Merge pull request #15413 from cool-little-fish/fix-15274

fix: use relative path in source map for context module

lib/Compilation.js

@@ -3328,7 +3328,8 @@ Or do you want to use the entrypoints '${name}' and '${runtime}' independently o
 						dependencyTemplates,
 						runtimeTemplate,
 						runtime,
-						codeGenerationResults: results
+						codeGenerationResults: results,
+						compilation: this
 					});
 				} catch (err) {
 					errors.push(new CodeGenerationError(module, err));

lib/ContextModule.js

@@ -19,7 +19,11 @@ const {
 	keepOriginalOrder,
 	compareModulesById
 } = require("./util/comparators");
-const { contextify, parseResource } = require("./util/identifier");
+const {
+	contextify,
+	parseResource,
+	makePathsRelative
+} = require("./util/identifier");
 const makeSerializable = require("./util/makeSerializable");
 
 /** @typedef {import("webpack-sources").Source} Source */
@@ -1066,9 +1070,21 @@ module.exports = webpackEmptyAsyncContext;`;
 		return this.getSourceForEmptyContext(id, runtimeTemplate);
 	}
 
-	getSource(sourceString) {
+	/**
+	 * @param {string} sourceString source content
+	 * @param {Compilation=} compilation the compilation
+	 * @returns {Source} generated source
+	 */
+	getSource(sourceString, compilation) {
 		if (this.useSourceMap || this.useSimpleSourceMap) {
-			return new OriginalSource(sourceString, this.identifier());
+			return new OriginalSource(
+				sourceString,
+				`webpack://${makePathsRelative(
+					(compilation && compilation.compiler.context) || "",
+					this.identifier(),
+					compilation && compilation.compiler.root
+				)}`
+			);
 		}
 		return new RawSource(sourceString);
 	}
@@ -1078,11 +1094,14 @@ module.exports = webpackEmptyAsyncContext;`;
 	 * @returns {CodeGenerationResult} result
 	 */
 	codeGeneration(context) {
-		const { chunkGraph } = context;
+		const { chunkGraph, compilation } = context;
 		const sources = new Map();
 		sources.set(
 			"javascript",
-			this.getSource(this.getSourceString(this.options.mode, context))
+			this.getSource(
+				this.getSourceString(this.options.mode, context),
+				compilation
+			)
 		);
 		const set = new Set();
 		const allDeps = /** @type {ContextElementDependency[]} */ (

lib/Module.js

@@ -49,6 +49,7 @@ const makeSerializable = require("./util/makeSerializable");
  * @property {string=} type the type of source that should be generated
  */
 
+// TODO webpack 6: compilation will be required in CodeGenerationContext
 /**
  * @typedef {Object} CodeGenerationContext
  * @property {DependencyTemplates} dependencyTemplates the dependency templates
@@ -58,6 +59,7 @@ const makeSerializable = require("./util/makeSerializable");
  * @property {RuntimeSpec} runtime the runtimes code should be generated for
  * @property {ConcatenationScope=} concatenationScope when in concatenated module, information about other concatenated modules
  * @property {CodeGenerationResults} codeGenerationResults code generation results of other modules (need to have a codeGenerationDependency to use that)
+ * @property {Compilation=} compilation the compilation
  */
 
 /**

test/__snapshots__/StatsTestCases.basictest.js.snap

@@ -738,7 +738,7 @@ exports[`StatsTestCases should print correct stats for concat-and-sideeffects 1`
 
 exports[`StatsTestCases should print correct stats for context-independence 1`] = `
 "asset main-1aad2f42f93e93c4e0b4.js 12.7 KiB [emitted] [immutable] (name: main)
-  sourceMap main-1aad2f42f93e93c4e0b4.js.map 11.1 KiB [emitted] [dev] (auxiliary name: main)
+  sourceMap main-1aad2f42f93e93c4e0b4.js.map 11 KiB [emitted] [dev] (auxiliary name: main)
 asset 695-4dd37417c69a0af66bac.js 455 bytes [emitted] [immutable]
   sourceMap 695-4dd37417c69a0af66bac.js.map 342 bytes [emitted] [dev]
 runtime modules 6.6 KiB 9 modules
@@ -754,7 +754,7 @@ built modules 500 bytes [built]
 webpack x.x.x compiled successfully in X ms
 
 asset main-1aad2f42f93e93c4e0b4.js 12.7 KiB [emitted] [immutable] (name: main)
-  sourceMap main-1aad2f42f93e93c4e0b4.js.map 11.1 KiB [emitted] [dev] (auxiliary name: main)
+  sourceMap main-1aad2f42f93e93c4e0b4.js.map 11 KiB [emitted] [dev] (auxiliary name: main)
 asset 695-4dd37417c69a0af66bac.js 455 bytes [emitted] [immutable]
   sourceMap 695-4dd37417c69a0af66bac.js.map 342 bytes [emitted] [dev]
 runtime modules 6.6 KiB 9 modules

test/configCases/source-map/context-module-source-path/foo/a.js

@@ -0,0 +1 @@
+module.exports = "a";

test/configCases/source-map/context-module-source-path/foo/b.js

@@ -0,0 +1 @@
+module.exports = "b";

test/configCases/source-map/context-module-source-path/index.js

@@ -0,0 +1,9 @@
+const foo = Math.random() > 0.5 ? "a" : "b";
+require(`./foo/${foo}.js`);
+
+it("context module should use relative path in source map file", () => {
+	var fs = require("fs");
+	var source = fs.readFileSync(__filename + ".map", "utf-8");
+	var map = JSON.parse(source);
+	expect(map.sources).toContain("webpack:///./foo/ sync ^\\.\\/.*\\.js$");
+});

test/configCases/source-map/context-module-source-path/webpack.config.js

@@ -0,0 +1,7 @@
+module.exports = {
+	node: {
+		__dirname: false,
+		__filename: false
+	},
+	devtool: "source-map"
+};

types.d.ts

@@ -1239,6 +1239,11 @@ declare interface CodeGenerationContext {
 	 * code generation results of other modules (need to have a codeGenerationDependency to use that)
 	 */
 	codeGenerationResults: CodeGenerationResults;
+
+	/**
+	 * the compilation
+	 */
+	compilation?: Compilation;
 }
 declare interface CodeGenerationResult {
 	/**