@sussudio/base/common/collections.mjs

Internal APIs for VS Code's utilities and user interface building blocks.

/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/
/**
 * Groups the collection into a dictionary based on the provided
 * group function.
 */
export function groupBy(data, groupFn) {
	const result = 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 diffSets(before, after) {
	const removed = [];
	const added = [];
	for (const element of before) {
		if (!after.has(element)) {
			removed.push(element);
		}
	}
	for (const element of after) {
		if (!before.has(element)) {
			added.push(element);
		}
	}
	return { removed, added };
}
export function diffMaps(before, after) {
	const removed = [];
	const added = [];
	for (const [index, value] of before) {
		if (!after.has(index)) {
			removed.push(value);
		}
	}
	for (const [index, value] of after) {
		if (!before.has(index)) {
			added.push(value);
		}
	}
	return { removed, added };
}
export class SetMap {
	map = new Map();
	add(key, value) {
		let values = this.map.get(key);
		if (!values) {
			values = new Set();
			this.map.set(key, values);
		}
		values.add(value);
	}
	delete(key, value) {
		const values = this.map.get(key);
		if (!values) {
			return;
		}
		values.delete(value);
		if (values.size === 0) {
			this.map.delete(key);
		}
	}
	forEach(key, fn) {
		const values = this.map.get(key);
		if (!values) {
			return;
		}
		values.forEach(fn);
	}
}