Support ForwardRef type of work in TestRenderer

[jquense]

No description provided.

[jquense]

Not sure how to update ShallowRenderer either

[jquense]

i don't understand why the react CI hates me so much

[jquense]

This seems fine in the case where you're rendering just host elements, but maybe not helpful for the HOC case where you wrap and render a single composite component...

[bvaughn]

I think this line should be:

this._rendered = element.type.render(element.props, element.ref);

I'm not sure I understand your PR comment though?

[jquense]

I was thinking of this case:

function withFoo(Component) {
  const Foo = (props) => <Component ref={props.forwardedRef} />
  return React.forwardRef((props, ref) => <Foo forwardedRef={ref} />)
}
shallow(<WithFooComponent><div/></WithFooComponent>)

You'd get a different result than without the forwardRef but I guess that's true of any HoC thing, might even help hide the HoC guts a bit more with is nice.

[bvaughn]

I see. In general, I'm not sure how valuable shallow testing with anything refs or HOC related is. 😄

[bvaughn]

CI is down right now for ReactJS.org repo too:

/bin/bash: yarn: command not found

Looks like this is being caused by an upstream Docker issue, nodejs/docker-node/issues/651

[bvaughn]

I don't think it's possible to have a null React element type?

[jquense]

probably not in practice but the ShallowRenderer tests do <NullIdentifer> which was how i was hitting this.

[bvaughn]

Oh I see. 👍

[bvaughn]

Will this require updates to our release/build script to keep these deps in sync? Needs follow up.

[jquense]

hmm i don't know, I was conflating workspaces and lerna, the latter of which handles the updates

[bvaughn]

These versions are bumped by our release script manually. It's fine. I'll add it to my list of follow up things.

[bvaughn]

Addressed via 610df95

[bvaughn]

Suggestion:

it('should handle ForwardRef', () => {
  const testRef = React.createRef();
  const SomeComponent = React.forwardRef((props, ref) => {
    expect(ref).toEqual(testRef);
    return (
      <div>
        <span className="child1" />
        <span className="child2" />
      </div>
    )
  });

  const shallowRenderer = createRenderer();
  const result = shallowRenderer.render(<SomeComponent ref={testRef} />);

  expect(result.type).toBe('div');
  expect(result.props.children).toEqual([
    <span className="child1" />,
    <span className="child2" />,
  ]);
});

[bvaughn]

I think this line should be:

this._rendered = element.type.render(element.props, element.ref);

I'm not sure I understand your PR comment though?

[bvaughn]

Thanks for this PR, by the way! 😁

[bvaughn]

Lint, Flow, and tests pass for me locally so I'm going to move forward in spite of the CI/Docker issue.