如何编写catch块的测试用例以覆盖redux-saga的100％代码行

Question

我正在使用redux-saga来按如下方式获取api：

// getTodoListSaga.js
import { call, put, takeLatest } from 'redux-saga/effects'
import { create } from  'apisauce'

export const API = create({
  baseURL: `http://localhost:4000`,
  headers: {
    'Content-Type': 'application/json'
  }
})


function* getTodoList() {
  try {
    const response = yield call(() => API.get(`/todos`))

    if (response.ok) {
      yield put({
        type: 'GET_TODOS_SUCCESS',
        data: response.data
      })
    } else {
      yield put({
        type: 'GET_TODOS_FAILED'
      })
    }
  } catch (errors) {
    yield put({
      type: 'GET_TODOS_FAILED'
    })
  }
}

function* getTodoListSaga() {
  yield takeLatest('GET_TODOS_REQUEST', getTodoList)
}

export default getTodoListSaga

我尝试应用redux-saga-test-plan对其进行如下测试：

// __tests__/getTodoListSaga.test.js
import { call } from 'redux-saga/effects'
import MockAdapter from 'axios-mock-adapter'
import { expectSaga } from 'redux-saga-test-plan'
import getTodoListSaga, { API } from '../getTodoListSaga'

const API_URL = 'http://localhost:4000'

describe('getTodoList saga test', () => {

  it('Test fetch Todos success', () => {
    const todos = [
      { id: 1, todo: 'Go shopping' },
      { id: 2, todo: 'Go Camping' }
    ]

    const mock = new MockAdapter(API.axiosInstance)
    mock.onGet(`${API_URL}/todos`).reply(200, todos)
    const getTodos = () => API.get(`${API_URL}/todos`)

    return expectSaga(getTodoListSaga)
      .provide([[call(() => getTodos), { response: { ok: true, data: todos }}]])
      .put({ type: 'GET_TODOS_SUCCESS', data: todos })
      .dispatch({ type: 'GET_TODOS_REQUEST' })
      .silentRun()
  })

  it('Test fetch Todos fail', () => {
    const error = 404
    const mock = new MockAdapter(API.axiosInstance)
    mock.onGet(`${API_URL}/todos`).reply(error)
    const getTodos = () => API.get(`${API_URL}/todos`)

    return expectSaga(getTodoListSaga)
      .provide([[call(() => getTodos), error]])
      .put({ type: 'GET_TODOS_FAILED' })
      .dispatch({ type: 'GET_TODOS_REQUEST' })
      .silentRun()
  })
})

但是我不知道如何测试catch块以覆盖100％的代码行。有人帮我吗？