element-ui/test/unit/util.js

import Vue from 'vue/dist/vue';
import Element from 'main/index.js';

Vue.use(Element);

let id = 0;

const createElm = function() {
  const elm = document.createElement('div');

  elm.id = 'app' + ++id;
  document.body.appendChild(elm);

  return elm;
};

/**
 * 创建一个 Vue 的实例对象
 * @param  {Object|String}  Compo   组件配置，可直接传 template
 * @param  {Boolean=false} mounted 是否添加到 DOM 上
 * @return {Object} vm
 */
exports.createVue = function(Compo, mounted = false) {
  const elm = createElm();

  if (Object.prototype.toString.call(Compo) === '[object String]') {
    Compo = { template: Compo };
  }
  return new Vue(Compo).$mount(mounted === false ? null : elm);
};

/**
 * 创建一个测试组件实例
 * @link http://vuejs.org/guide/unit-testing.html#Writing-Testable-Components
 * @param  {Object}  Compo          - 组件对象
 * @param  {Object}  propsData      - props 数据
 * @param  {Boolean=false} mounted  - 是否添加到 DOM 上
 * @return {Object} vm
 */
exports.createTest = function(Compo, propsData = {}, mounted = false) {
  if (propsData === true || propsData === false) {
    mounted = propsData;
    propsData = {};
  }
  const elm = createElm();
  const Ctor = Vue.extend(Compo);
  return new Ctor({ propsData }).$mount(mounted === false ? null : elm);
};

/**
 * 触发一个事件
 * mouseenter, mouseleave, mouseover 等
 * @param  {Element} elm
 * @param  {EventName} name
 * @param  {options} opts
 */
exports.triggerEvent = function(elm, name, opts) {
  const evt = document.createEvent('MouseEvents');

  evt.initEvent(name, ...opts);
  elm.dispatchEvent
    ? elm.dispatchEvent(evt)
    : elm.fireEvent('on' + name, evt);
};