Merge pull request #15801 from webpack/refactor-json-modules

refactor json modules

lib/dependencies/JsonExportsDependency.js

@@ -13,18 +13,21 @@ const NullDependency = require("./NullDependency");
 /** @typedef {import("../Dependency").ExportsSpec} ExportsSpec */
 /** @typedef {import("../Dependency").UpdateHashContext} UpdateHashContext */
 /** @typedef {import("../ModuleGraph")} ModuleGraph */
+/** @typedef {import("../json/JsonData")} JsonData */
 /** @typedef {import("../util/Hash")} Hash */
 
 const getExportsFromData = data => {
 	if (data && typeof data === "object") {
 		if (Array.isArray(data)) {
-			return data.map((item, idx) => {
-				return {
-					name: `${idx}`,
-					canMangle: true,
-					exports: getExportsFromData(item)
-				};
-			});
+			return data.length < 100
+				? data.map((item, idx) => {
+						return {
+							name: `${idx}`,
+							canMangle: true,
+							exports: getExportsFromData(item)
+						};
+				  })
+				: undefined;
 		} else {
 			const exports = [];
 			for (const key of Object.keys(data)) {
@@ -42,12 +45,11 @@ const getExportsFromData = data => {
 
 class JsonExportsDependency extends NullDependency {
 	/**
-	 * @param {(string | ExportSpec)[]} exports json exports
+	 * @param {JsonData=} data json data
 	 */
-	constructor(exports) {
+	constructor(data) {
 		super();
-		this.exports = exports;
-		this._hashUpdate = undefined;
+		this.data = data;
 	}
 
 	get type() {
@@ -61,7 +63,7 @@ class JsonExportsDependency extends NullDependency {
 	 */
 	getExports(moduleGraph) {
 		return {
-			exports: this.exports,
+			exports: getExportsFromData(this.data && this.data.get()),
 			dependencies: undefined
 		};
 	}
@@ -73,23 +75,18 @@ class JsonExportsDependency extends NullDependency {
 	 * @returns {void}
 	 */
 	updateHash(hash, context) {
-		if (this._hashUpdate === undefined) {
-			this._hashUpdate = this.exports
-				? JSON.stringify(this.exports)
-				: "undefined";
-		}
-		hash.update(this._hashUpdate);
+		this.data.updateHash(hash);
 	}
 
 	serialize(context) {
 		const { write } = context;
-		write(this.exports);
+		write(this.data);
 		super.serialize(context);
 	}
 
 	deserialize(context) {
 		const { read } = context;
-		this.exports = read();
+		this.data = read();
 		super.deserialize(context);
 	}
 }
@@ -100,4 +97,3 @@ makeSerializable(
 );
 
 module.exports = JsonExportsDependency;
-module.exports.getExportsFromData = getExportsFromData;

lib/json/JsonData.js

@@ -24,6 +24,14 @@ class JsonData {
 		}
 		return this._data;
 	}
+
+	updateHash(hash) {
+		if (this._buffer === undefined && this._data !== undefined) {
+			this._buffer = Buffer.from(JSON.stringify(this._data));
+		}
+
+		if (this._buffer) return hash.update(this._buffer);
+	}
 }
 
 register(JsonData, "webpack/lib/json/JsonData", null, {

lib/json/JsonParser.js

@@ -41,15 +41,13 @@ class JsonParser extends Parser {
 			typeof source === "object"
 				? source
 				: parseFn(source[0] === "\ufeff" ? source.slice(1) : source);
-
-		state.module.buildInfo.jsonData = new JsonData(data);
+		const jsonData = new JsonData(data);
+		state.module.buildInfo.jsonData = jsonData;
 		state.module.buildInfo.strict = true;
 		state.module.buildMeta.exportsType = "default";
 		state.module.buildMeta.defaultObject =
 			typeof data === "object" ? "redirect-warn" : false;
-		state.module.addDependency(
-			new JsonExportsDependency(JsonExportsDependency.getExportsFromData(data))
-		);
+		state.module.addDependency(new JsonExportsDependency(jsonData));
 		return state;
 	}
 }

test/MemoryLimitTestCases.test.js

@@ -0,0 +1,131 @@
+"use strict";
+
+require("./helpers/warmup-webpack");
+const path = require("path");
+const fs = require("graceful-fs");
+const rimraf = require("rimraf");
+const captureStdio = require("./helpers/captureStdio");
+const webpack = require("..");
+
+const toMiB = bytes => `${Math.round(bytes / 1024 / 1024)}MiB`;
+const base = path.join(__dirname, "memoryLimitCases");
+const outputBase = path.join(__dirname, "js", "memoryLimit");
+const tests = fs
+	.readdirSync(base)
+	.filter(
+		testName =>
+			fs.existsSync(path.join(base, testName, "index.js")) ||
+			fs.existsSync(path.join(base, testName, "webpack.config.js"))
+	)
+	.filter(testName => {
+		const testDirectory = path.join(base, testName);
+		const filterPath = path.join(testDirectory, "test.filter.js");
+		if (fs.existsSync(filterPath) && !require(filterPath)()) {
+			describe.skip(testName, () => it("filtered"));
+			return false;
+		}
+		return true;
+	});
+
+describe("MemoryLimitTestCases", () => {
+	jest.setTimeout(40000);
+	let stderr;
+	beforeEach(() => {
+		stderr = captureStdio(process.stderr, true);
+		if (global.gc) {
+			global.gc();
+			global.gc();
+		}
+	});
+	afterEach(() => {
+		stderr.restore();
+	});
+	tests.forEach(testName => {
+		let testConfig = {
+			heapSizeLimitBytes: 250 * 1024 * 1024
+		};
+		try {
+			// try to load a test file
+			testConfig = Object.assign(
+				testConfig,
+				require(path.join(base, testName, "test.config.js"))
+			);
+		} catch (e) {
+			// ignored
+		}
+		it(`should build ${JSON.stringify(testName)} with heap limit of ${toMiB(
+			testConfig.heapSizeLimitBytes
+		)}`, done => {
+			const outputDirectory = path.join(outputBase, testName);
+			rimraf.sync(outputDirectory);
+			fs.mkdirSync(outputDirectory, { recursive: true });
+			let options = {
+				mode: "development",
+				entry: "./index",
+				output: {
+					filename: "bundle.js"
+				}
+			};
+			if (fs.existsSync(path.join(base, testName, "webpack.config.js"))) {
+				options = require(path.join(base, testName, "webpack.config.js"));
+			}
+
+			(Array.isArray(options) ? options : [options]).forEach(options => {
+				if (!options.context) options.context = path.join(base, testName);
+				if (!options.output) options.output = options.output || {};
+				if (!options.output.path) options.output.path = outputDirectory;
+				if (!options.plugins) options.plugins = [];
+				if (!options.optimization) options.optimization = {};
+				if (options.optimization.minimize === undefined)
+					options.optimization.minimize = false;
+			});
+			const heapSizeStart = process.memoryUsage().heapUsed;
+			const c = webpack(options);
+			const compilers = c.compilers ? c.compilers : [c];
+			compilers.forEach(c => {
+				const ifs = c.inputFileSystem;
+				c.inputFileSystem = Object.create(ifs);
+				c.inputFileSystem.readFile = function () {
+					const args = Array.prototype.slice.call(arguments);
+					const callback = args.pop();
+					ifs.readFile.apply(
+						ifs,
+						args.concat([
+							(err, result) => {
+								if (err) return callback(err);
+								if (!/\.(js|json|txt)$/.test(args[0]))
+									return callback(null, result);
+								callback(null, result.toString("utf-8").replace(/\r/g, ""));
+							}
+						])
+					);
+				};
+			});
+			c.run((err, stats) => {
+				if (err) return done(err);
+				if (/error$/.test(testName)) {
+					expect(stats.hasErrors()).toBe(true);
+				} else if (stats.hasErrors()) {
+					return done(
+						new Error(
+							stats.toString({
+								all: false,
+								errors: true,
+								errorStack: true,
+								errorDetails: true
+							})
+						)
+					);
+				}
+				const heapUsed = process.memoryUsage().heapUsed - heapSizeStart;
+				if (heapUsed > testConfig.heapSizeLimitBytes) {
+					return done(
+						new Error(`Out of memory limit with ${toMiB(heapUsed)} heap used`)
+					);
+				}
+				if (testConfig.validate) testConfig.validate(stats, stderr.toString());
+				done();
+			});
+		});
+	});
+});

test/memoryLimitCases/json/index.js

@@ -0,0 +1 @@
+const ctx = require.context("./src", false, /\.json$/);

test/memoryLimitCases/json/src/1.json

@@ -0,0 +1 @@
+{"type":"Topology","box":[-73.9958013,45.3984821,-73.4742952,45.7047897],"transform":{"scale":[0.0005225512024048059,0.00030692144288576825],"translate":[-73.9958013,45.3984821]},"objects":{"boundary":{"type":"Polygon","arcs":[[0]],"id":"relation/8508277","properties":{"admin_level":"6","alt_name:1":"Montréal","boundary":"administrative","name":"Agglomération de Montréal","name:en":"Urban agglomeration of Montreal","name:fr":"Agglomération de Montréal","type":"boundary","wikidata":"Q2826806","wikipedia":"fr:Agglomération de Montréal","id":"relation/8508277"}}},"arcs":[[[992,804],[-2,23],[-15,31],[-3,32],[4,45],[12,24],[2,14],[5,9],[3,8],[-4,7],[-23,-3],[-4,4],[-8,-1],[-5,-2],[-22,-7],[-18,-7],[-10,-1],[-8,-25],[-5,-18],[-6,-11],[-11,-9],[-18,-14],[-29,-31],[-25,-20],[-6,-5],[-53,-44],[-17,-21],[-14,-17],[-17,-22],[-3,-9],[-6,-16],[-5,-24],[-2,-6],[-6,-22],[-13,-25],[-11,-21],[-5,-11],[-2,-3],[-12,-28],[-1,-3],[-1,-25],[-11,-22],[-2,-3],[-1,-4],[-3,-8],[0,-2],[-4,-6],[-6,-6],[-23,-7],[-7,-3],[-6,-3],[-14,-11],[-6,-11],[-11,-7],[-7,-3],[-3,-1],[-16,-17],[-11,-8],[-8,-5],[-3,-5],[-9,-22],[-11,-3],[-11,-8],[-5,-10],[-5,-5],[-4,-1],[-10,-3],[-27,3],[-20,4],[-11,9],[-8,0],[-10,7],[-15,-5],[-5,0],[-21,8],[-20,0],[-2,-2],[-3,-1],[-3,-4],[-7,-12],[-3,-3],[-1,-1],[-2,-1],[-2,1],[-6,12],[-8,4],[-3,5],[-1,5],[-7,1],[-14,1],[-7,0],[-8,3],[-11,6],[-7,5],[-7,6],[-11,-4],[-11,-9],[-6,-7],[-7,-12],[-8,-11],[-7,-9],[-21,-21],[-19,-13],[-14,-19],[-10,-19],[-5,-16],[-7,-13],[-11,-26],[-14,-17],[-15,-20],[-10,-6],[-12,-4],[-4,0],[5,-17],[0,-3],[1,-2],[1,-6],[3,-10],[2,-12],[2,-9],[2,-9],[2,-5],[2,-19],[0,-25],[10,-13],[17,-16],[14,-14],[5,-6],[6,-7],[2,-2],[1,0],[1,-1],[1,0],[11,-5],[6,-3],[2,-1],[6,0],[16,1],[21,2],[12,5],[13,3],[3,2],[6,3],[2,2],[8,7],[12,5],[5,2],[3,0],[4,0],[6,-2],[18,-9],[13,-5],[25,-6],[36,-6],[29,-3],[9,-2],[22,-5],[7,11],[4,7],[5,7],[5,4],[1,1],[3,4],[7,5],[7,5],[8,4],[9,6],[8,5],[12,8],[49,5],[14,1],[5,1],[13,2],[45,1],[12,1],[12,0],[4,0],[8,-1],[11,-2],[8,-3],[9,-3],[12,-5],[3,-2],[6,-3],[18,-10],[10,-6],[9,-3],[5,-1],[1,0],[7,-1],[2,0],[12,1],[13,1],[16,1],[6,1],[7,1],[36,4],[24,4],[15,4],[20,7],[13,8],[7,5],[4,3],[14,14],[9,15],[7,21],[2,7],[3,26],[1,14],[-1,23],[0,5],[0,5],[0,21],[-2,7],[-2,7],[-5,16],[-2,23],[-1,6],[-4,10],[7,5],[2,1],[1,3],[1,1],[2,2],[3,4],[-1,5],[2,2],[-2,10],[-3,16],[-8,45],[-2,7],[0,3],[-2,9],[0,3],[-4,29],[-2,10],[19,25],[14,32],[10,25],[14,35],[1,4],[0,17],[3,18],[-4,33],[-2,25],[3,20],[4,12],[17,40],[9,21],[4,11],[10,33]]]}