Question

我用玩笑框架测试传奇。当我引发新的错误时，我想测试代码，但是我遇到了问题。

传奇功能

  try {
    const clientId = yield select(selectClientId)

    if (!clientId) {
      throw new Error('Client id is not exists')
    }
    const response = yield call(fetcher, {options})
    yield put(clientReceiveData({ data: response }))
  } catch (err) {
    yield put(clientRequestDataFailure())
  }
}

这是一个测试传奇

describe('client fetch data', () => {
  const gen = cloneableGenerator(clientDataFetch)(params)
  expect(gen.next().value).toEqual(select(selectClientId))

  // @ts-ignore
  expect(gen.throw(new Error('Client id is not exists')).value).toEqual( put(clientRequestDataFailure()))

  // Here expect(received) is undefined
  expect(gen.next().value).toEqual(call(fetcher, {options}))
})

未收到与调用提取程序相等的信息

Answer 1

您已经完成了生成器?，不再需要执行任何代码，断言的方式是：：

expect(gen.next()).toStrictEqual({ done: true, value: undefined })

但是，对于整洁的代码，您要做要预见未定义客户端ID的情况，并且已经正确处理了该情况，因此这不是意外的异常，请尝试：

// generator.ts
function* clientDataFetch(params) {
    //...

    const clientId = yield select(selectClientId)

    if (!clientId) {
        yield put(clientRequestDataFailure())
    } else {
        const response = yield call(fetcher, {options})
        yield put(clientReceiveData({ data: response }))
    }
}

// test.ts

describe('client fetch data', () => {
  const gen = cloneableGenerator(clientDataFetch)(params)
  expect(gen.next().value).toEqual(select(selectClientId))

  // just return the falsy value
  expect(gen.next(undefined).value).toEqual(put(clientRequestDataFailure()))
  expect(gen.next()).toStrictEqual({ done: true, value: undefined })
})

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1 个答案: