Function isPrevSelected

packages/@react-spectrum/s2/src/TreeView.tsx:845–851

(id: Key | undefined, state: TreeState<unknown>)

}

function isPrevSelected(id: Key | undefined, state: TreeState<unknown>) {
  if (id == null || !state) {
    return false;
  }
  let keyBefore = state.collection.getKeyBefore(id);
  return keyBefore != null && state.selectionManager.isSelected(keyBefore);
}

function isFirstItem(id: Key | undefined, state: TreeState<unknown>) {
  if (id == null || !state) {