React Native：使用@testing-library/react-hooks和react-query“测试运行完成后一秒Jest没有退出”

Question

我正在使用jest并@testing-library/react-hooks测试react-query在我的 React Native 代码中实现的钩子。

测试工作正常，但最后我得到：

Jest did not exit one second after the test run has completed.

This usually means that there are asynchronous operations that weren't stopped in your tests. Consider running Jest with `--detectOpenHandles` to troubleshoot this issue.

这是我的简化代码：

import { renderHook } from '@testing-library/react-hooks'
import React from 'react'
import { QueryClient, QueryClientProvider, useQuery } from 'react-query'

const useSomething = () => {
  return useQuery('myquery', () => 'OK')
}

beforeAll((done) => {
  done()
})

afterAll((done) => {
  done()
})

// test cases
describe('Testing something', () => {
  it('should do something', async () => {
    const queryClient = new QueryClient()
    const wrapper = ({ children }: { children: React.ReactFragment }) => (
      <QueryClientProvider client={queryClient}>{children}</QueryClientProvider>
    )
    const { result, waitFor } = renderHook(() => useSomething(), { wrapper })

    await waitFor(() => {
      return result.current.isSuccess
    })

    expect(result.current.data).toBe('OK')

  })

})

我尝试在每个/全部之前使用cleanup、done、unmount等，但没有结果。如果我useQuery从 中删除useSomething，问题就会消失。

知道如何修复它吗？

Answer 1

这个问题过去曾在这里报告过： https://github.com/tannerlinsley/react-query/issues/1847

该问题是由 React-query 垃圾收集计时器运行引起的，默认为 5 分钟。正如问题中所述，解决方案是：

• 每次测试后清除queryCache： afterEach(() => { queryClient.clear() });
• 设置cacheTime为0您的测试，例如：queryClient.setDefaultOptions({ queries: { cacheTime: 0 } })
• 使用jest.useFakeTimers()