@Contract(value = "_, null -> false", pure = true)
  private static boolean isInnerClassOf(@Nullable PsiClass inner, @Nullable PsiClass outer) {
    if (inner == null || inner.hasModifierProperty(PsiModifier.STATIC)) return false;
    return PsiTreeUtil.isAncestor(outer, inner, false);
  }
@Contract(value = "_, null -> false", pure = true)
  private static boolean isInnerClassOf(@Nullable PsiClass inner, @Nullable PsiClass outer)