perf: improve FlagDependencyExportsPlugin for large JSON by depth

lib/WebpackOptionsApply.js

@@ -78,6 +78,8 @@ class WebpackOptionsApply extends OptionsApply {
 		compiler.recordsOutputPath = options.recordsOutputPath || null;
 		compiler.name = options.name;
 
+		const development = options.mode === "development";
+
 		if (options.externals) {
 			// @ts-expect-error https://github.com/microsoft/TypeScript/issues/41697
 			const ExternalsPlugin = require("./ExternalsPlugin");
@@ -290,7 +292,9 @@ class WebpackOptionsApply extends OptionsApply {
 		}
 
 		new JavascriptModulesPlugin().apply(compiler);
-		new JsonModulesPlugin().apply(compiler);
+		new JsonModulesPlugin({
+			depth: development ? 1 : Infinity
+		}).apply(compiler);
 		new AssetModulesPlugin().apply(compiler);
 
 		if (!options.experiments.outputModule) {

lib/dependencies/JsonExportsDependency.js

@@ -19,41 +19,47 @@ const NullDependency = require("./NullDependency");
 /** @typedef {import("../serialization/ObjectMiddleware").ObjectSerializerContext} ObjectSerializerContext */
 /** @typedef {import("../util/Hash")} Hash */
 
+/** @typedef {{depth:number}} JsonDependencyOptions */
+
 /**
- * @param {RawJsonData} data data
- * @returns {TODO} value
+ * @param {number} depth depth
+ * @returns {((data: RawJsonData, curDepth?: number) => ExportSpec[] | undefined)} value
  */
-const getExportsFromData = data => {
-	if (data && typeof data === "object") {
-		if (Array.isArray(data)) {
-			return data.length < 100
-				? data.map((item, idx) => ({
-						name: `${idx}`,
-						canMangle: true,
-						exports: getExportsFromData(item)
-					}))
-				: undefined;
+const getExportsWithDepth = depth =>
+	function getExportsFromData(data, curDepth = 1) {
+		if (curDepth > depth) return undefined;
+		if (data && typeof data === "object") {
+			if (Array.isArray(data)) {
+				return data.length < 100
+					? data.map((item, idx) => ({
+							name: `${idx}`,
+							canMangle: true,
+							exports: getExportsFromData(item, curDepth + 1)
+						}))
+					: undefined;
+			}
+			const exports = [];
+			for (const key of Object.keys(data)) {
+				exports.push({
+					name: key,
+					canMangle: true,
+					exports: getExportsFromData(data[key], curDepth + 1)
+				});
+			}
+			return exports;
 		}
-		const exports = [];
-		for (const key of Object.keys(data)) {
-			exports.push({
-				name: key,
-				canMangle: true,
-				exports: getExportsFromData(data[key])
-			});
-		}
-		return exports;
-	}
-	return undefined;
-};
+		return undefined;
+	};
 
 class JsonExportsDependency extends NullDependency {
 	/**
 	 * @param {JsonData} data json data
+	 * @param {JsonDependencyOptions} dependencyOptions dependency options
 	 */
-	constructor(data) {
+	constructor(data, dependencyOptions) {
 		super();
 		this.data = data;
+		this.options = dependencyOptions;
 	}
 
 	get type() {
@@ -67,7 +73,7 @@ class JsonExportsDependency extends NullDependency {
 	 */
 	getExports(moduleGraph) {
 		return {
-			exports: getExportsFromData(
+			exports: getExportsWithDepth(this.options.depth)(
 				this.data && /** @type {RawJsonData} */ (this.data.get())
 			),
 			dependencies: undefined

lib/json/JsonModulesPlugin.js

@@ -11,6 +11,7 @@ const JsonGenerator = require("./JsonGenerator");
 const JsonParser = require("./JsonParser");
 
 /** @typedef {import("../Compiler")} Compiler */
+/** @typedef {import("../dependencies/JsonExportsDependency").JsonDependencyOptions} JsonDependencyOptions */
 /** @typedef {Record<string, any>} RawJsonData */
 
 const validate = createSchemaValidation(
@@ -29,6 +30,13 @@ const PLUGIN_NAME = "JsonModulesPlugin";
  * It adds the json module type to the compiler and registers the json parser and generator.
  */
 class JsonModulesPlugin {
+	/**
+	 * @param {JsonDependencyOptions} dependencyOptions  dependency options
+	 */
+	constructor(dependencyOptions) {
+		this.dependencyOptions = dependencyOptions;
+	}
+
 	/**
 	 * Apply the plugin
 	 * @param {Compiler} compiler the compiler instance
@@ -43,7 +51,7 @@ class JsonModulesPlugin {
 					.tap(PLUGIN_NAME, parserOptions => {
 						validate(parserOptions);
 
-						return new JsonParser(parserOptions);
+						return new JsonParser(parserOptions, this.dependencyOptions);
 					});
 				normalModuleFactory.hooks.createGenerator
 					.for(JSON_MODULE_TYPE)

lib/json/JsonParser.js

@@ -15,17 +15,20 @@ const JsonData = require("./JsonData");
 /** @typedef {import("../Module").BuildMeta} BuildMeta */
 /** @typedef {import("../Parser").ParserState} ParserState */
 /** @typedef {import("../Parser").PreparsedAst} PreparsedAst */
+/** @typedef {import("../dependencies/JsonExportsDependency").JsonDependencyOptions} JsonDependencyOptions */
 /** @typedef {import("./JsonModulesPlugin").RawJsonData} RawJsonData */
 
 const getParseJson = memoize(() => require("json-parse-even-better-errors"));
 
 class JsonParser extends Parser {
 	/**
-	 * @param {JsonModulesPluginParserOptions} options parser options
+	 * @param {JsonModulesPluginParserOptions} parserOptions parser options
+	 * @param {JsonDependencyOptions} dependencyOptions dependency options
 	 */
-	constructor(options) {
+	constructor(parserOptions, dependencyOptions) {
 		super();
-		this.options = options || {};
+		this.options = parserOptions || {};
+		this.dependencyOptions = dependencyOptions;
 	}
 
 	/**
@@ -63,7 +66,9 @@ class JsonParser extends Parser {
 		buildMeta.exportsType = "default";
 		buildMeta.defaultObject =
 			typeof data === "object" ? "redirect-warn" : false;
-		state.module.addDependency(new JsonExportsDependency(jsonData));
+		state.module.addDependency(
+			new JsonExportsDependency(jsonData, this.dependencyOptions)
+		);
 		return state;
 	}
 }

test/configCases/json/flag-dep-export-perf/data.json

@@ -0,0 +1,27 @@
+{
+  "depth_1": {
+    "depth_2": {
+      "depth_3": {
+        "depth_4": {
+          "depth_5": {
+            "depth_6": "depth_6"
+          }
+        }
+      }
+    }
+  },
+  "_depth_1": {
+    "_depth_2": {
+      "_depth_3": {
+        "_depth_4": {
+          "_depth_5": {
+            "_depth_6": "_depth_6"
+          }
+        }
+      }
+    }
+  },
+  "__depth_1": [
+    { "__depth_3": [{ "__depth_5": [{ "__depth_7": ["__depth_8"] }] }] }
+  ]
+}

test/configCases/json/flag-dep-export-perf/index.js

@@ -0,0 +1,11 @@
+export * from './data.json';
+
+it("should compile and run", () => {
+	expect(__webpack_exports_info__.depth_1.provideInfo).toBe(true)
+	expect(__webpack_exports_info__._depth_1.provideInfo).toBe(true)
+	expect(__webpack_exports_info__.__depth_1.provideInfo).toBe(true)
+
+	expect(__webpack_exports_info__.depth_1.depth_2.provideInfo).toBe(undefined)
+	expect(__webpack_exports_info__._depth_1._depth_2._depth_3._depth_4.provideInfo).toBe(undefined)
+	expect(__webpack_exports_info__.__depth_1[0].__depth_3[0].__depth_5.provideInfo).toBe(undefined)
+});

test/configCases/json/flag-dep-export-perf/webpack.config.js

@@ -0,0 +1,4 @@
+/** @type {import("../../../../").Configuration} */
+module.exports = {
+	mode: "development"
+};