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integrations/cohere/src/cohere_haystack/embedders/document_embedder.py

@@ -119,13 +119,17 @@ def run(self, documents: List[Document]):
         :param documents: A list of Documents to embed.
         """
 
-        if not isinstance(documents, list) or not isinstance(documents[0], Document):
+        if not isinstance(documents, list) or documents and not isinstance(documents[0], Document):
             msg = (
                 "CohereDocumentEmbedder expects a list of Documents as input."
                 "In case you want to embed a string, please use the CohereTextEmbedder."
             )
             raise TypeError(msg)
 
+        if not documents:
+            # return early if we were passed an empty list
+            return {"documents": [], "metadata": {}}
+
         texts_to_embed = self._prepare_texts_to_embed(documents)
 
         if self.use_async_client:

integrations/cohere/tests/test_document_embedder.py

@@ -128,10 +128,9 @@ def test_run(self):
     def test_run_wrong_input_format(self):
         embedder = CohereDocumentEmbedder(api_key="test-api-key")
 
-        string_input = "text"
-        list_integers_input = [1, 2, 3]
-
         with pytest.raises(TypeError, match="CohereDocumentEmbedder expects a list of Documents as input"):
-            embedder.run(documents=string_input)
+            embedder.run(documents="text")
         with pytest.raises(TypeError, match="CohereDocumentEmbedder expects a list of Documents as input"):
-            embedder.run(documents=list_integers_input)
+            embedder.run(documents=[1, 2, 3])
+
+        assert embedder.run(documents=[]) == {"documents": [], "metadata": {}}