code: def test_returns_empty_list_if_no_documents_are_provided(self):
      sampler = TransformersSimilarityRanker()
      sampler.warm_up()
      output = sampler.run(query="City in Germany", documents=[])
      assert not output["documents"]
  
file_path: haystack/test/components/rankers/test_transformers_similarity.py
imports: from unittest.mock import MagicMock, patch
  import pytest
  import torch
  from transformers.modeling_outputs import SequenceClassifierOutput
  from haystack import Document, ComponentError
  from haystack.components.rankers.transformers_similarity import TransformersSimilarityRanker
label_desc: Use image node_id 9 for calling the TestSimilarityRanker obj's underlying member method code with example usage: obj.test_returns_empty_list_if_no_documents_are_provided() without return types