Question

测试public virtual Cat Cat钩子，我发现有点困难，因为该方法已被省略/未记录在Apollo docs上（在撰写本文时）。大概应该使用useSubscription中的<MockedProvider />来模拟它，就像该链接中给出的示例中的突变一样。

测试我正在工作的订阅的加载状态：

组件：

@apollo/react-testing

并成功测试了订阅的加载状态：

const GET_RUNNING_DATA_SUBSCRIPTION = gql`
  subscription OnLastPowerUpdate {
    onLastPowerUpdate {
      result1,
      result2,
    }
  }
`;

const Dashboard: React.FC<RouteComponentProps & Props> = props => {
  const userHasProduct = !!props.user.serialNumber;

  const [startGetRunningData] = useMutation(START_GET_RUNNING_DATA);

  const [stopGetRunningData] = useMutation(STOP_GET_RUNNING_DATA);

  useEffect(() => {
    startGetRunningData({
      variables: { serialNumber: props.user.serialNumber },
    });

    return () => {
      stopGetRunningData();
    };
  }, [startGetRunningData, stopGetRunningData, props]);

  const SubscriptionData = (): any => {
    const { data, loading } = useSubscription(GET_RUNNING_DATA_SUBSCRIPTION);

    if (loading) {
      return <Heading>Data loading...</Heading>;
    }

    const metrics = [];
    if (data) {
      console.log('DATA NEVER CALLED IN TEST!');
    }

    return metrics;
  };

  if (!userHasProduct) {
    return <Redirect to="/enter-serial" />;
  }

  return (
    <>
      <Header />
      <PageContainer size="midi">
        <Panel>
          <SubscriptionData />
        </Panel>
      </PageContainer>
    </>
  );
};

根据最后一个示例from the docs上用于测试useMutation的说明，添加另一个测试以等待从传入的模拟中解析出数据为止，您必须等待它。

测试通过：

import React from 'react';
import thunk from 'redux-thunk';
import { createMemoryHistory } from 'history';
import { create } from 'react-test-renderer';
import { Router } from 'react-router-dom';
import wait from 'waait';
import { MockedProvider } from '@apollo/react-testing';
import { Provider } from 'react-redux';

import configureMockStore from 'redux-mock-store';

import Dashboard from './Dashboard';

import {
  START_GET_RUNNING_DATA,
  STOP_GET_RUNNING_DATA,
  GET_RUNNING_DATA_SUBSCRIPTION,
} from './queries';

const mockStore = configureMockStore([thunk]);

const serialNumber = 'AL3286wefnnsf';

describe('Dashboard page', () => {
  let store: any;

  const fakeHistory = createMemoryHistory();

  const mocks = [
    {
      request: {
        query: START_GET_RUNNING_DATA,
        variables: {
          serialNumber,
        },
      },
      result: {
        data: {
          startFetchingRunningData: {
            startedFetch: true,
          },
        },
      },
    },
    {
      request: {
        query: GET_RUNNING_DATA_SUBSCRIPTION,
      },
      result: {
        data: {
          onLastPowerUpdate: {
            result1: 'string',
            result2: 'string'
          },
        },
      },
    },
    {
      request: {
        query: STOP_GET_RUNNING_DATA,
      },
      result: {
        data: {
          startFetchingRunningData: {
            startedFetch: false,
          },
        },
      },
    },
  ];

  afterEach(() => {
    jest.resetAllMocks();
  });

  describe('when initialising', () => {
    beforeEach(() => {
      store = mockStore({
        user: {
          serialNumber,
          token: 'some.token.yeah',
          hydrated: true,
        },
      });
      store.dispatch = jest.fn();
    });

    it('should show a loading state', async () => {
      const component = create(
        <Provider store={store}>
          <MockedProvider mocks={mocks} addTypename={false}>
            <Router history={fakeHistory}>
              <Dashboard />
            </Router>
          </MockedProvider>
        </Provider>,
      );

      expect(component.root.findAllByType(Heading)[0].props.children).toBe(
        'Data loading...',
      );
    });
  });
});

错误的测试抛出错误：

it('should run the data', async () => {
      const component = create(
        <Provider store={store}>
          <MockedProvider mocks={mocks} addTypename={false}>
            <Router history={fakeHistory}>
              <Dashboard />
            </Router>
          </MockedProvider>
        </Provider>,
      );
      await wait(0);
    });

依赖项：

No more mocked responses for the query: subscription OnLastPowerUpdate {

我已经尝试过的事情：

反应测试渲染器/酶/ @ testing-library / react
awaiting next tick
initialising the client在测试中有所不同

Github存储库，例如：

https://github.com/harrylincoln/apollo-subs-testing-issue

有人在那里可以提供帮助吗？

Answer 1

我在这里看到的问题是，您在SubscriptionData组件内声明了Dashboard组件，因此，下次重新渲染Dashboard组件时，另一个{{1 }}组件将创建，您将看到错误消息：

该查询不再有模拟响应：订阅OnLastPowerUpdate

我建议您从SubscriptionData组件中取出SubscriptionData组件，这样就只能创建一次

Dashboard

对于测试，您可以尝试执行以下操作：

const SubscriptionData = (): any => {
  const { data, loading } = useSubscription(GET_RUNNING_DATA_SUBSCRIPTION);

  if (loading) {
    return <Heading>Data loading...</Heading>;
  }

  const metrics = [];
  if (data) {
    console.log('DATA NEVER CALLED IN TEST!');
  }

  return metrics;
};

const Dashboard: React.FC<RouteComponentProps & Props> = props => {
  const userHasProduct = !!props.user.serialNumber;

  const [startGetRunningData] = useMutation(START_GET_RUNNING_DATA);

  const [stopGetRunningData] = useMutation(STOP_GET_RUNNING_DATA);

  useEffect(() => {
    startGetRunningData({
      variables: { serialNumber: props.user.serialNumber },
    });

    return () => {
      stopGetRunningData();
    };
  }, [startGetRunningData, stopGetRunningData, props]);

  if (!userHasProduct) {
    return <Redirect to="/enter-serial" />;
  }

  return (
    <>
      <Header />
      <PageContainer size="midi">
        <Panel>
          <SubscriptionData />
        </Panel>
      </PageContainer>
    </>
  );
};

测试使用订阅带有反应的阿波罗钩子

1 个答案: