Check for children of fragments in childrenOfType validator

[knowler]

I have a component with a sub-component API and I want to validate that the children of the component are a part of that sub-component API. The childrenOfType validator lets me do this (thanks!), but I have discovered an edge case that could be solved with slight modification to the existing validator. The edge case is when a fragment is used to wrap the children. For example, consider the following sub-component API + component prop-types spec:

// Sub-component API
Component.A = A;
Component.B = B;

Component.propTypes = {
  children: childrenOfType(Component.A, Component.B),
};

Now, if I am conditionally rendering the children of the component and a case where multiple child elements are the resulting expression I need to wrap those with a fragment so that it is valid JSX. This causes childrenOfType to err.

<Component>
  {someCondition ? (
    <>
      <Component.A>Some content</Component.A>
      <Component.B>Some more content</Component.B>
    </> 
  ) : (
    <Component.A>
      Some other content
    </Component.A>
  )}
</Component>

I do realize that the above could be solved by writing the conditional differently, however, I do think that it seems reasonable for the childrenOfType validator to recognize a fragment as a non-element and to forward its checking of the children to the fragment. Thoughts?

[ljharb]

That does seem reasonable to me, since a fragment should be equivalent to an array of children. Want to make a PR?