isRenderFunction.ts

// See discussion:
// https://discuss.reactjs.org/t/how-to-determine-if-js-object-is-react-component/2825/2
import { ReactComponentOrRenderFunction, RenderFunction } from "./types/index";

/**
 * Used to determine we'll call be calling React.createElement on the component of if this is a
 * Render-Function used return a function that takes props to return a React element
 * @param component
 * @returns {boolean}
 */
export default function isRenderFunction(component: ReactComponentOrRenderFunction): boolean {
  // No for es5 or es6 React Component
  if (
    (component as RenderFunction).prototype &&
    (component as RenderFunction).prototype.isReactComponent) {
    return false;
  }

  if ((component as RenderFunction).renderFunction) {
    return true;
  }

  // If zero or one args, then we know that this is a regular function that will
  // return a React component
  if (component.length >= 2) {
    return true;
  }

  return false;
}