private boolean isDiamond(@NotNull PsiClassStub<?> stub) {
    if (PsiUtil.isLanguageLevel9OrHigher(this)) {
      String referenceText = stub.getBaseClassReferenceText();
      if (referenceText != null && referenceText.endsWith(">")) {
        return StringUtil.trimEnd(referenceText, ">").trim().endsWith("<");
      }
    }
    return false;
  }
private boolean isDiamond(@NotNull PsiClassStub<?> stub)