Merge pull request #7819 from webpack/refactor/template_es6

Convert Template to ES6

lib/Template.js

@@ -27,7 +27,7 @@ const MATCH_PADDED_HYPHENS_REPLACE_REGEX = /^-|-$/g;
 /**
  * @typedef {Object} HasId
  * @property {number | string} id
- * */
+ */
 
 /**
  * @typedef {function(Module, number): boolean} ModuleFilterPredicate
@@ -39,8 +39,8 @@ const MATCH_PADDED_HYPHENS_REPLACE_REGEX = /^-|-$/g;
  * @returns {-1|0|1} the sort value
  */
 const stringifyIdSortPredicate = (a, b) => {
-	var aId = a.id + "";
-	var bId = b.id + "";
+	const aId = a.id + "";
+	const bId = b.id + "";
 	if (aId < bId) return -1;
 	if (aId > bId) return 1;
 	return 0;
@@ -59,6 +59,7 @@ class Template {
 			.replace(INDENT_MULTILINE_REGEX, "")
 			.replace(LINE_SEPARATOR_REGEX, "\n");
 	}
+
 	/**
 	 * @param {string} str the string converted to identifier
 	 * @returns {string} created identifier
@@ -128,31 +129,28 @@ class Template {
 
 	/**
 	 *
-	 * @param {string | string[]} str string to convert to identity
+	 * @param {string | string[]} s string to convert to identity
 	 * @returns {string} converted identity
 	 */
-	static indent(str) {
-		if (Array.isArray(str)) {
-			return str.map(Template.indent).join("\n");
+	static indent(s) {
+		if (Array.isArray(s)) {
+			return s.map(Template.indent).join("\n");
 		} else {
-			str = str.trimRight();
+			const str = s.trimRight();
 			if (!str) return "";
-			var ind = str[0] === "\n" ? "" : "\t";
+			const ind = str[0] === "\n" ? "" : "\t";
 			return ind + str.replace(/\n([^\n])/g, "\n\t$1");
 		}
 	}
 
 	/**
 	 *
-	 * @param {string|string[]} str string to create prefix for
+	 * @param {string|string[]} s string to create prefix for
 	 * @param {string} prefix prefix to compose
 	 * @returns {string} returns new prefix string
 	 */
-	static prefix(str, prefix) {
-		if (Array.isArray(str)) {
-			str = str.join("\n");
-		}
-		str = str.trim();
+	static prefix(s, prefix) {
+		const str = Template.asString(s).trim();
 		if (!str) return "";
 		const ind = str[0] === "\n" ? "" : prefix;
 		return ind + str.replace(/\n([^\n])/g, "\n" + prefix + "$1");
@@ -181,8 +179,8 @@ class Template {
 	 * or false if not every module has a number based id
 	 */
 	static getModulesArrayBounds(modules) {
-		var maxId = -Infinity;
-		var minId = Infinity;
+		let maxId = -Infinity;
+		let minId = Infinity;
 		for (const module of modules) {
 			if (typeof module.id !== "number") return false;
 			if (maxId < module.id) maxId = /** @type {number} */ (module.id);
@@ -192,15 +190,11 @@ class Template {
 			// add minId x ',' instead of 'Array(minId).concat(…)'
 			minId = 0;
 		}
-		var objectOverhead = modules
-			.map(module => {
-				var idLength = (module.id + "").length;
-				return idLength + 2;
-			})
-			.reduce((a, b) => {
-				return a + b;
-			}, -1);
-		var arrayOverhead = minId === 0 ? maxId : 16 + ("" + minId).length + maxId;
+		const objectOverhead = modules
+			.map(module => (module.id + "").length + 2)
+			.reduce((a, b) => a + b, -1);
+		const arrayOverhead =
+			minId === 0 ? maxId : 16 + ("" + minId).length + maxId;
 		return arrayOverhead < objectOverhead ? [minId, maxId] : false;
 	}
 
@@ -217,13 +211,13 @@ class Template {
 		filterFn,
 		moduleTemplate,
 		dependencyTemplates,
-		prefix
+		prefix = ""
 	) {
-		if (!prefix) prefix = "";
-		var source = new ConcatSource();
+		const source = new ConcatSource();
 		const modules = chunk.getModules().filter(filterFn);
+		let removedModules;
 		if (chunk instanceof HotUpdateChunk) {
-			var removedModules = chunk.removedModules;
+			removedModules = chunk.removedModules;
 		}
 		if (
 			modules.length === 0 &&
@@ -233,7 +227,7 @@ class Template {
 			return source;
 		}
 		/** @type {{id: string|number, source: Source|string}[]} */
-		var allModules = modules.map(module => {
+		const allModules = modules.map(module => {
 			return {
 				id: module.id,
 				source: moduleTemplate.render(module, dependencyTemplates, {
@@ -249,38 +243,45 @@ class Template {
 				});
 			}
 		}
-		var bounds = Template.getModulesArrayBounds(allModules);
-
+		const bounds = Template.getModulesArrayBounds(allModules);
 		if (bounds) {
 			// Render a spare array
-			var minId = bounds[0];
-			var maxId = bounds[1];
-			if (minId !== 0) source.add("Array(" + minId + ").concat(");
+			const minId = bounds[0];
+			const maxId = bounds[1];
+			if (minId !== 0) {
+				source.add(`Array(${minId}).concat(`);
+			}
 			source.add("[\n");
 			const modules = new Map();
 			for (const module of allModules) {
 				modules.set(module.id, module);
 			}
-			for (var idx = minId; idx <= maxId; idx++) {
-				var module = modules.get(idx);
-				if (idx !== minId) source.add(",\n");
-				source.add("/* " + idx + " */");
+			for (let idx = minId; idx <= maxId; idx++) {
+				const module = modules.get(idx);
+				if (idx !== minId) {
+					source.add(",\n");
+				}
+				source.add(`/* ${idx} */`);
 				if (module) {
 					source.add("\n");
 					source.add(module.source);
 				}
 			}
 			source.add("\n" + prefix + "]");
-			if (minId !== 0) source.add(")");
+			if (minId !== 0) {
+				source.add(")");
+			}
 		} else {
 			// Render an object
 			source.add("{\n");
 			allModules.sort(stringifyIdSortPredicate).forEach((module, idx) => {
-				if (idx !== 0) source.add(",\n");
+				if (idx !== 0) {
+					source.add(",\n");
+				}
 				source.add(`\n/***/ ${JSON.stringify(module.id)}:\n`);
 				source.add(module.source);
 			});
-			source.add("\n\n" + prefix + "}");
+			source.add(`\n\n${prefix}}`);
 		}
 		return source;
 	}