es-toolkit/dist/compat/array/findLast.mjs

A state-of-the-art, high-performance JavaScript utility library with a small bundle size and strong type annotations.

import { identity } from "../../function/identity.mjs";
import { iteratee } from "../util/iteratee.mjs";
import { toInteger } from "../util/toInteger.mjs";
//#region src/compat/array/findLast.ts
/**
* Finds the last item in an object that has a specific property, where the property name is provided as a PropertyKey.
*
* @template T
* @param collection - The array or object to search through.
* @param [predicate=identity] - The criteria to match. It can be a function, a partial object, a key-value pair, or a property name.
* @param [fromIndex] - The index to start the search from, defaults to collection.length-1 for arrays or Object.keys(collection).length-1 for objects.
* @returns The last property value that has the specified property, or `undefined` if no match is found.
*
* @example
* // Using a property name
* const obj = { a: { id: 1, name: 'Alice' }, b: { id: 2 }, c: { id: 3, name: 'Bob' } };
* const result = findLast(obj, 'name');
* console.log(result); // { id: 3, name: 'Bob' }
*/
function findLast(collection, predicate = identity, fromIndex) {
	if (!collection) return;
	const length = Array.isArray(collection) ? collection.length : Object.keys(collection).length;
	fromIndex = toInteger(fromIndex ?? length - 1);
	if (fromIndex < 0) fromIndex = Math.max(length + fromIndex, 0);
	else fromIndex = Math.min(fromIndex, length - 1);
	const doesMatch = iteratee(predicate);
	if (!Array.isArray(collection)) {
		const keys = Object.keys(collection);
		for (let i = fromIndex; i >= 0; i--) {
			const key = keys[i];
			const value = collection[key];
			if (doesMatch(value, key, collection)) return value;
		}
		return;
	}
	return collection.slice(0, fromIndex + 1).findLast(doesMatch);
}
//#endregion
export { findLast };