See this example: https://github.com/facebook/react/issues/11508#issuecomment-345464797.

I think it probably reflects a misunderstanding of how props and state work, and we should detect and warn if we see this.
'boolean value. Make sure to return true or false.',
        getComponentName(ctor) || 'Component',
      );
    }
    return shouldUpdate;
  }
  if (ctor.prototype && ctor.prototype.isPureReactComponent) {
    return (
      !shallowEqual(oldProps, newProps) || !shallowEqual(oldState, newState)
    );
  }
  return true;
}
function checkClassInstance(workInProgress: Fiber, ctor: any, newProps: any) {
  const instance = workInProgress.stateNode;
  if (__DEV__) {
    const name = getComponentName(ctor) || 'Component';
    const renderPresent = instance.render;
    if (!renderPresent) {
      if (ctor.prototype && typeof ctor.prototype.render === 'function') {
        warningWithoutStack(
          false,
          '%s(...): No `render` method found on the returned component ' +
            'instance: did you accidentally return an object from the constructor?',
          name,
        );
      } else {
        warningWithoutStack(
          false,
          '%s(...): No `render` method found on the returned component ' +