Upgrade to Prettier 2

.prettierrc.js

@@ -2,6 +2,8 @@ module.exports = {
 	printWidth: 80,
 	useTabs: true,
 	tabWidth: 2,
+	trailingComma: "none",
+	arrowParens: "avoid",
 	overrides: [
 		{
 			files: "*.json",

lib/ContextModule.js

@@ -104,7 +104,7 @@ class ContextModule extends Module {
 		// Info from Factory
 		this.resolveDependencies = resolveDependencies;
 		/** @type {ContextModuleOptions} */
-		this.options = ({
+		this.options = {
 			resource: resource,
 			resourceQuery: resourceQuery,
 			mode: options.mode,
@@ -116,7 +116,7 @@ class ContextModule extends Module {
 			chunkName: options.chunkName,
 			groupOptions: options.groupOptions,
 			namespaceObject: options.namespaceObject
-		});
+		};
 		if (options.resolveOptions !== undefined) {
 			this.resolveOptions = options.resolveOptions;
 		}

lib/EvalSourceMapDevToolPlugin.js

@@ -79,8 +79,7 @@ class EvalSourceMapDevToolPlugin {
 						} else if (m instanceof ConcatenatedModule) {
 							const concatModule = /** @type {ConcatenatedModule} */ (m);
 							if (concatModule.rootModule instanceof NormalModule) {
-								const module =
-									/** @type {NormalModule} */ (concatModule.rootModule);
+								const module = /** @type {NormalModule} */ (concatModule.rootModule);
 								if (!matchModule(module.resource)) {
 									return source;
 								}

lib/Module.js

@@ -703,11 +703,7 @@ class Module extends DependenciesBlock {
 		const sources = this.codeGeneration(sourceContext).sources;
 		return sourceContext.type
 			? sources.get(sourceContext.type)
-			: sources.get(
-					this.getSourceTypes()
-						.values()
-						.next().value
-			  );
+			: sources.get(this.getSourceTypes().values().next().value);
 	}
 
 	/**

lib/ModuleDependencyError.js

@@ -20,10 +20,7 @@ class ModuleDependencyError extends WebpackError {
 		super(err.message);
 
 		this.name = "ModuleDependencyError";
-		this.details = err.stack
-			.split("\n")
-			.slice(1)
-			.join("\n");
+		this.details = err.stack.split("\n").slice(1).join("\n");
 		this.module = module;
 		this.loc = loc;
 		this.error = err;

lib/ModuleDependencyWarning.js

@@ -19,10 +19,7 @@ module.exports = class ModuleDependencyWarning extends WebpackError {
 		super(err.message);
 
 		this.name = "ModuleDependencyWarning";
-		this.details = err.stack
-			.split("\n")
-			.slice(1)
-			.join("\n");
+		this.details = err.stack.split("\n").slice(1).join("\n");
 		this.module = module;
 		this.loc = loc;
 		this.error = err;

lib/ModuleFilenameHelpers.js

@@ -88,10 +88,7 @@ ModuleFilenameHelpers.createFilename = (
 		shortIdentifier = module.readableIdentifier(requestShortener);
 		identifier = requestShortener.shorten(module.identifier());
 		moduleId = chunkGraph.getModuleId(module);
-		absoluteResourcePath = module
-			.identifier()
-			.split("!")
-			.pop();
+		absoluteResourcePath = module.identifier().split("!").pop();
 		hash = getHash(identifier);
 	}
 	const resource = shortIdentifier.split("!").pop();

lib/config/normalization.js

@@ -117,9 +117,7 @@ const getNormalizedWebpackOptions = config => {
 		entry: nestedConfig(config.entry, entry => {
 			if (typeof entry === "function") {
 				return () =>
-					Promise.resolve()
-						.then(entry)
-						.then(getNormalizedEntryStatic);
+					Promise.resolve().then(entry).then(getNormalizedEntryStatic);
 			}
 			return getNormalizedEntryStatic(entry);
 		}),

lib/javascript/JavascriptGenerator.js

@@ -152,8 +152,7 @@ class JavascriptGenerator extends Generator {
 	 * @returns {void}
 	 */
 	sourceDependency(module, dependency, initFragments, source, generateContext) {
-		const constructor =
-			/** @type {new (...args: any[]) => Dependency} */ (dependency.constructor);
+		const constructor = /** @type {new (...args: any[]) => Dependency} */ (dependency.constructor);
 		const template = generateContext.dependencyTemplates.get(constructor);
 		if (!template) {
 			throw new Error(

lib/optimize/ConcatenatedModule.js

@@ -907,8 +907,7 @@ class ConcatenatedModule extends Module {
 				})
 				.map(connection => ({
 					connection,
-					sourceOrder:
-						/** @type {HarmonyImportDependency} */ (connection.dependency)
+					sourceOrder: /** @type {HarmonyImportDependency} */ (connection.dependency)
 						.sourceOrder
 				}));
 			references.sort(

lib/optimize/InnerGraphPlugin.js

@@ -234,8 +234,7 @@ class InnerGraphPlugin {
 					parser.hooks.expression
 						.for(topLevelSymbolTag)
 						.tap("InnerGraphPlugin", () => {
-							const topLevelSymbol =
-								/** @type {TopLevelSymbol} */ (parser.currentTagData);
+							const topLevelSymbol = /** @type {TopLevelSymbol} */ (parser.currentTagData);
 							const currentTopLevelSymbol = InnerGraph.getTopLevelSymbol(
 								parser.state
 							);

lib/optimize/ModuleConcatenationPlugin.js

@@ -185,7 +185,8 @@ class ModuleConcatenationPlugin {
 									);
 									const importingModuleTypes = new Map(
 										Array.from(importingModules).map(
-											m => /** @type {[Module, Set<string>]} */ ([
+											m =>
+												/** @type {[Module, Set<string>]} */ ([
 													m,
 													new Set(
 														nonHarmonyConnections

lib/optimize/SplitChunksPlugin.js

@@ -1213,8 +1213,9 @@ module.exports = class SplitChunksPlugin {
 								minSizeValue > maxSizeValue
 							) {
 								const keys = chunkConfig && chunkConfig.keys;
-								const warningKey = `${keys &&
-									keys.join()} ${minSizeValue} ${maxSizeValue}`;
+								const warningKey = `${
+									keys && keys.join()
+								} ${minSizeValue} ${maxSizeValue}`;
 								if (!incorrectMinMaxSizeSet.has(warningKey)) {
 									incorrectMinMaxSizeSet.add(warningKey);
 									compilation.warnings.push(

lib/stats/DefaultStatsFactoryPlugin.js

@@ -435,8 +435,9 @@ const SIMPLE_EXTRACTORS = {
 					}
 					let message = undefined;
 					if (entry.type === LogType.time) {
-						message = `${entry.args[0]}: ${entry.args[1] * 1000 +
-							entry.args[2] / 1000000}ms`;
+						message = `${entry.args[0]}: ${
+							entry.args[1] * 1000 + entry.args[2] / 1000000
+						}ms`;
 					} else if (entry.args && entry.args.length > 0) {
 						message = util.format(entry.args[0], ...entry.args.slice(1));
 					}
@@ -500,22 +501,22 @@ const SIMPLE_EXTRACTORS = {
 				compilationAuxiliaryFileToChunks.get(asset.name) || [];
 			object.chunkNames = uniqueOrderedArray(
 				chunks,
-				c => ((c.name ? [c.name] : [])),
+				c => (c.name ? [c.name] : []),
 				compareIds
 			);
 			object.chunkIdHints = uniqueOrderedArray(
 				chunks,
-				c => (Array.from(c.idNameHints)),
+				c => Array.from(c.idNameHints),
 				compareIds
 			);
 			object.auxiliaryChunkNames = uniqueOrderedArray(
 				auxiliaryChunks,
-				c => ((c.name ? [c.name] : [])),
+				c => (c.name ? [c.name] : []),
 				compareIds
 			);
 			object.auxiliaryChunkIdHints = uniqueOrderedArray(
 				auxiliaryChunks,
-				c => (Array.from(c.idNameHints)),
+				c => Array.from(c.idNameHints),
 				compareIds
 			);
 			object.emitted = compilation.emittedAssets.has(asset.name);
@@ -986,25 +987,25 @@ const FILTER = {
 			}
 		}
 	},
-	"compilation.modules": ({
+	"compilation.modules": {
 		excludeModules: EXCLUDE_MODULES_FILTER("module"),
 		"!orphanModules": (module, { compilation: { chunkGraph } }) => {
 			if (chunkGraph.getNumberOfModuleChunks(module) === 0) return false;
 		},
 		...BASE_MODULES_FILTER
-	}),
-	"module.modules": ({
+	},
+	"module.modules": {
 		excludeModules: EXCLUDE_MODULES_FILTER("nested"),
 		...BASE_MODULES_FILTER
-	}),
-	"chunk.modules": ({
+	},
+	"chunk.modules": {
 		excludeModules: EXCLUDE_MODULES_FILTER("chunk"),
 		...BASE_MODULES_FILTER
-	}),
-	"chunk.rootModules": ({
+	},
+	"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/DefaultStatsPresetPlugin.js

@@ -152,12 +152,12 @@ const DEFAULTS = {
 	warnings: NORMAL_ON,
 	publicPath: OFF_FOR_TO_STRING,
 	logging: ({ all }, { forToString }) =>
-		(forToString && all !== false ? "info" : false),
+		forToString && all !== false ? "info" : false,
 	loggingDebug: () => [],
 	loggingTrace: OFF_FOR_TO_STRING,
 	excludeModules: () => [],
 	excludeAssets: () => [],
-	maxModules: (o, { forToString }) => ((forToString ? 15 : Infinity)),
+	maxModules: (o, { forToString }) => (forToString ? 15 : Infinity),
 	modulesSort: () => "depth",
 	chunkModulesSort: () => "name",
 	chunkRootModulesSort: () => "name",

lib/stats/DefaultStatsPrinterPlugin.js

@@ -43,11 +43,7 @@ const printSizes = (sizes, { formatSize }) => {
 	}
 };
 
-const mapLines = (str, fn) =>
-	str
-		.split("\n")
-		.map(fn)
-		.join("\n");
+const mapLines = (str, fn) => str.split("\n").map(fn).join("\n");
 
 /**
  * @param {number} n a number
@@ -84,10 +80,10 @@ const SIMPLE_PRINTERS = {
 	"compilation.entrypoints": (entrypoints, context, printer) =>
 		Array.isArray(entrypoints)
 			? undefined
-			: printer.print(context.type, Object.values(entrypoints), ({
+			: printer.print(context.type, Object.values(entrypoints), {
 					...context,
 					chunkGroupKind: "Entrypoint"
-			  })),
+			  }),
 	"compilation.namedChunkGroups": (namedChunkGroups, context, printer) => {
 		if (!Array.isArray(namedChunkGroups)) {
 			const {
@@ -100,10 +96,10 @@ const SIMPLE_PRINTERS = {
 						!Object.prototype.hasOwnProperty.call(entrypoints, group.name)
 				);
 			}
-			return printer.print(context.type, chunkGroups, ({
+			return printer.print(context.type, chunkGroups, {
 				...context,
 				chunkGroupKind: "Chunk Group"
-			}));
+			});
 		}
 	},
 	"compilation.assetsByChunkName": () => "",
@@ -152,7 +148,7 @@ const SIMPLE_PRINTERS = {
 	"asset.size": (
 		size,
 		{ asset: { isOverSizeLimit }, yellow, green, formatSize }
-	) => ((isOverSizeLimit ? yellow(formatSize(size)) : formatSize(size))),
+	) => (isOverSizeLimit ? yellow(formatSize(size)) : formatSize(size)),
 	"asset.emitted": (emitted, { green, formatFlag }) =>
 		emitted ? green(formatFlag("emitted")) : undefined,
 	"asset.comparedForEmit": (comparedForEmit, { yellow, formatFlag }) =>
@@ -167,7 +163,7 @@ const SIMPLE_PRINTERS = {
 	"asset.info.hotModuleReplacement": (
 		hotModuleReplacement,
 		{ green, formatFlag }
-	) => ((hotModuleReplacement ? green(formatFlag("hmr")) : undefined)),
+	) => (hotModuleReplacement ? green(formatFlag("hmr")) : undefined),
 
 	assetChunk: (id, { formatChunkId }) => formatChunkId(id),
 
@@ -350,8 +346,7 @@ const SIMPLE_PRINTERS = {
 		rendered ? green(formatFlag("rendered")) : undefined,
 	"chunk.recorded": (recorded, { formatFlag, green }) =>
 		recorded ? green(formatFlag("recorded")) : undefined,
-	"chunk.reason": (reason, { yellow }) =>
-		(reason ? yellow(reason) : undefined),
+	"chunk.reason": (reason, { yellow }) => (reason ? yellow(reason) : undefined),
 	"chunk.rootModules": (modules, context) => {
 		let maxModuleId = 0;
 		for (const module of modules) {
@@ -462,7 +457,7 @@ const SIMPLE_PRINTERS = {
 
 	loggingGroup: loggingGroup =>
 		loggingGroup.entries.length === 0 ? "" : undefined,
-	"loggingGroup.debug": (flag, { red }) => ((flag ? red("DEBUG") : undefined)),
+	"loggingGroup.debug": (flag, { red }) => (flag ? red("DEBUG") : undefined),
 	"loggingGroup.name": (name, { bold }) => bold(`LOG from ${name}`),
 	"loggingGroup.separator!": () => "\n",
 	"loggingGroup.filteredEntries": filteredEntries =>
@@ -830,7 +825,7 @@ const SIMPLE_ELEMENT_JOINERS = {
 			if (maxModuleId >= 10) prefix += " ";
 		}
 		return (
-			(prefix +
+			prefix +
 			joinExplicitNewLine(
 				items.filter(item => {
 					switch (item.element) {
@@ -846,13 +841,13 @@ const SIMPLE_ELEMENT_JOINERS = {
 					return true;
 				}),
 				indenter
-			))
+			)
 		);
 	},
 	chunk: items => {
 		let hasEntry = false;
 		return (
-			("chunk " +
+			"chunk " +
 			joinExplicitNewLine(
 				items.filter(item => {
 					switch (item.element) {
@@ -866,7 +861,7 @@ const SIMPLE_ELEMENT_JOINERS = {
 					return true;
 				}),
 				" "
-			))
+			)
 		);
 	},
 	"chunk.childrenByOrder[]": items => `(${joinOneLine(items)})`,
@@ -886,8 +881,8 @@ const SIMPLE_ELEMENT_JOINERS = {
 						break;
 					case "resolvedModule":
 						return (
-							(moduleReason.module !== moduleReason.resolvedModule &&
-							item.content)
+							moduleReason.module !== moduleReason.resolvedModule &&
+							item.content
 						);
 				}
 				return true;

lib/validateSchema.js

@@ -64,8 +64,7 @@ const validateSchema = (schema, options) => {
 			}
 
 			if (error.keyword === "additionalProperties") {
-				const params =
-					/** @type {import("ajv").AdditionalPropertiesParams} */ (error.params);
+				const params = /** @type {import("ajv").AdditionalPropertiesParams} */ (error.params);
 				if (
 					Object.prototype.hasOwnProperty.call(
 						DID_YOU_MEAN,

package.json

@@ -68,7 +68,7 @@
     "mini-css-extract-plugin": "^0.8.0",
     "mini-svg-data-uri": "^1.1.3",
     "open-cli": "^5.0.0",
-    "prettier": "^1.14.3",
+    "prettier": "2",
     "pretty-format": "^25.1.0",
     "pug": "^2.0.4",
     "pug-loader": "^2.4.0",

setup/setup.js

@@ -96,11 +96,7 @@ function execGetOutput(command, args, description) {
 			if (exitCode) {
 				reject(`${description} failed with exit code ${exitCode}`);
 			} else {
-				resolve(
-					Buffer.concat(buffers)
-						.toString("utf-8")
-						.trim()
-				);
+				resolve(Buffer.concat(buffers).toString("utf-8").trim());
 			}
 		});
 		const buffers = [];

test/benchmarkCases/many-modules/webpack.config.js

@@ -1,3 +1,3 @@
 module.exports = {
-	entry: "./index"
+	entry: "./index",
 };

yarn.lock

@@ -5313,7 +5313,12 @@ prettier-linter-helpers@^1.0.0:
   dependencies:
     fast-diff "^1.1.2"
 
-prettier@^1.14.3, prettier@^1.19.1:
+prettier@2:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-2.0.2.tgz#1ba8f3eb92231e769b7fcd7cb73ae1b6b74ade08"
+  integrity sha512-5xJQIPT8BraI7ZnaDwSbu5zLrB6vvi8hVV58yHQ+QK64qrY40dULy0HSRlQ2/2IdzeBpjhDkqdcFBnFeDEMVdg==
+
+prettier@^1.19.1:
   version "1.19.1"
   resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.19.1.tgz#f7d7f5ff8a9cd872a7be4ca142095956a60797cb"
   integrity sha512-s7PoyDv/II1ObgQunCbB9PdLmUcBZcnWOcxDh7O0N/UwDEsHyqkW+Qh28jW+mVuCdx7gLB0BotYI1Y6uI9iyew==