使用useSelector时,Reaction测试库无法工作 [英] React Testing Library cannot work when I use useSelector
本文介绍了使用useSelector时,Reaction测试库无法工作的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
useSelector
组件,当我想测试呈现文本时,它在useSelector
上显示错误消息,并显示错误消息:could not find react-redux context value; please ensure the component is wrapped in a <Provider>
。我已经把<Provider>
放到了顶层组件,我的测试代码哪里错了?应用本身运行正常。
顶级组件:
import React from "react"
import ReactDOM from "react-dom"
import App from "./App"
import { Provider } from "react-redux"
import store from "./redux/store"
ReactDOM.render(
<Provider store={store}>
<App />
</Provider>,
document.getElementById("test")
)
App.js
import { useEffect, useState, useCallback } from "react"
import { useDispatch, useSelector } from "react-redux"
import { fetchPosts, showName } from "./redux/actions/posts"
import Main from "./component/main"
function App() {
const { posts, name } = useSelector((state) => state.posts)
const dispatch = useDispatch()
const handleClick = useCallback(() => {
dispatch(fetchPosts())
}, [])
const handleShowName = useCallback((textName) => {
dispatch(showName(textName))
}, [])
return (
<div className="App" data-test="appComponent">
<button onClick={handleClick}>get post</button>
<button onClick={() => handleShowName("test")}>Show name</button>
<section className="main">
<div>project name: {name}</div>
<Main posts={posts} />
</section>
</div>
)
}
export default App
app.est.js
import React from "react"
import App from "./App"
import { render, fireEvent, screen } from "@testing-library/react"
it("render a div with text 'project name'", () => {
const { container, getByText } = render(<App />)
expect(getByText("project name:")).toBeInTheDocument()
})
当我测试我的Redux操作和Redux Reducer时,我的测试正在工作。因此,Jest
设置应该可以。
jest.config.js
module.exports = {
setupFilesAfterEnv: ["./setupTests.js"]
}
setupTest.js
import '@testing-library/jest-dom/extend-expect';
Babel.config.js
module.exports = {
presets: ["@babel/preset-env", "@babel/preset-react"],
plugins: [
["@babel/plugin-proposal-class-properties", { loose: false }],
[
"@babel/plugin-transform-runtime",
{
corejs: 3,
helpers: true,
regenerator: true
}
]
]
}
推荐答案
您需要为正在测试的组件提供还原上下文(隔离)。
最低限度是创建一个简单的wrapper component(另请参阅custom render),类似于应用程序中的提供程序,传入render
测试实用程序的选项。
import { Provider } from "react-redux"
import store from "./redux/store"
const ReduxWrapper = ({ children }) => (
<Provider store={store}>
{children}
</Provider>
);
it("render a div with text 'project name'", () => {
const { container, getByText } = render(
<App />,
{ wrapper: ReduxWrapper },
);
expect(getByText("project name:")).toBeInTheDocument()
});
请参阅Redux文档进行测试connected components。
要点是创建包括还原存储的自定义呈现函数。
import React from 'react';
import { render as rtlRender } from '@testing-library/react';
import { createStore } from 'redux';
import { Provider } from 'react-redux';
// Import your own reducer
import store from "./redux/store";
function render(
ui,
{
initialState,
store = createStore(reducer, initialState),
...renderOptions
} = {}
) {
function Wrapper({ children }) {
return <Provider store={store}>{children}</Provider>
}
return rtlRender(ui, { wrapper: Wrapper, ...renderOptions });
}
// re-export everything
export * from '@testing-library/react';
// override render method
export { render };
然后为测试导入自定义render
实用程序
import { render, fireEvent, screen } from "../testUtils";
it("render a div with text 'project name'", () => {
const { container, getByText } = render(
<App />,
// pass any options here like initial state, custom store, etc...
);
expect(getByText("project name:")).toBeInTheDocument();
});
这篇关于使用useSelector时,Reaction测试库无法工作的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
查看全文