Function useSlot

packages/react-aria-components/src/utils.tsx:349–372

(
  initialState: boolean | (() => boolean) = true
)

}

export function useSlot(
  initialState: boolean | (() => boolean) = true
): [RefCallback<Element>, boolean] {
  // Initial state is typically based on the parent having an aria-label or aria-labelledby.
  // If it does, this value should be false so that we don't update the state and cause a rerender when we go through the layoutEffect
  let [hasSlot, setHasSlot] = useState(initialState);
  let hasRun = useRef(false);

  // A callback ref which will run when the slotted element mounts.
  // This should happen before the useLayoutEffect below.
  let ref = useCallback(el => {
    hasRun.current = true;
    setHasSlot(!!el);
  }, []);

  // If the callback hasn't been called, then reset to false.
  useLayoutEffect(() => {
    if (!hasRun.current) {
      setHasSlot(false);
    }
  }, []);

  return [ref, hasSlot];
}

/**
 * Filters out `data-*` attributes to keep them from being passed down and duplicated.