Merge commit 'be3e8236086165e5e45a5a10783823874b3f3ebd' as 'lib/vscode'

lib/vscode/src/vs/base/common/collections.ts

@@ -0,0 +1,118 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+/**
+ * An interface for a JavaScript object that
+ * acts a dictionary. The keys are strings.
+ */
+export type IStringDictionary<V> = Record<string, V>;
+
+
+/**
+ * An interface for a JavaScript object that
+ * acts a dictionary. The keys are numbers.
+ */
+export type INumberDictionary<V> = Record<number, V>;
+
+const hasOwnProperty = Object.prototype.hasOwnProperty;
+
+/**
+ * Returns an array which contains all values that reside
+ * in the given dictionary.
+ */
+export function values<T>(from: IStringDictionary<T> | INumberDictionary<T>): T[] {
+	const result: T[] = [];
+	for (let key in from) {
+		if (hasOwnProperty.call(from, key)) {
+			result.push((from as any)[key]);
+		}
+	}
+	return result;
+}
+
+/**
+ * Iterates over each entry in the provided dictionary. The iterator allows
+ * to remove elements and will stop when the callback returns {{false}}.
+ */
+export function forEach<T>(from: IStringDictionary<T> | INumberDictionary<T>, callback: (entry: { key: any; value: T; }, remove: () => void) => any): void {
+	for (let key in from) {
+		if (hasOwnProperty.call(from, key)) {
+			const result = callback({ key: key, value: (from as any)[key] }, function () {
+				delete (from as any)[key];
+			});
+			if (result === false) {
+				return;
+			}
+		}
+	}
+}
+
+/**
+ * Groups the collection into a dictionary based on the provided
+ * group function.
+ */
+export function groupBy<T>(data: T[], groupFn: (element: T) => string): IStringDictionary<T[]> {
+	const result: IStringDictionary<T[]> = Object.create(null);
+	for (const element of data) {
+		const key = groupFn(element);
+		let target = result[key];
+		if (!target) {
+			target = result[key] = [];
+		}
+		target.push(element);
+	}
+	return result;
+}
+
+export function fromMap<T>(original: Map<string, T>): IStringDictionary<T> {
+	const result: IStringDictionary<T> = Object.create(null);
+	if (original) {
+		original.forEach((value, key) => {
+			result[key] = value;
+		});
+	}
+	return result;
+}
+
+
+export class SetMap<K, V> {
+
+	private map = new Map<K, Set<V>>();
+
+	add(key: K, value: V): void {
+		let values = this.map.get(key);
+
+		if (!values) {
+			values = new Set<V>();
+			this.map.set(key, values);
+		}
+
+		values.add(value);
+	}
+
+	delete(key: K, value: V): void {
+		const values = this.map.get(key);
+
+		if (!values) {
+			return;
+		}
+
+		values.delete(value);
+
+		if (values.size === 0) {
+			this.map.delete(key);
+		}
+	}
+
+	forEach(key: K, fn: (value: V) => void): void {
+		const values = this.map.get(key);
+
+		if (!values) {
+			return;
+		}
+
+		values.forEach(fn);
+	}
+}