependencies = [];
 
 		/** @type {DependenciesBlock} */
@@ -1668,6 +1668,7 @@ BREAKING CHANGE: Asset processing hooks in Compilation has been merged into a si
 					sortedDependencies.push({
 						factory: factoryCacheKey2,
 						dependencies: list,
+						context: dep.getContext(),
 						originModule: module
 					});
 				}

lib/ContextModuleFactory.js

@@ -292,7 +292,6 @@ module.exports = class ContextModuleFactory extends ModuleFactory {
 		} = options;
 		if (!regExp || !resource) return callback(null, []);
 
-		let severalContexts = false;
 		const addDirectoryChecked = (ctx, directory, visited, callback) => {
 			fs.realpath(directory, (err, realPath) => {
 				if (err) return callback(err);
@@ -359,15 +358,13 @@ module.exports = class ContextModuleFactory extends ModuleFactory {
 											alternatives = alternatives
 												.filter(obj => regExp.test(obj.request))
 												.map(obj => {
-													const request = severalContexts
-														? join(fs, obj.context, obj.request)
-														: obj.request;
 													const dep = new ContextElementDependency(
-														request + resourceQuery + resourceFragment,
+														`${obj.request}${resourceQuery}${resourceFragment}`,
 														obj.request,
 														typePrefix,
 														category,
-														referencedExports
+														referencedExports,
+														obj.context
 													);
 													dep.optional = true;
 													return dep;
@@ -414,7 +411,6 @@ module.exports = class ContextModuleFactory extends ModuleFactory {
 		if (typeof resource === "string") {
 			visitResource(resource, callback);
 		} else {
-			severalContexts = true;
 			asyncLib.map(resource, visitResource, (err, result) => {
 				if (err) return callback(err);
 

lib/Dependency.js

@@ -182,6 +182,13 @@ class Dependency {
 		this._loc = undefined;
 	}
 
+	/**
+	 * @returns {string | undefined} a request context
+	 */
+	getContext() {
+		return undefined;
+	}
+
 	/**
 	 * @returns {string | null} an identifier to merge equal requests
 	 */

lib/dependencies/ContextElementDependency.js

@@ -14,11 +14,27 @@ const ModuleDependency = require("./ModuleDependency");
 /** @typedef {import("../util/runtime").RuntimeSpec} RuntimeSpec */
 
 class ContextElementDependency extends ModuleDependency {
-	constructor(request, userRequest, typePrefix, category, referencedExports) {
+	/**
+	 * @param {string} request request
+	 * @param {string|undefined} userRequest user request
+	 * @param {string} typePrefix type prefix
+	 * @param {string} category category
+	 * @param {string[][]=} referencedExports referenced exports
+	 * @param {string=} context context
+	 */
+	constructor(
+		request,
+		userRequest,
+		typePrefix,
+		category,
+		referencedExports,
+		context
+	) {
 		super(request);
 		this.referencedExports = referencedExports;
 		this._typePrefix = typePrefix;
 		this._category = category;
+		this._context = context || undefined;
 
 		if (userRequest) {
 			this.userRequest = userRequest;
@@ -33,6 +49,17 @@ class ContextElementDependency extends ModuleDependency {
 		return "context element";
 	}
 
+	/**
+	 * @returns {string | undefined} a request context
+	 */
+	getContext() {
+		return this._context;
+	}
+
+	getResourceIdentifier() {
+		return `context${this._context || ""}|${super.getResourceIdentifier()}`;
+	}
+
 	get category() {
 		return this._category;
 	}
@@ -56,6 +83,7 @@ class ContextElementDependency extends ModuleDependency {
 		const { write } = context;
 		write(this._typePrefix);
 		write(this._category);
+		write(this._context);
 		write(this.referencedExports);
 		super.serialize(context);
 	}
@@ -64,6 +92,7 @@ class ContextElementDependency extends ModuleDependency {
 		const { read } = context;
 		this._typePrefix = read();
 		this._category = read();
+		this._context = read();
 		this.referencedExports = read();
 		super.deserialize(context);
 	}

test/ContextModuleFactory.unittest.js

@@ -148,9 +148,10 @@ describe("ContextModuleFactory", () => {
 					expect(res).not.toStrictEqual([]);
 					expect(Array.isArray(res)).toBe(true);
 					expect(res.map(r => r.request)).toEqual([
-						"/a/B/a?query#hash",
-						"/b/A/b?query#hash"
+						"./B/a?query#hash",
+						"./A/b?query#hash"
 					]);
+					expect(res.map(r => r.getContext())).toEqual(["/a", "/b"]);
 					expect(res.map(r => r.userRequest)).toEqual(["./B/a", "./A/b"]);
 					done();
 				}

types.d.ts

@@ -2462,7 +2462,7 @@ declare interface ContainerReferencePluginOptions {
 	shareScope?: string;
 }
 declare abstract class ContextElementDependency extends ModuleDependency {
-	referencedExports: any;
+	referencedExports?: string[][];
 }
 declare class ContextExclusionPlugin {
 	constructor(negativeMatcher: RegExp);
@@ -2645,6 +2645,7 @@ declare class Dependency {
 		endLine?: any,
 		endColumn?: any
 	): void;
+	getContext(): undefined | string;
 	getResourceIdentifier(): null | string;
 	couldAffectReferencingModule(): boolean | typeof TRANSITIVE;