discriminated union as props

type SidebareOpenContentsProps = {
  showSkeletons: boolean;
  sidebarItems: MockSidebarItems | {};
} & (
  | {
      showSkeletons: true;
      sidebarItems: {};
    }
  | {
      showSkeletons: false;
      sidebarItems: MockSidebarItems;
    }
);

        <SidebarOpenContents
          sidebarItems={status === "success" ? sidebarItems : {}}
          showSkeletons={status === "loading"}
        />