Create unused.js

Author: LeaVerou

src/util/unused.js

@@ -0,0 +1,83 @@
+/**
+ * Utility functions that are not used anywhere, to have handy when needed
+ */
+
+/** Copy methods from one class onto another */
+export function extend (Class, Mixin) {
+	let members = Object.getOwnPropertyDescriptors(Mixin.prototype);
+
+	for (let key in members) {
+		if (key in Class.prototype) {
+			continue;
+		}
+
+		Object.defineProperty(Class.prototype, key, members[key]);
+	}
+
+	let statics = Object.getOwnPropertyDescriptors(Mixin);
+
+	for (let key in statics) {
+		if (key in Class) {
+			continue;
+		}
+
+		Object.defineProperty(Class, key, statics[key]);
+	}
+}
+
+export const sort = {
+	alphanumeric: (a, b) => a.localeCompare(b),
+	alphanumericDesc: (a, b) => b.localeCompare(a),
+	numeric: (a, b) => a - b,
+	numericDesc: (a, b) => b - a,
+	count: (a, b) => a.length - a.length,
+	countDesc: (a, b) => b.length - a.length,
+};
+
+export function groupBy (arr, fn) {
+	let grouped = new Map();
+	let isFunction = typeof fn === 'function';
+
+	for (let item of arr) {
+		let key = isFunction ? fn(item) : item[fn];
+		let items = grouped.get(key);
+
+		if (!items) {
+			items = [];
+			grouped.set(key, items);
+		}
+
+		items.push(item);
+	}
+
+	// if (sortValues) {
+	// 	grouped = sortObjectValues(grouped, sortValues);
+	// }
+	// else if (sortKeys) {
+	// 	grouped = sortObjectKeys(grouped, sortKeys);
+	// }
+
+	return grouped;
+}
+
+export function sortObjectKeys (obj, fn = sort.alphanumeric) {
+	let sortedKeys = Object.keys(obj).sort(fn);
+	let sortedObj = {};
+
+	for (let key of sortedKeys) {
+		sortedObj[key] = obj[key];
+	}
+
+	return sortedObj;
+}
+
+export function sortObjectValues (obj, fn = sort.countDesc) {
+	let sortedEntries = Object.entries(obj).sort((a, b) => fn(a[1], b[1]));
+	let sortedObj = {};
+
+	for (let [key, value] of sortedEntries) {
+		sortedObj[key] = value;
+	}
+
+	return sortedObj;
+}