Is CreateNodeMock supported?

Is CreateNodeMock supported?

I am not sure if I am using this wrong, but I am trying to mock a ref method. According to the API for the render function, it states:

function render(
  component: React.Element<any>,
  options?: {
    /* A React Component that renders `component` as children */
    wrapper?: React.ComponentType<any>,
    /* You won't often use this, but it's helpful when testing refs */
    createNodeMock: (element: React.Element<any>) => any,
  }
): RenderResult {}

I am passing in the options like so (which I got from react-test-renderer)

const options = {
   createNodeMock: (element) => {
      console.log("element", element);
      return {
         takePictureAsync: takePictureMock
       };
    }
};

const {getByType, queryByTestId} = render(<Camera/>, options);

I never see the console.log print anything and I cannot find a test in render.test.js that covers the use of CreateNodeMock.

[almeynman]

For those who will encounter this problem in the future.

Worked around it by

1. Introduce a useRef optional prop and by default use react’s one

import React, { useRef as defaultUseRef } from 'react'
const component = ({ useRef = defaultUseRef }) => {
  const ref = useRef(null)
  return <RefComponent ref={ref} />
}

1. in test mock useRef

const mockUseRef = (obj: any) => () => Object.defineProperty({}, 'current', {
  get: () => obj,
  set: () => {}
})

// in your test
...
    const useRef = mockUseRef({ refFunction: jest.fn() })
    render(
      <ScanBarcodeView onScan={handleScan} useRef={useRef} />,
    )
...

[thymikee]

We pass it to react-test-renderer, but it doesn’t seem to work with react-native, at least the last time I tried to use it. Didn’t dig it too much though. We’d be glad if you helped us get it working 😃