private static Icon getIconInternal(@NotNull PsiDirectory directory) {
      ProjectFileIndex fileIndex = ProjectRootManager.getInstance(directory.getProject()).getFileIndex();
      VirtualFile virtualFile = directory.getVirtualFile();
      if (fileIndex.isInTestSourceContent(virtualFile)) {
        return PlatformIcons.MODULES_TEST_SOURCE_FOLDER;
      }
      else if (fileIndex.isInSourceContent(virtualFile)) {
        return PlatformIcons.MODULES_SOURCE_FOLDERS_ICON;
      }
      else {
        return PlatformIcons.FOLDER_ICON;
      }
    }
private static Icon getIconInternal(@NotNull PsiDirectory directory)