vant/src/utils/index.ts

import Vue from 'vue';

export { createNamespace } from './create';
export { addUnit } from './format/unit';

export const inBrowser = typeof window !== 'undefined';
export const isServer: boolean = Vue.prototype.$isServer;

// eslint-disable-next-line @typescript-eslint/no-empty-function
export function noop() {}

export function isDef<T>(val: T): val is NonNullable<T> {
  return val !== undefined && val !== null;
}

export function isFunction(val: unknown): val is Function {
  return typeof val === 'function';
}

export function isObject(val: unknown): val is Record<any, any> {
  return val !== null && typeof val === 'object';
}

export function isPromise<T = any>(val: unknown): val is Promise<T> {
  return isObject(val) && isFunction(val.then) && isFunction(val.catch);
}

export function get(object: any, path: string): any {
  const keys = path.split('.');
  let result = object;

  keys.forEach((key) => {
    result = result[key] ?? '';
  });

  return result;
}

/**
 * Checks if `value` is an empty object, collection, map, or set.
 *
 * Objects are considered empty if they have no own enumerable string keyed
 * properties.
 *
 * Array-like values such as `arguments` objects, arrays, buffers, strings, or
 * jQuery-like collections are considered empty if they have a `length` of `0`.
 * Similarly, maps and sets are considered empty if they have a `size` of `0`.
 *
 * @function isEmpty
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is empty, else `false`.
 * @example
 *
 * _.isEmpty(null);
 * // => true
 *
 * _.isEmpty(true);
 * // => true
 *
 * _.isEmpty(1);
 * // => true
 *
 * _.isEmpty([1, 2, 3]);
 * // => false
 *
 * _.isEmpty({ 'a': 1 });
 * // => false
 */
export function isEmpty(value: any): boolean {
  if (value == null) {
    return true;
  }

  if (typeof value !== 'object') {
    return true;
  }

  return Object.keys(value).length === 0;
}