code: def test_run_on_empty_list(self):
      embedder = OpenAIDocumentEmbedder(api_key="fake-api-key")
  
      empty_list_input = []
      result = embedder.run(documents=empty_list_input)
  
      assert result["documents"] is not None
      assert not result["documents"]
  
file_path: haystack/test/components/embedders/test_openai_document_embedder.py
imports: import os
  from typing import List
  import numpy
  import pytest
  from openai import OpenAIError
  from haystack import Document
  from haystack.components.embedders.openai_document_embedder import OpenAIDocumentEmbedder
label_desc: Use image node_id 9 for calling the TestOpenAIDocumentEmbedder obj's underlying member method code with example usage: obj.test_run_on_empty_list() without return types