flat object in javascript

import * as _ from 'lodash';

/**
 *
 * @param {object} value
 * @returns {object}
 */
export function flattenObject(value) {
    /**@type {object} */
    let toReturn = {};

    for (const i in value) {
        if (!value.hasOwnProperty(i)) {
            continue;
        }

        if (typeof value[i] == 'object') {
            const flatObject = flattenObject(value[i]);
            for (const x in flatObject) {
                if (!flatObject.hasOwnProperty(x)) continue;

                toReturn[i + '.' + x] = flatObject[x];
            }
        } else {
            toReturn[i] = value[i];
        }
    }
    return toReturn;
}


/////////////////////OR//////////////////////////////

// @ts-check

/**
 *
 * @param {object} object
 * @returns {Promise<object>}
 */
export async function flatObjectAndSeparateThemByDot(object) {
    /**@type {object} */
    const res = {};
    /**
     *
     * @param {object} obj
     * @param {string} [current]
     */
    (function recurse(obj, current) {
        if (current && _.isArray(object[current])) {
            // this condition will ignore arrays
            res[current] = object[current];
        } else {
            for (const key in obj) {
                const value = obj[key];
                // joined keys with dot
                const newKey = current ? current + '.' + key : key;
                if (value && typeof value === 'object') {
                    // it's a nested object, so do it again
                    recurse(value, newKey);
                } else {
                    // it's not an object, so set the property
                    res[newKey] = value;
                }
            }
        }
    })(object);

    return res;
}

// Typescript version
export async function flatObjectAndSeparateThemByDot(
    object: any,
): Promise<any> {
    const res: any = {};

    (function recurse(obj: any, current?: string) {
        if (current && _.isArray(object[current])) {
            // this condition will ignore arrays
            res[current] = object[current];
        } else {
            for (const key in obj) {
                const value = obj[key];
                // joined keys with dot
                const newKey = current ? current + '.' + key : key;
                if (value && typeof value === 'object') {
                    // it's a nested object, so do it again
                    recurse(value, newKey);
                } else {
                    // it's not an object, so set the property
                    res[newKey] = value;
                }
            }
        }
    })(object);

    return res;
}