reactjs - 类型错误 : Cannot read property 'baseVal' of undefined

Question

我正在使用react-test-renderer的渲染器对我的react组件进行单元测试。它工作正常，但使用 ReactCssTransitionGroup 后，我收到以下错误“TypeError:无法读取未定义的属性'baseVal'”。不知道如何解决这个问题

我确认这个问题是由ReactCssTransitionGroup引起的

下面是我的组件文件:

import React from 'react';
import PropTypes from 'prop-types';
import {List, ListItem, Spinner} from '@stores/reactCommon';
import ReactCSSTransitionGroup from 'react-addons-css-transition-group';

import BagListItem from './bag-list-item';

const BagList = ({bagList, loading}) => {
  const items = bagList.map((item, key) => (
    <ListItem key={key}>
      <BagListItem
        upc={item.upc}
        price={item.sellingPrice}
        description={item.description}
      />
    </ListItem>
  ));
  return (
    <div className="bag-list">
      {loading ? (
        <span className="bag-list__spinner">
          <Spinner size="extra-large" />
        </span>
      ) : null}
      <div className="bag-list__story-default-spacer">
        <List maxHeight="70vh">
          <ReactCSSTransitionGroup
            transitionName="bagList"
            transitionAppear={true}
            transitionAppearTimeout={500}
            transitionEnterTimeout={500}
            transitionLeaveTimeout={300}
          >
            {items}
          </ReactCSSTransitionGroup>
        </List>
      </div>
    </div>
  );
};

BagList.propTypes = {
  bagList: PropTypes.array.isRequired,
  loading: PropTypes.bool
};

export default BagList;

下面是我的单元测试文件

import React from 'react';
import renderer from 'react-test-renderer';
import BagList from '../../../../src/client/js/components/bag-list/bag-list';

describe('<BagList />', function() {
  this.items = [
    {
      upc: '123222123',
      sellingPrice: '12',
      description: 'this is a description'
    },
    {
      upc: '555123',
      price: '23',
      description: 'this is a description'
    }
  ];
  this.getComponent = items => {
    return <BagList bagList={items} loading={false} />;
  };

  it('Should render <BagList /> with bagList', () => {
    // this line is generating the error
    const items = renderer.create(this.getComponent(this.items)).toJSON();
    expect(items).toMatchSnapshot();
  });
});

Answer 1

react-addons-css-transition-group是一个旧包，是 deprecated支持react-transition-group .

react-transition-group 的 v1是一个直接替代品，但在 v2 中被重写。

您可能想要移至 CSSTransition 从最新 react-transition-group .

<小时/>

话虽如此，错误来自于这段代码:

function hasClass(element, className) {
  if (element.classList) return !!className && element.classList.contains(className);else return (" " + (element.className.baseVal || element.className) + " ").indexOf(" " + className + " ") !== -1;
}

...在 hasClass.js模块来自dom-helpers旧包包含 react-addons-css-transition-group .

react-test-renderer ...

...provides an experimental React renderer that can be used to render React components to pure JavaScript objects, without depending on the DOM or a native mobile environment

...所以它没有实现 DOM 提供的所有内容。

在本例中，它看起来像 react-test-renderer没有提供 classList 的实现在element上如此称呼element.className.baseVal抛出您所看到的错误。