快照测试错误：元素类型无效：应为字符串 [...]

Question

我正在尝试使用 React 和 Jest 进行一些简单的快照测试。

最初我收到此错误：Invariant failed: You should not use <Link> outside a <Router>

阅读this question 后，我更新了我的测试并将我正在测试的组件包装在：<MemoryRouter>...</MemoryRouter>。完成此操作后，我开始收到一个新错误：Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: object. 我不知道这意味着什么。

我的测试：

import React from "react";
import BookTile from "./BookTile";
import MemoryRouter from "react-router-dom";
import renderer from "react-test-renderer";

test("my test", () => {
    let book = {};
    const component = renderer.create(
        <MemoryRouter>
            <BookTile book={book} />
        </MemoryRouter>
    )
    let tree = component.toJSON();
    expect(tree).toMatchSnapshot();
})

我正在测试的组件：

import React from "react";

import {Link} from "react-router-dom";

export default function BookTile(props) {
    return (
        <Link to={`/book/${props.book.id}`}>
            <div className="book-tile" style={{'backgroundImage': `url(${process.env.REACT_APP_API_URL}/uploads/${props.book.cover_image_file_name})`}}>
                <div className='book-tile-title'>
                    {props.book.title}
                </div>
            </div>
        </Link>
    )
}

Answer 1

您没有正确导入内存路由器。它应该是这样的：

import {MemoryRouter} from 'react-router-dom'