正如说的那样，当您在除1以外的任意数量的节点上运行该错误时，就会发生该错误。
与jQuery类似，您的find调用将返回一定数量的节点（实际上，这是一个包装器，它知道find选择器找到了多少个节点）。而且您不能调用simulate0个节点！或多个。
然后的解决方案是弄清楚选择器（styles.containerinwrapper.find(styles.container)）为什么返回0个节点，并确保它恰好返回1，然后simulate将按预期工作。
const container = wrapper.find(styles.container)expect(container.length).to.equal(1)container.simulate(’keyup’, {keyCode: 27});expect(store.getActions()[0]).to.deep.equal(expectedAction);
酶的调试方法在这里非常有用。您可以这样做console.log(container.debug())，或者也console.log(container.html())可以确保您的组件在测试过程中按预期方式呈现。
解决方法我正在测试组件中的键绑定功能。该组件非常简单，事件监听器用于keyup并触发一个 redux操作 ，该 操作 将隐藏该组件。
我已经在这里将代码清理为仅包含相关信息。如果仅使用 商店分派进行操作调用，我就能通过测试，但是这样做当然会破坏测试的目的。我正在使用酶keyup用适当的事件数据（的键代码esc）模拟事件，但遇到以下错误。
MyComponent.js
import React,{Component,PropTypes} from ’react’;import styles from ’./LoginForm.scss’;import {hideComponent} from ’../../actions’;import {connect} from ’react-redux’;class MyComponent extends Component { static propTypes = { // props }; componentDidMount() { window.addEventListener(’keyup’,this.keybindingClose); } componentWillUnmount() { window.removeEventListener(’keyup’,this.keybindingClose); } keybindingClose = (e) => { if (e.keyCode === 27) { this.toggleView(); } }; toggleView = () => { this.props.dispatch(hideComponent()); }; render() { return ( <div className={styles.container}>// render code </div> ); }}export default connect(state => ({ // code}))(MyComponent);
MyComponent-test.js
import React from ’react’;import chai,{expect} from ’chai’;import chaiEnzyme from ’chai-enzyme’;import configureStore from ’redux-mock-store’;import {mount} from ’enzyme’;import {Provider} from ’react-redux’;import thunk from ’redux-thunk’;import {MyComponent} from ’../../common/components’;import styles from ’../../common/components/MyComponent/MyComponent.scss’;const mockStore = configureStore([thunk]);let store;chai.use(chaiEnzyme());describe.only(’<MyComponent/>’,() => { beforeEach(() => { store = mockStore({}); }); afterEach(() => { store.clearActions(); }); it(’when esc is pressed HIDE_COMPONENT action reducer is returned’,() => { const props = { // required props for MyComponent }; const expectedAction = { type: require(’../../common/constants/action-types’).HIDE_COMPONENT }; const wrapper = mount( <Provider store={store} key='provider'><LoginForm {...props}/> </Provider> ); // the dispatch function below will make the test pass but of course it is not testing the keybinding as I wish to do so // store.dispatch(require(’../../common/actions’).hideComponent()); wrapper.find(styles.container).simulate(’keyup’,{keyCode: 27}); expect(store.getActions()[0]).to.deep.equal(expectedAction); });});
错误：
Error: This method is only meant to be run on single node. 0 found instead.at ReactWrapper.single (/Users/[name]/repos/[repoName]/webpack/test.config.js:5454:18 <- webpack:///~/enzyme/build/ReactWrapper.js:1099:0)at ReactWrapper.simulate (/Users/[name]/repos/[repoName]/webpack/test.config.js:4886:15 <- webpack:///~/enzyme/build/ReactWrapper.js:531:0)at Context.<anonymous> (/Users/[name]/repos/[repoName]/webpack/test.config.js:162808:55 <- webpack:///src/test/components/MyComponent-test.js:39:40)
