用玩笑测试中继[createFragmentContainer]？

Question

I am tring to test my components but every component that exports createFragmentContainer shows me this issue:

console.error node_modules\react-native\Libraries\Core\ExceptionsManager.js:73
      Warning: Failed context type: Invalid prop/context `relay` supplied to `Relay(Product)`, expected `undefined` to be an object with an `environment` and `variables`.
          in Relay(Product)
    console.error node_modules\react-native\Libraries\Core\ExceptionsManager.js:73
      React caught an error thrown by Relay(Product). You should fix this error in your code. Consider adding an error boundary to your tree to customize error handling behavior.

      TypeError: Cannot read property 'environment' of undefined

      The error is located at:
          in Relay(Product)

so does jest support fragment containers or the problem is in my project ?

Answer 1

Add the below to __mocks__ folder. Then in the test add jest.mock('react-relay'); to the unit test that needs relay.

 import React from 'react'; import PropTypes from 'prop-types'; const relayMock = jest.genMockFromModule('react-relay'); const relayChildContextTypes = { relay: PropTypes.object, }; const relayEnvironment = { lookup: jest.fn(), }; const relayContext = { relay: { environment: relayEnvironment, variables: {}, }, }; const relayFragmentProps = { relay: { environment: relayEnvironment, }, }; const relayRefetchProps = { relay: { environment: relayEnvironment, refetch: jest.fn(), }, }; const relayPaginationProps = { relay: { environment: relayEnvironment, hasMore: jest.fn(), loadMore: jest.fn(), isLoading: jest.fn(), }, }; relayMock.__relayEnvironment = relayEnvironment; relayMock.__relayFragmentProps = relayFragmentProps; relayMock.__relayRefetchProps = relayRefetchProps; relayMock.__relayPaginationProps = relayPaginationProps; const makeRelayWrapper = (relayProps) => ( (Comp) => { class HOC extends React.Component { getChildContext() { return relayContext; } render() { return <Comp {...this.props} {...relayProps}/>; } } HOC.childContextTypes = relayChildContextTypes; return HOC; } ); relayMock.QueryRenderer = jest.fn(() => React.createElement('div', null, 'Test')); relayMock.createFragmentContainer = makeRelayWrapper(relayFragmentProps); relayMock.createRefetchContainer = makeRelayWrapper(relayRefetchProps); relayMock.createPaginationContainer = makeRelayWrapper(relayPaginationProps); module.exports = relayMock;