Jest snapshot testing error: You should not use <Link> outside a <Router>

问题

I want to write snapshot test for my Footer component, but it throws error: You should not use <Link> outside a <Router>. Here is my code:

import React from 'react'
import renderer from 'react-test-renderer'

import Footer from '../footer'

it('Footer renders correctly', () => {
    const tree = renderer
        .create(<Footer />)
        .toJSON()

    expect(tree).toMatchSnapshot()
})

I know this happens because Footer component uses Link from react-router-dom. In order to solve this problem I wrapped Footer component in BrowserRouter:

const tree = renderer
    .create(
        <BrowserRouter>
            <Footer />
        </BrowserRouter>
    )
    .toJSON()

but now it throws error: Browser history needs a DOM

回答1:

I used MemoryRouter instead of BrowserRouter and it solved the problem.

import React from 'react'
import { MemoryRouter } from 'react-router-dom'
import renderer from 'react-test-renderer'

import Footer from '../footer'

it('Footer renders correctly', () => {
const tree = renderer
    .create(
        <MemoryRouter>
            <Footer />
        </MemoryRouter>
    )
    .toJSON()

    expect(tree).toMatchSnapshot()
})

来源：https://stackoverflow.com/questions/55791828/jest-snapshot-testing-error-you-should-not-use-link-outside-a-router