public static @Nullable VirtualFile findRelativeFile(@Nullable VirtualFile base, String @NotNull ... path) {
    VirtualFile file = base;

    for (String pathElement : path) {
      if (file == null) return null;
      if ("..".equals(pathElement)) {
        file = file.getParent();
      }
      else {
        file = file.findChild(pathElement);
      }
    }

    return file;
  }
public static @Nullable VirtualFile findRelativeFile(@Nullable VirtualFile base, String @NotNull ... path)