React Native：'Jest did not exit one second after the test run has completed' with @testing-library/react-hooks 和 react-query

Question

我正在使用 jest 和 @testing-library/react-hooks 来测试在我的 React Native 代码中使用 react-query 实现的挂钩。

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')

  })

})

我在 each/all 之前尝试使用 cleanup、done、unmount 等，但没有结果。如果我从 useSomething 中删除 useQuery，问题就会消失。

知道如何解决吗？

Answer 1

您可以尝试定义一个函数，例如：

export function flushPromises() {
  return new Promise((resolve) => setImmediate(resolve));
}

那么在你考试前 expect:

await flushPromises();

更多信息

Answer 2

过去曾在此处报告过此问题： https://github.com/tannerlinsley/react-query/issues/1847

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

每次测试后清除 queryCache： afterEach(() => { queryClient.clear() });
将 cacheTime 设置为 0 以进行测试，例如与：queryClient.setDefaultOptions({ queries: { cacheTime: 0 } })
使用jest.useFakeTimers()

React Native：'Jest did not exit one second after the test run has completed' with @testing-library/react-hooks 和 react-query

React Native: 'Jest did not exit one second after the test run has completed' with @testing-library/react-hooks and react-query

react-native

react-hooks

jestjs

react-query

testing-library