code: def test_run(self):
      embedder = SentenceTransformersDocumentEmbedder(model="model")
      embedder.embedding_backend = MagicMock()
      embedder.embedding_backend.embed = (
          lambda x, **kwargs: np.random.rand(len(x), 16).tolist()
      )
  
      documents = [
          Document(content=f"document number {i}") for i in range(5)
      ]
  
      result = embedder.run(documents=documents)
  
      assert isinstance(result["documents"], list)
      assert len(result["documents"]) == len(documents)
      for doc in result["documents"]:
          assert isinstance(doc, Document)
          assert isinstance(doc.embedding, list)
          assert isinstance(doc.embedding[0], float)
  
file_path: haystack/test/components/embedders/test_sentence_transformers_document_embedder.py
imports: from unittest.mock import patch, MagicMock
  import pytest
  import numpy
  from haystack import Document
  from haystack.components.embedders.sentence_transformers_document_embedder import SentenceTransformersDocumentEmbedder
label_desc: Use image node_id 7 for calling the TestSentenceTransformersDocumentEmbedder obj's underlying member method code with example usage: obj.test_run() without return types