private static boolean groupReferenceByCodeBlocks(Map<PsiCodeBlock, Collection<PsiReferenceExpression>> refs, PsiReferenceExpression psiReference) {
    final PsiCodeBlock block = getTopmostBlock(psiReference);
    if (block == null) {
      return false;
    }

    Collection<PsiReferenceExpression> references = refs.get(block);
    if (references == null) {
      references = new ArrayList<>();
      if (findExistentBlock(refs, psiReference, block, references)) return true;
      refs.put(block, references);
    }
    references.add(psiReference);
    return true;
  }
private static boolean groupReferenceByCodeBlocks(Map<PsiCodeBlock, Collection<PsiReferenceExpression>> refs, PsiReferenceExpression psiReference)