@wordpress/block-editor/src/utils/object.js

Generic block editor.

/**
 * Immutably sets a value inside an object. Like `lodash#set`, but returning a
 * new object. Treats nullish initial values as empty objects. Clones any
 * nested objects. Supports arrays, too.
 *
 * @param {Object}              object Object to set a value in.
 * @param {number|string|Array} path   Path in the object to modify.
 * @param {*}                   value  New value to set.
 * @return {Object} Cloned object with the new value set.
 */
export function setImmutably( object, path, value ) {
	// Normalize path
	path = Array.isArray( path ) ? [ ...path ] : [ path ];

	// Shallowly clone the base of the object
	object = Array.isArray( object ) ? [ ...object ] : { ...object };

	const leaf = path.pop();

	// Traverse object from root to leaf, shallowly cloning at each level
	let prev = object;
	for ( const key of path ) {
		const lvl = prev[ key ];
		prev = prev[ key ] = Array.isArray( lvl ) ? [ ...lvl ] : { ...lvl };
	}

	prev[ leaf ] = value;

	return object;
}

/**
 * Helper util to return a value from a certain path of the object.
 * Path is specified as either:
 * - a string of properties, separated by dots, for example: "x.y".
 * - an array of properties, for example `[ 'x', 'y' ]`.
 * You can also specify a default value in case the result is nullish.
 *
 * @param {Object}       object       Input object.
 * @param {string|Array} path         Path to the object property.
 * @param {*}            defaultValue Default value if the value at the specified path is nullish.
 * @return {*} Value of the object property at the specified path.
 */
export const getValueFromObjectPath = ( object, path, defaultValue ) => {
	const arrayPath = Array.isArray( path ) ? path : path.split( '.' );
	let value = object;
	arrayPath.forEach( ( fieldName ) => {
		value = value?.[ fieldName ];
	} );
	return value ?? defaultValue;
};

/**
 * Helper util to filter out objects with duplicate values for a given property.
 *
 * @param {Object[]} array    Array of objects to filter.
 * @param {string}   property Property to filter unique values by.
 *
 * @return {Object[]} Array of objects with unique values for the specified property.
 */
export function uniqByProperty( array, property ) {
	const seen = new Set();
	return array.filter( ( item ) => {
		const value = item[ property ];
		return seen.has( value ) ? false : seen.add( value );
	} );
}