fix: move imports to top level, use async callback in async test

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ArkaD171717

integrations/mistral/tests/test_mistral_chat_generator.py

@@ -1185,24 +1185,26 @@ def test_run_empty_messages(self, monkeypatch):
         assert response == {"replies": []}
 
     def test_convert_response_from_json_string(self):
-        json_str = json.dumps({
-            "id": "test",
-            "model": "mistral-small-latest",
-            "choices": [
-                {
-                    "finish_reason": "stop",
-                    "index": 0,
-                    "message": {
-                        "role": "assistant",
-                        "content": [
-                            {"type": "thinking", "thinking": [{"type": "text", "text": "Thinking."}]},
-                            {"type": "text", "text": "Answer."},
-                        ],
-                    },
-                }
-            ],
-            "usage": {"prompt_tokens": 5, "completion_tokens": 10, "total_tokens": 15},
-        })
+        json_str = json.dumps(
+            {
+                "id": "test",
+                "model": "mistral-small-latest",
+                "choices": [
+                    {
+                        "finish_reason": "stop",
+                        "index": 0,
+                        "message": {
+                            "role": "assistant",
+                            "content": [
+                                {"type": "thinking", "thinking": [{"type": "text", "text": "Thinking."}]},
+                                {"type": "text", "text": "Answer."},
+                            ],
+                        },
+                    }
+                ],
+                "usage": {"prompt_tokens": 5, "completion_tokens": 10, "total_tokens": 15},
+            }
+        )
         messages = _convert_mistral_response_to_chat_messages(json_str)
         assert len(messages) == 1
         assert messages[0].text == "Answer."

integrations/mistral/tests/test_mistral_chat_generator_async.py

@@ -1,4 +1,5 @@
 import json
+import logging
 import os
 from datetime import datetime
 from unittest.mock import AsyncMock, patch
@@ -318,15 +319,14 @@ async def test_run_async_empty_messages(self, monkeypatch):
 
     @pytest.mark.asyncio
     async def test_run_async_streaming_with_reasoning_logs_warning(self, monkeypatch, caplog):
-        import logging
+        monkeypatch.setenv("MISTRAL_API_KEY", "fake-api-key")
 
-        from haystack.components.generators.utils import print_streaming_chunk
-        from haystack.dataclasses import ChatMessage
+        async def async_callback(chunk: StreamingChunk):
+            pass
 
-        monkeypatch.setenv("MISTRAL_API_KEY", "fake-api-key")
         component = MistralChatGenerator(
             generation_kwargs={"reasoning_effort": "high"},
-            streaming_callback=print_streaming_chunk,
+            streaming_callback=async_callback,
         )
 
         with (