如何编写saga测试用例

Question

我在saga中有以下方法

export function* loadCustomerDetails(action) {
  const customer = yield call(() => educationAPI.fetchCustomerDetails(action.id));
  yield put(saveCustomerDetails(customer));
}

function* watchLoadCustomereDetails() {
  yield takeLatest(actionTypes.LOAD_CUSTOMER_DETAILS, loadCustomerDetails);
}

export default function* root() {
  yield fork(watchLoadCustomerDetails);
}

我写了以下测试用例

describe('loadCustomerDetails', () => {
  const generator = cloneableGenerator(loadCustomerDetails)();
  const customerDetails = {
    items: undefined,
  };

  it('does nothing with no data', () => {
    const clone = generator.clone();
    expect(clone.next().value).toEqual(call(educationAPI.fetchCustomerDetails));
    expect(clone.next(customerDetails).value).toEqual(put(saveCustomerDetails()));
    expect(clone.next().done).toBe(true);
  });
});

当我运行我的测试用例时，我收到错误：

Expected value to equal:
      {"@@redux-saga/IO": true, "PUT": {"action": {"customerDetails": undefined, "type": "SAVE_CUSTOMER_DETAILS"}, "channel": null}}
    Received:
      {"@@redux-saga/IO": true, "CALL": {"args": [], "context": null, "fn": [Function anonymous]}}

为什么我的测试用例失败了？