phase 1 for RFC webpack#6534. WebpackError / WebpackErrorArray intro

shellscape · shellscape · commit 6714bb799afe · 2018-03-21T14:00:45.000-04:00
diff --git a/lib/Compilation.js b/lib/Compilation.js
@@ -33,6 +33,7 @@ const createHash = require("./util/createHash");
 const Queue = require("./util/Queue");
 const SortableSet = require("./util/SortableSet");
 const GraphHelpers = require("./GraphHelpers");
+const WebpackErrorArray = require("./WebpackErrorArray");
 
 const byId = (a, b) => {
 	if (a.id < b.id) return -1;
@@ -241,8 +242,8 @@ class Compilation extends Tapable {
 		this.nextFreeModuleIndex2 = undefined;
 		this.additionalChunkAssets = [];
 		this.assets = {};
-		this.errors = [];
-		this.warnings = [];
+		this.errors = new WebpackErrorArray();
+		this.warnings = new WebpackErrorArray();
 		this.children = [];
 		this.dependencyFactories = new Map();
 		this.dependencyTemplates = new Map();
diff --git a/lib/Module.js b/lib/Module.js
@@ -10,6 +10,7 @@ const DependenciesBlock = require("./DependenciesBlock");
 const ModuleReason = require("./ModuleReason");
 const SortableSet = require("./util/SortableSet");
 const Template = require("./Template");
+const WebpackErrorArray = require("./WebpackErrorArray");
 
 const EMPTY_RESOLVE_OPTIONS = {};
 
@@ -41,8 +42,8 @@ class Module extends DependenciesBlock {
 		this.factoryMeta = {};
 
 		// Info from Build
-		this.warnings = [];
-		this.errors = [];
+		this.errors = new WebpackErrorArray();
+		this.warnings = new WebpackErrorArray();
 		this.buildMeta = undefined;
 		this.buildInfo = undefined;
 
diff --git a/lib/WebpackError.js b/lib/WebpackError.js
@@ -4,8 +4,81 @@
 */
 "use strict";
 
+const createHash = require("./util/createHash");
+
+const hash = Symbol();
+const meta = Symbol();
+
 module.exports = class WebpackError extends Error {
+	constructor(
+		message,
+		line = 0,
+		column = 0,
+		columnEnd = 0,
+		category = "error"
+	) {
+		// TODO: enable message assertion during construction in a commit to follow
+		// if (!message) {
+		// 	WebpackError.deprecate("message must be a non-null, non-empty value.");
+		// }
+		// TODO: enable message length limit at a commit to follow
+		// else if (message.length > 160) {
+		// 	WebpackError.deprecate("message cannot be longer than 80 characters.");
+		// }
+
+		super(message);
+
+		this[hash] = createHash("md4");
+		this[meta] = {};
+		this.category = category;
+		this.column = column;
+		this.columnEnd = columnEnd;
+		this.line = line;
+
+		// TODO: enable abstract protection at a commit to follow
+		// if (this.constructor === WebpackError) {
+		// 	const message = `A WebpackError cannot be directly constructed.`;
+		// 	WebpackError.deprecate(message);
+		// }
+	}
+
+	static deprecate(message) {
+		const err = new Error();
+		const stack = err.stack
+			.split("\n")
+			.slice(3, 4)
+			.join("\n");
+		// use process.stdout to assert the message will be displayed in
+		// environments where console has been proxied. this mimics node's
+		// util.deprecate method.
+		process.stdout.write(`DeprecationWarning: ${message}\n${stack}\n`);
+	}
+
+	get id() {
+		return this[hash];
+	}
+
 	inspect() {
 		return this.stack + (this.details ? `\n${this.details}` : "");
 	}
+
+	get meta() {
+		return this[meta];
+	}
+
+	// TODO: enable this standard output in a later PR. at present, webpack tests
+	// rely heavily on arbitrary toString() output of different errors.
+	// toString(formatFn) {
+	// 	if (formatFn) {
+	// 		return formatFn(this);
+	// 	}
+	//
+	// 	let preface = `${this.line}:${this.column} `;
+	//
+	// 	if (this.category) {
+	// 		preface += `${this.category}: `;
+	// 	}
+	//
+	// 	return `${preface}${this.message}`;
+	// }
 };
diff --git a/lib/WebpackErrorArray.js b/lib/WebpackErrorArray.js
@@ -0,0 +1,33 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Andrew Powell <andrew@shellscape.org>
+*/
+"use strict";
+
+const WebpackError = require("./WebpackError");
+
+module.exports = class WebpackErrorArray extends Array {
+	constructor(...args) {
+		// TODO: validation will be enabled in a later PR
+		// if (args.length > 0 && typeof args[0] !== "number") {
+		// 	WebpackErrorArray.validate(...args);
+		// }
+		super(...args);
+	}
+
+	push(...args) {
+		// TODO: validation will be enabled in a later PR
+		// WebpackErrorArray.validate(...args);
+		super.push(...args);
+	}
+
+	static validate(...args) {
+		for (const arg of args) {
+			if (!(arg instanceof WebpackError)) {
+				const message = `A WebpackErrorArray can only contain WebpackError objects.
+  Offending Argument: ${arg}`;
+				WebpackError.deprecate(message);
+			}
+		}
+	}
+};
diff --git a/lib/optimize/ConcatenatedModule.js b/lib/optimize/ConcatenatedModule.js
@@ -18,6 +18,7 @@ const HarmonyExportExpressionDependency = require("../dependencies/HarmonyExport
 const HarmonyExportImportedSpecifierDependency = require("../dependencies/HarmonyExportImportedSpecifierDependency");
 const HarmonyCompatibilityDependency = require("../dependencies/HarmonyCompatibilityDependency");
 const createHash = require("../util/createHash");
+const WebpackErrorArray = require("../WebpackErrorArray");
 
 const ensureNsObjSource = (
 	info,
@@ -288,8 +289,8 @@ class ConcatenatedModule extends Module {
 
 		this.dependencies = [];
 
-		this.warnings = [];
-		this.errors = [];
+		this.errors = new WebpackErrorArray();
+		this.warnings = new WebpackErrorArray();
 		this._orderedConcatenationList = this._createOrderedConcatenationList(
 			rootModule,
 			modulesSet
diff --git a/test/RemovedPlugins.unittest.js b/test/RemovedPlugins.unittest.js
@@ -4,14 +4,15 @@ require("should");
 
 describe("removed plugin errors", () => {
 	it("should error when accessing removed plugins", () => {
-		(() => webpack.optimize.UglifyJsPlugin).should.throw(
-			RemovedPluginError,
-			/webpack\.optimize\.UglifyJsPlugin has been removed, please use config\.optimization\.minimize instead\./
-		);
+		(() => webpack.optimize.UglifyJsPlugin).should.throw(RemovedPluginError, {
+			message: /webpack\.optimize\.UglifyJsPlugin has been removed, please use config\.optimization\.minimize instead\./
+		});
 
 		(() => webpack.optimize.CommonsChunkPlugin).should.throw(
 			RemovedPluginError,
-			/webpack\.optimize\.CommonsChunkPlugin has been removed, please use config\.optimization\.splitChunks instead\./
+			{
+				message: /webpack\.optimize\.CommonsChunkPlugin has been removed, please use config\.optimization\.splitChunks instead\./
+			}
 		);
 	});
 });
