replace Object.assign with object spread

lib/Compilation.js

@@ -567,7 +567,7 @@ class Compilation {
 			optionsOrPreset = { preset: optionsOrPreset };
 		}
 		if (typeof optionsOrPreset === "object" && optionsOrPreset !== null) {
-			const options = Object.assign({}, optionsOrPreset);
+			const options = { ...optionsOrPreset };
 			if (options.preset !== undefined) {
 				this.hooks.statsPreset.for(options.preset).call(options, context);
 			}
@@ -2528,12 +2528,10 @@ class Compilation {
 	 */
 	getPath(filename, data) {
 		if (!data.hash) {
-			data = Object.assign(
-				{
-					hash: this.hash
-				},
-				data
-			);
+			data = {
+				hash: this.hash,
+				...data
+			};
 		}
 		return this.mainTemplate.getAssetPath(filename, data);
 	}

lib/ContextModule.js

@@ -93,7 +93,8 @@ class ContextModule extends Module {
 		// Info from Factory
 		this.resolveDependencies = resolveDependencies;
 		/** @type {ContextModuleOptions} */
-		this.options = Object.assign({}, options, {
+		this.options = ({
+			...options,
 			resource: resource,
 			resourceQuery: resourceQuery
 		});
@@ -324,11 +325,10 @@ class ContextModule extends Module {
 				// for the lazy-once mode create a new async dependency block
 				// and add that block to this context
 				if (dependencies.length > 0) {
-					const block = new AsyncDependenciesBlock(
-						Object.assign({}, this.options.groupOptions, {
-							name: this.options.chunkName
-						})
-					);
+					const block = new AsyncDependenciesBlock({
+						...this.options.groupOptions,
+						name: this.options.chunkName
+					});
 					for (const dep of dependencies) {
 						block.addDependency(dep);
 					}
@@ -360,9 +360,10 @@ class ContextModule extends Module {
 						);
 					}
 					const block = new AsyncDependenciesBlock(
-						Object.assign({}, this.options.groupOptions, {
+						{
+							...this.options.groupOptions,
 							name: chunkName
-						}),
+						},
 						dep.loc,
 						dep.userRequest
 					);

lib/ContextModuleFactory.js

@@ -49,17 +49,15 @@ module.exports = class ContextModuleFactory extends ModuleFactory {
 		const missingDependencies = new Set();
 		const contextDependencies = new Set();
 		this.hooks.beforeResolve.callAsync(
-			Object.assign(
-				{
-					context: context,
-					dependencies: dependencies,
-					resolveOptions,
-					fileDependencies,
-					missingDependencies,
-					contextDependencies
-				},
-				dependency.options
-			),
+			{
+				context: context,
+				dependencies: dependencies,
+				resolveOptions,
+				fileDependencies,
+				missingDependencies,
+				contextDependencies,
+				...dependency.options
+			},
 			(err, beforeResolveResult) => {
 				if (err) return callback(err);
 
@@ -145,17 +143,15 @@ module.exports = class ContextModuleFactory extends ModuleFactory {
 						if (err) return callback(err);
 
 						this.hooks.afterResolve.callAsync(
-							Object.assign(
-								{
-									addon:
-										loadersPrefix +
-										result[1].join("!") +
-										(result[1].length > 0 ? "!" : ""),
-									resource: result[0],
-									resolveDependencies: this.resolveDependencies.bind(this)
-								},
-								beforeResolveResult
-							),
+							{
+								addon:
+									loadersPrefix +
+									result[1].join("!") +
+									(result[1].length > 0 ? "!" : ""),
+								resource: result[0],
+								resolveDependencies: this.resolveDependencies.bind(this),
+								...beforeResolveResult
+							},
 							(err, result) => {
 								if (err) return callback(err);
 

lib/DelegatedModule.js

@@ -87,7 +87,7 @@ class DelegatedModule extends Module {
 	 * @returns {void}
 	 */
 	build(options, compilation, resolver, fs, callback) {
-		this.buildMeta = Object.assign({}, this.delegateData.buildMeta);
+		this.buildMeta = { ...this.delegateData.buildMeta };
 		this.buildInfo = {};
 		this.dependencies.length = 0;
 		this.delegatedSourceDependency = new DelegatedSourceDependency(

lib/DelegatedPlugin.js

@@ -38,14 +38,10 @@ class DelegatedPlugin {
 		);
 
 		compiler.hooks.compile.tap("DelegatedPlugin", ({ normalModuleFactory }) => {
-			new DelegatedModuleFactoryPlugin(
-				Object.assign(
-					{
-						associatedObjectForCache: compiler.root
-					},
-					this.options
-				)
-			).apply(normalModuleFactory);
+			new DelegatedModuleFactoryPlugin({
+				associatedObjectForCache: compiler.root,
+				...this.options
+			}).apply(normalModuleFactory);
 		});
 	}
 }

lib/JavascriptParser.js

@@ -2409,11 +2409,10 @@ class JavascriptParser {
 
 	static parse(code, options) {
 		const type = options ? options.sourceType : "module";
-		const parserOptions = Object.assign(
-			Object.create(null),
-			defaultParserOptions,
-			options
-		);
+		const parserOptions = {
+			...defaultParserOptions,
+			...options
+		};
 
 		if (type === "auto") {
 			parserOptions.sourceType = "module";

lib/ModuleFilenameHelpers.js

@@ -60,17 +60,15 @@ ModuleFilenameHelpers.createFilename = (
 	options,
 	{ requestShortener, chunkGraph }
 ) => {
-	const opts = Object.assign(
-		{
-			namespace: "",
-			moduleFilenameTemplate: ""
-		},
-		typeof options === "object"
+	const opts = {
+		namespace: "",
+		moduleFilenameTemplate: "",
+		...(typeof options === "object"
 			? options
 			: {
 					moduleFilenameTemplate: options
-			  }
-	);
+			  })
+	};
 
 	let absoluteResourcePath;
 	let hash;

lib/MultiStats.js

@@ -47,13 +47,12 @@ class MultiStats {
 				? options.children[idx]
 				: options.children;
 			return stat.compilation.createStatsOptions(
-				Object.assign(
-					{},
-					baseOptions,
-					childOptions && typeof childOptions === "object"
+				{
+					...baseOptions,
+					...(childOptions && typeof childOptions === "object"
 						? childOptions
-						: { preset: childOptions }
-				),
+						: { preset: childOptions })
+				},
 				context
 			);
 		});
@@ -101,11 +100,12 @@ class MultiStats {
 			if (!j.errors) return arr;
 			return arr.concat(
 				j.errors.map(obj => {
-					return Object.assign({}, obj, {
+					return {
+						...obj,
 						compilerPath: obj.compilerPath
 							? `${j.name}.${obj.compilerPath}`
 							: j.name
-					});
+					};
 				})
 			);
 		}, []);
@@ -113,11 +113,12 @@ class MultiStats {
 			if (!j.warnings) return arr;
 			return arr.concat(
 				j.warnings.map(obj => {
-					return Object.assign({}, obj, {
+					return {
+						...obj,
 						compilerPath: obj.compilerPath
 							? `${j.name}.${obj.compilerPath}`
 							: j.name
-					});
+					};
 				})
 			);
 		}, []);

lib/NodeStuffPlugin.js

@@ -38,7 +38,7 @@ class NodeStuffPlugin {
 
 					let localOptions = options;
 					if (parserOptions.node) {
-						localOptions = Object.assign({}, localOptions, parserOptions.node);
+						localOptions = { ...localOptions, ...parserOptions.node };
 					}
 
 					const setModuleConstant = (expressionName, fn) => {

lib/NormalModule.js

@@ -468,7 +468,7 @@ class NormalModule extends Module {
 	 */
 	markModuleAsErrored(error) {
 		// Restore build meta from successful build to keep importing state
-		this.buildMeta = Object.assign({}, this._lastSuccessfulBuildMeta);
+		this.buildMeta = { ...this._lastSuccessfulBuildMeta };
 		this.error = error;
 		this.errors.push(error);
 	}

lib/OptionsDefaulter.js

@@ -32,7 +32,7 @@ class OptionsDefaulter {
 	}
 
 	process(options) {
-		options = Object.assign({}, options);
+		options = { ...options };
 		for (let name in this.defaults) {
 			switch (this.config[name]) {
 				case undefined:

lib/ProgressPlugin.js

@@ -110,7 +110,7 @@ class ProgressPlugin {
 
 		options = options || {};
 		validateOptions(schema, options, "Progress Plugin");
-		options = Object.assign({}, ProgressPlugin.defaultOptions, options);
+		options = { ...ProgressPlugin.defaultOptions, ...options };
 
 		this.profile = options.profile;
 		this.handler = options.handler;

lib/ResolverFactory.js

@@ -67,7 +67,7 @@ module.exports = class ResolverFactory {
 	 * @returns {Resolver} the resolver
 	 */
 	_create(type, resolveOptions) {
-		const originalResolveOptions = Object.assign({}, resolveOptions);
+		const originalResolveOptions = { ...resolveOptions };
 		resolveOptions = this.hooks.resolveOptions.for(type).call(resolveOptions);
 		const resolver = Factory.createResolver(resolveOptions);
 		if (!resolver) {

lib/Watching.js

@@ -37,7 +37,7 @@ class Watching {
 				aggregateTimeout: watchOptions
 			};
 		} else if (watchOptions && typeof watchOptions === "object") {
-			this.watchOptions = Object.assign({}, watchOptions);
+			this.watchOptions = { ...watchOptions };
 		} else {
 			this.watchOptions = {};
 		}

lib/WebpackOptionsApply.js

@@ -617,33 +617,27 @@ class WebpackOptionsApply extends OptionsApply {
 		compiler.resolverFactory.hooks.resolveOptions
 			.for("normal")
 			.tap("WebpackOptionsApply", resolveOptions => {
-				return Object.assign(
-					{
-						fileSystem: compiler.inputFileSystem
-					},
-					cachedCleverMerge(options.resolve, resolveOptions)
-				);
+				return {
+					fileSystem: compiler.inputFileSystem,
+					...cachedCleverMerge(options.resolve, resolveOptions)
+				};
 			});
 		compiler.resolverFactory.hooks.resolveOptions
 			.for("context")
 			.tap("WebpackOptionsApply", resolveOptions => {
-				return Object.assign(
-					{
-						fileSystem: compiler.inputFileSystem,
-						resolveToContext: true
-					},
-					cachedCleverMerge(options.resolve, resolveOptions)
-				);
+				return {
+					fileSystem: compiler.inputFileSystem,
+					resolveToContext: true,
+					...cachedCleverMerge(options.resolve, resolveOptions)
+				};
 			});
 		compiler.resolverFactory.hooks.resolveOptions
 			.for("loader")
 			.tap("WebpackOptionsApply", resolveOptions => {
-				return Object.assign(
-					{
-						fileSystem: compiler.inputFileSystem
-					},
-					cachedCleverMerge(options.resolveLoader, resolveOptions)
-				);
+				return {
+					fileSystem: compiler.inputFileSystem,
+					...cachedCleverMerge(options.resolveLoader, resolveOptions)
+				};
 			});
 		compiler.hooks.afterResolvers.call(compiler);
 		return options;

lib/WebpackOptionsDefaulter.js

@@ -35,7 +35,7 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
 	constructor() {
 		super();
 
-		this.set("experiments", "call", value => Object.assign({}, value));
+		this.set("experiments", "call", value => ({ ...value }));
 		this.set("experiments.mjs", false);
 		this.set("experiments.importAwait", false);
 		this.set("experiments.importAsync", false);
@@ -60,7 +60,7 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
 			if (!value) {
 				return false;
 			}
-			value = Object.assign({}, value);
+			value = { ...value };
 			if (value.type === "filesystem") {
 				if (value.name === undefined) {
 					value.name =
@@ -95,7 +95,7 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
 		this.set("context", process.cwd());
 		this.set("target", "web");
 
-		this.set("module", "call", value => Object.assign({}, value));
+		this.set("module", "call", value => ({ ...value }));
 		this.set("module.unknownContextRequest", ".");
 		this.set("module.unknownContextRegExp", false);
 		this.set("module.unknownContextRecursive", true);
@@ -159,7 +159,7 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
 			} else if (typeof value !== "object") {
 				return {};
 			} else {
-				return Object.assign({}, value);
+				return { ...value };
 			}
 		});
 
@@ -236,7 +236,7 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
 			if (typeof value === "boolean") {
 				return value;
 			} else {
-				return Object.assign({}, value);
+				return { ...value };
 			}
 		});
 		this.set("node.global", "make", options => {
@@ -277,7 +277,7 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
 				(!isProductionLikeMode(options) || !isWebLikeTarget(options))
 			)
 				return false;
-			return Object.assign({}, value);
+			return { ...value };
 		});
 		this.set("performance.maxAssetSize", 250000);
 		this.set("performance.maxEntrypointSize", 250000);
@@ -285,7 +285,7 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
 			isProductionLikeMode(options) ? "warning" : false
 		);
 
-		this.set("optimization", "call", value => Object.assign({}, value));
+		this.set("optimization", "call", value => ({ ...value }));
 		this.set("optimization.removeAvailableModules", true);
 		this.set("optimization.removeEmptyChunks", true);
 		this.set("optimization.mergeDuplicateChunks", true);
@@ -404,7 +404,7 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
 			}
 		});
 
-		this.set("resolve", "call", value => Object.assign({}, value));
+		this.set("resolve", "call", value => ({ ...value }));
 		this.set("resolve.cache", "make", options => !!options.cache);
 		this.set("resolve.modules", ["node_modules"]);
 		this.set("resolve.extensions", "make", options =>
@@ -436,7 +436,7 @@ class WebpackOptionsDefaulter extends OptionsDefaulter {
 			}
 		});
 
-		this.set("resolveLoader", "call", value => Object.assign({}, value));
+		this.set("resolveLoader", "call", value => ({ ...value }));
 		this.set("resolveLoader.cache", "make", options => !!options.cache);
 		this.set("resolveLoader.mainFields", ["loader", "main"]);
 		this.set("resolveLoader.extensions", [".js"]);

lib/WebpackOptionsValidationError.js

@@ -240,16 +240,11 @@ class WebpackOptionsValidationError extends WebpackError {
 						0,
 						err.children.length - 1
 					);
-					return WebpackOptionsValidationError.formatValidationError(
-						Object.assign({}, lastChild, {
-							children: remainingChildren,
-							parentSchema: Object.assign(
-								{},
-								err.parentSchema,
-								lastChild.parentSchema
-							)
-						})
-					);
+					return WebpackOptionsValidationError.formatValidationError({
+						...lastChild,
+						children: remainingChildren,
+						parentSchema: { ...err.parentSchema, ...lastChild.parentSchema }
+					});
 				}
 				const children = filterChildren(err.children);
 				if (children.length === 1) {

lib/cache/ResolverCachePlugin.js

@@ -42,18 +42,17 @@ class ResolverCachePlugin {
 			request,
 			callback
 		) => {
-			const newRequest = Object.assign(
-				{
-					_ResolverCachePluginCacheMiss: true
-				},
-				request
-			);
-			const newResolveContext = Object.assign({}, resolveContext, {
+			const newRequest = {
+				_ResolverCachePluginCacheMiss: true,
+				...request
+			};
+			const newResolveContext = {
+				...resolveContext,
 				stack: new Set(),
 				missing: new Set(),
 				fileDependencies: new Set(),
 				contextDependencies: new Set()
-			});
+			};
 			const propagate = key => {
 				if (resolveContext[key]) {
 					for (const dep of newResolveContext[key]) {

lib/dependencies/ContextDependency.js

@@ -35,7 +35,7 @@ class ContextDependency extends Dependency {
 			this.options &&
 			(this.options.regExp.global || this.options.regExp.sticky)
 		) {
-			this.options = Object.assign({}, this.options, { regExp: null });
+			this.options = { ...this.options, regExp: null };
 			this.hadGlobalOrStickyRegExp = true;
 		}
 

lib/dependencies/ContextDependencyHelpers.js

@@ -93,15 +93,13 @@ exports.create = (Dep, range, param, expr, options, contextOptions, parser) => {
 			`^${quotemeta(prefix)}${innerRegExp}${quotemeta(postfix)}$`
 		);
 		const dep = new Dep(
-			Object.assign(
-				{
-					request: context + query,
-					recursive: options.wrappedContextRecursive,
-					regExp,
-					mode: "sync"
-				},
-				contextOptions
-			),
+			{
+				request: context + query,
+				recursive: options.wrappedContextRecursive,
+				regExp,
+				mode: "sync",
+				...contextOptions
+			},
 			range,
 			valueRange
 		);
@@ -174,15 +172,13 @@ exports.create = (Dep, range, param, expr, options, contextOptions, parser) => {
 			)}$`
 		);
 		const dep = new Dep(
-			Object.assign(
-				{
-					request: context + query,
-					recursive: options.wrappedContextRecursive,
-					regExp,
-					mode: "sync"
-				},
-				contextOptions
-			),
+			{
+				request: context + query,
+				recursive: options.wrappedContextRecursive,
+				regExp,
+				mode: "sync",
+				...contextOptions
+			},
 			range,
 			valueRange
 		);
@@ -214,15 +210,13 @@ exports.create = (Dep, range, param, expr, options, contextOptions, parser) => {
 		return dep;
 	} else {
 		const dep = new Dep(
-			Object.assign(
-				{
-					request: options.exprContextRequest,
-					recursive: options.exprContextRecursive,
-					regExp: options.exprContextRegExp,
-					mode: "sync"
-				},
-				contextOptions
-			),
+			{
+				request: options.exprContextRequest,
+				recursive: options.exprContextRecursive,
+				regExp: options.exprContextRegExp,
+				mode: "sync",
+				...contextOptions
+			},
 			range,
 			param.range
 		);

lib/dependencies/ImportParserPlugin.js

@@ -175,9 +175,10 @@ class ImportParserPlugin {
 					parser.state.current.addDependency(dep);
 				} else {
 					const depBlock = new ImportDependenciesBlock(
-						Object.assign(groupOptions, {
+						{
+							...groupOptions,
 							name: chunkName
-						}),
+						},
 						expr.loc,
 						param.string,
 						expr.range

lib/ids/HashedModuleIdsPlugin.js

@@ -23,15 +23,13 @@ class HashedModuleIdsPlugin {
 		validateOptions(schema, options || {}, "Hashed Module Ids Plugin");
 
 		/** @type {HashedModuleIdsPluginOptions} */
-		this.options = Object.assign(
-			{
-				context: null,
-				hashFunction: "md4",
-				hashDigest: "base64",
-				hashDigestLength: 4
-			},
-			options
-		);
+		this.options = {
+			context: null,
+			hashFunction: "md4",
+			hashDigest: "base64",
+			hashDigestLength: 4,
+			...options
+		};
 	}
 
 	apply(compiler) {

lib/node/NodeSourcePlugin.js

@@ -38,7 +38,7 @@ module.exports = class NodeSourcePlugin {
 
 					let localOptions = options;
 					if (parserOptions.node) {
-						localOptions = Object.assign({}, localOptions, parserOptions.node);
+						localOptions = { ...localOptions, ...parserOptions.node };
 					}
 
 					if (localOptions.global) {

lib/optimize/ConcatenatedModule.js

@@ -1231,9 +1231,10 @@ class ConcatenatedModule extends Module {
 			moduleToInfoMap
 		);
 
-		const innerContext = Object.assign({}, context, {
+		const innerContext = {
+			...context,
 			dependencyTemplates: innerDependencyTemplates
-		});
+		};
 
 		const set = new Set([
 			RuntimeGlobals.exports, // TODO check if really used

lib/optimize/RuntimeChunkPlugin.js

@@ -11,12 +11,10 @@ const { STAGE_ADVANCED } = require("../OptimizationStages");
 
 class RuntimeChunkPlugin {
 	constructor(options) {
-		this.options = Object.assign(
-			{
-				name: entrypoint => `runtime~${entrypoint.name}`
-			},
-			options
-		);
+		this.options = {
+			name: entrypoint => `runtime~${entrypoint.name}`,
+			...options
+		};
 	}
 
 	/**

lib/optimize/SplitChunksPlugin.js

@@ -239,7 +239,7 @@ const normalizeSizes = value => {
 			javascript: value
 		};
 	} else if (typeof value === "object" && value !== null) {
-		return Object.assign({}, value);
+		return { ...value };
 	} else {
 		return {};
 	}
@@ -383,9 +383,7 @@ const normalizeCacheGroups = cacheGroups => {
 					if (result) {
 						const groups = Array.isArray(result) ? result : [result];
 						for (const group of groups) {
-							results.push(
-								createCacheGroupSource(Object.assign({ key }, group))
-							);
+							results.push(createCacheGroupSource({ key, ...group }));
 						}
 					}
 				} else {
@@ -393,9 +391,7 @@ const normalizeCacheGroups = cacheGroups => {
 						checkTest(option.test, module, context) &&
 						checkModuleType(option.type, module)
 					) {
-						results.push(
-							createCacheGroupSource(Object.assign({ key }, option))
-						);
+						results.push(createCacheGroupSource({ key, ...option }));
 					}
 				}
 			}
@@ -1006,10 +1002,7 @@ module.exports = class SplitChunksPlugin {
 							hasNonZeroSizes(item.cacheGroup.minRemainingSize)
 						) {
 							const chunk = validChunks[0];
-							const chunkSizes = Object.assign(
-								{},
-								chunkGraph.getChunkModulesSizes(chunk)
-							);
+							const chunkSizes = { ...chunkGraph.getChunkModulesSizes(chunk) };
 							for (const key of Object.keys(item.sizes)) {
 								chunkSizes[key] -= item.sizes[key];
 							}

lib/serialization/ObjectMiddleware.js

@@ -261,32 +261,30 @@ class ObjectMiddleware extends SerializerMiddleware {
 		let currentPosTypeLookup = 0;
 		const objectTypeLookup = new Map();
 		const cycleStack = new Set();
-		const ctx = Object.assign(
-			{
-				write(value) {
-					process(value);
-				},
-				snapshot() {
-					return {
-						length: result.length,
-						cycleStackSize: cycleStack.size,
-						referenceableSize: referenceable.size,
-						currentPos,
-						objectTypeLookupSize: objectTypeLookup.size,
-						currentPosTypeLookup
-					};
-				},
-				rollback(snapshot) {
-					result.length = snapshot.length;
-					setSetSize(cycleStack, snapshot.cycleStackSize);
-					setMapSize(referenceable, snapshot.referenceableSize);
-					currentPos = snapshot.currentPos;
-					setMapSize(objectTypeLookup, snapshot.objectTypeLookupSize);
-					currentPosTypeLookup = snapshot.currentPosTypeLookup;
-				}
+		const ctx = {
+			write(value) {
+				process(value);
 			},
-			context
-		);
+			snapshot() {
+				return {
+					length: result.length,
+					cycleStackSize: cycleStack.size,
+					referenceableSize: referenceable.size,
+					currentPos,
+					objectTypeLookupSize: objectTypeLookup.size,
+					currentPosTypeLookup
+				};
+			},
+			rollback(snapshot) {
+				result.length = snapshot.length;
+				setSetSize(cycleStack, snapshot.cycleStackSize);
+				setMapSize(referenceable, snapshot.referenceableSize);
+				currentPos = snapshot.currentPos;
+				setMapSize(objectTypeLookup, snapshot.objectTypeLookupSize);
+				currentPosTypeLookup = snapshot.currentPosTypeLookup;
+			},
+			...context
+		};
 		const process = item => {
 			// check if we can emit a reference
 			const ref = referenceable.get(item);
@@ -394,14 +392,12 @@ class ObjectMiddleware extends SerializerMiddleware {
 		let currentPosTypeLookup = 0;
 		const objectTypeLookup = new Map();
 		const result = [];
-		const ctx = Object.assign(
-			{
-				read() {
-					return decodeValue();
-				}
+		const ctx = {
+			read() {
+				return decodeValue();
 			},
-			context
-		);
+			...context
+		};
 		const decodeValue = () => {
 			const item = read();
 

lib/serialization/Serializer.js

@@ -11,7 +11,7 @@ class Serializer {
 	}
 
 	serialize(obj, context) {
-		const ctx = Object.assign({}, context, this.context);
+		const ctx = { ...context, ...this.context };
 		return new Promise((resolve, reject) =>
 			resolve(
 				this.middlewares.reduce((last, middleware) => {
@@ -32,7 +32,7 @@ class Serializer {
 	}
 
 	deserialize(context) {
-		const ctx = Object.assign({}, context, this.context);
+		const ctx = { ...context, ...this.context };
 		return Promise.resolve().then(() =>
 			this.middlewares.reduceRight((last, middleware) => {
 				if (last instanceof Promise)

lib/stats/DefaultStatsFactoryPlugin.js

@@ -50,6 +50,7 @@ const {
  * @property {string} modulesSort
  * @property {string} assetsSort
  * @property {Function[]} excludeAssets
+ * @property {Function[]} excludeModules
  * @property {Function[]} warningsFilter
  * @property {number} maxModules
  * @property {any} _env
@@ -708,33 +709,25 @@ const FILTER = {
 			if (excluded) return false;
 		}
 	},
-	"compilation.modules": Object.assign(
-		{
-			excludeModules: EXCLUDE_MODULES_FILTER("module"),
-			"!orphanModules": (module, { compilation: { chunkGraph } }) => {
-				if (chunkGraph.getNumberOfModuleChunks(module) === 0) return false;
-			}
+	"compilation.modules": ({
+		excludeModules: EXCLUDE_MODULES_FILTER("module"),
+		"!orphanModules": (module, { compilation: { chunkGraph } }) => {
+			if (chunkGraph.getNumberOfModuleChunks(module) === 0) return false;
 		},
-		BASE_MODULES_FILTER
-	),
-	"module.modules": Object.assign(
-		{
-			excludeModules: EXCLUDE_MODULES_FILTER("nested")
-		},
-		BASE_MODULES_FILTER
-	),
-	"chunk.modules": Object.assign(
-		{
-			excludeModules: EXCLUDE_MODULES_FILTER("chunk")
-		},
-		BASE_MODULES_FILTER
-	),
-	"chunk.rootModules": Object.assign(
-		{
-			excludeModules: EXCLUDE_MODULES_FILTER("root-of-chunk")
-		},
-		BASE_MODULES_FILTER
-	)
+		...BASE_MODULES_FILTER
+	}),
+	"module.modules": ({
+		excludeModules: EXCLUDE_MODULES_FILTER("nested"),
+		...BASE_MODULES_FILTER
+	}),
+	"chunk.modules": ({
+		excludeModules: EXCLUDE_MODULES_FILTER("chunk"),
+		...BASE_MODULES_FILTER
+	}),
+	"chunk.rootModules": ({
+		excludeModules: EXCLUDE_MODULES_FILTER("root-of-chunk"),
+		...BASE_MODULES_FILTER
+	})
 };
 
 /** @type {Record<string, (module: Module, context: UsualContext, options: UsualOptions, idx: number, i: number) => boolean | undefined>} */

lib/stats/DefaultStatsPrinterPlugin.js

@@ -73,11 +73,10 @@ const SIMPLE_PRINTERS = {
 	"compilation.entrypoints": (entrypoints, context, printer) =>
 		Array.isArray(entrypoints)
 			? undefined
-			: printer.print(
-					context.type,
-					Object.values(entrypoints),
-					Object.assign({}, context, { chunkGroupKind: "Entrypoint" })
-			  ),
+			: printer.print(context.type, Object.values(entrypoints), ({
+					...context,
+					chunkGroupKind: "Entrypoint"
+			  })),
 	"compilation.namedChunkGroups": (namedChunkGroups, context, printer) => {
 		if (!Array.isArray(namedChunkGroups)) {
 			const {
@@ -90,11 +89,10 @@ const SIMPLE_PRINTERS = {
 						!Object.prototype.hasOwnProperty.call(entrypoints, group.name)
 				);
 			}
-			return printer.print(
-				context.type,
-				chunkGroups,
-				Object.assign({}, context, { chunkGroupKind: "Chunk Group" })
-			);
+			return printer.print(context.type, chunkGroups, ({
+				...context,
+				chunkGroupKind: "Chunk Group"
+			}));
 		}
 	},
 	"compilation.assetsByChunkName": () => "",

lib/stats/StatsFactory.js

@@ -90,10 +90,11 @@ class StatsFactory {
 	}
 
 	create(type, data, baseContext) {
-		const context = Object.assign({}, baseContext, {
+		const context = {
+			...baseContext,
 			type,
 			[type]: data
-		});
+		};
 		if (Array.isArray(data)) {
 			// run filter on unsorted items
 			const items = forEachLevelFilter(
@@ -125,9 +126,10 @@ class StatsFactory {
 
 			// for each item
 			const resultItems = items2.map((item, i) => {
-				const itemContext = Object.assign({}, context, {
+				const itemContext = {
+					...context,
 					_index: i
-				});
+				};
 
 				// run getItemName
 				const itemName = forEachLevel(this.hooks.getItemName, `${type}[]`, h =>

lib/stats/StatsPrinter.js

@@ -62,10 +62,11 @@ class StatsPrinter {
 	}
 
 	print(type, object, baseContext) {
-		const context = Object.assign({}, baseContext, {
+		const context = {
+			...baseContext,
 			type,
 			[type]: object
-		});
+		};
 
 		let printResult = forEachLevel(this.hooks.print, type, hook =>
 			hook.call(object, context)
@@ -77,9 +78,10 @@ class StatsPrinter {
 					h.call(sortedItems, context)
 				);
 				const printedItems = sortedItems.map((item, i) => {
-					const itemContext = Object.assign({}, context, {
+					const itemContext = {
+						...context,
 						_index: i
-					});
+					};
 					const itemName = forEachLevel(
 						this.hooks.getItemName,
 						`${type}[]`,
@@ -105,15 +107,12 @@ class StatsPrinter {
 					h.call(elements, context)
 				);
 				const printedElements = elements.map(element => {
-					const content = this.print(
-						`${type}.${element}`,
-						object[element],
-						Object.assign({}, context, {
-							_parent: object,
-							_element: element,
-							[element]: object[element]
-						})
-					);
+					const content = this.print(`${type}.${element}`, object[element], {
+						...context,
+						_parent: object,
+						_element: element,
+						[element]: object[element]
+					});
 					return { element, content };
 				});
 				printResult = forEachLevel(this.hooks.printElements, type, h =>

lib/util/cleverMerge.js

@@ -41,7 +41,7 @@ const cachedCleverMerge = (first, second) => {
  * @returns {object} merged object of first and second object
  */
 const cleverMerge = (first, second) => {
-	const newObject = Object.assign({}, first);
+	const newObject = { ...first };
 	for (const key of Object.keys(second)) {
 		if (!(key in newObject)) {
 			newObject[key] = second[key];

test/Errors.test.js

@@ -92,7 +92,7 @@ const defaults = {
 
 async function compile(options) {
 	const stats = await new Promise((resolve, reject) => {
-		const compiler = webpack(Object.assign({}, defaults.options, options));
+		const compiler = webpack({ ...defaults.options, ...options });
 		if (options.mode === "production") {
 			if (options.optimization) options.optimization.minimize = true;
 			else options.optimization = { minimize: true };

test/TestCases.template.js

@@ -97,11 +97,10 @@ const describeCases = config => {
 								mode: config.mode || "none",
 								optimization: config.mode
 									? NO_EMIT_ON_ERRORS_OPTIMIZATIONS
-									: Object.assign(
-											{},
-											config.optimization,
-											DEFAULT_OPTIMIZATIONS
-									  ),
+									: {
+											...config.optimization,
+											...DEFAULT_OPTIMIZATIONS
+									  },
 								performance: {
 									hints: false
 								},
@@ -109,15 +108,11 @@ const describeCases = config => {
 									__dirname: "mock",
 									__filename: "mock"
 								},
-								cache:
-									config.cache &&
-									Object.assign(
-										{
-											loglevel: "warning",
-											cacheDirectory
-										},
-										config.cache
-									),
+								cache: config.cache && {
+									loglevel: "warning",
+									cacheDirectory,
+									...config.cache
+								},
 								output: {
 									pathinfo: true,
 									path: outputDirectory,

test/cases/loaders/issue-2299/loader/index.js

@@ -6,20 +6,26 @@ module.exports = function(content) {
 		json.imports,
 		function(url, callback) {
 			this.loadModule(url, function(err, source, map, module) {
-				if(err) {
+				if (err) {
 					return callback(err);
 				}
 				callback(null, JSON.parse(source));
 			});
 		}.bind(this),
 		function(err, results) {
-			if(err) {
+			if (err) {
 				return cb(err);
 			}
 			// Combine all the results into one object and return it
-			cb(null, "module.exports = " + JSON.stringify(results.reduce(function(prev, result) {
-				return Object.assign({}, prev, result);
-			}, json)));
+			cb(
+				null,
+				"module.exports = " +
+					JSON.stringify(
+						results.reduce(function(prev, result) {
+							return { ...prev, ...result };
+						}, json)
+					)
+			);
 		}
 	);
 };

test/compareLocations.unittest.js

@@ -2,13 +2,11 @@
 
 const { compareLocations } = require("../lib/util/comparators");
 const createPosition = overrides => {
-	return Object.assign(
-		{
-			line: 10,
-			column: 5
-		},
-		overrides
-	);
+	return {
+		line: 10,
+		column: 5,
+		...overrides
+	};
 };
 
 const createLocation = (start, end, index) => {

test/statsCases/filter-warnings/webpack.config.js

@@ -46,11 +46,8 @@ module.exports = [
 	["should not filter"],
 	[/should not filter/],
 	[warnings => false]
-].map(filter =>
-	Object.assign({}, baseConfig, {
-		name: Array.isArray(filter) ? `[${filter}]` : `${filter}`,
-		stats: Object.assign({}, baseConfig.stats, {
-			warningsFilter: filter
-		})
-	})
-);
+].map(filter => ({
+	...baseConfig,
+	name: Array.isArray(filter) ? `[${filter}]` : `${filter}`,
+	stats: { ...baseConfig.stats, warningsFilter: filter }
+}));

test/statsCases/issue-7577/webpack.config.js

@@ -16,31 +16,25 @@ const base = {
 	}
 };
 module.exports = [
-	Object.assign(
-		{
-			entry: "./a.js",
-			output: {
-				filename: "a-[name]-[chunkhash].js"
-			}
+	{
+		entry: "./a.js",
+		output: {
+			filename: "a-[name]-[chunkhash].js"
 		},
-		base
-	),
-	Object.assign(
-		{
-			entry: "./b.js",
-			output: {
-				filename: "b-[name]-[chunkhash].js"
-			}
+		...base
+	},
+	{
+		entry: "./b.js",
+		output: {
+			filename: "b-[name]-[chunkhash].js"
 		},
-		base
-	),
-	Object.assign(
-		{
-			entry: "./c.js",
-			output: {
-				filename: "c-[name]-[chunkhash].js"
-			}
+		...base
+	},
+	{
+		entry: "./c.js",
+		output: {
+			filename: "c-[name]-[chunkhash].js"
 		},
-		base
-	)
+		...base
+	}
 ];

test/statsCases/named-chunk-groups/webpack.config.js

@@ -32,16 +32,12 @@ const config = {
 };
 
 module.exports = [
-	Object.assign(
-		{
-			stats: Object.assign({ entrypoints: false, chunkGroups: true }, stats)
-		},
-		config
-	),
-	Object.assign(
-		{
-			stats: Object.assign({ entrypoints: true, chunkGroups: true }, stats)
-		},
-		config
-	)
+	{
+		stats: { entrypoints: false, chunkGroups: true, ...stats },
+		...config
+	},
+	{
+		stats: { entrypoints: true, chunkGroups: true, ...stats },
+		...config
+	}
 ];

test/statsCases/runtime-chunk-integration/webpack.config.js

@@ -18,7 +18,8 @@ const baseConfig = {
 	]
 };
 
-const withoutNamedEntry = Object.assign({}, baseConfig, {
+const withoutNamedEntry = {
+	...baseConfig,
 	name: "base",
 	entry: {
 		main1: "./main1"
@@ -26,9 +27,10 @@ const withoutNamedEntry = Object.assign({}, baseConfig, {
 	optimization: {
 		runtimeChunk: "single"
 	}
-});
+};
 
-const withNamedEntry = Object.assign({}, baseConfig, {
+const withNamedEntry = {
+	...baseConfig,
 	name: "manifest is named entry",
 	entry: {
 		main1: "./main1",
@@ -39,6 +41,6 @@ const withNamedEntry = Object.assign({}, baseConfig, {
 			name: "manifest"
 		}
 	}
-});
+};
 
 module.exports = [withoutNamedEntry, withNamedEntry];