private static boolean isDummy(ModuleSourceSet set, ModulesProvider modulesProvider) {
    JavaSourceRootType type = set.getType().isTest()? JavaSourceRootType.TEST_SOURCE : JavaSourceRootType.SOURCE;
    ModuleRootModel rootModel = modulesProvider.getRootModel(set.getModule());
    for (ContentEntry entry : rootModel.getContentEntries()) {
      if (!entry.getSourceFolders(type).isEmpty()) {
        return false;
      }
    }
    return true;
  }
private static boolean isDummy(ModuleSourceSet set, ModulesProvider modulesProvider)