[Bugfix] Add fix for JSON whitespace (#4189)

Co-authored-by: Ubuntu <ubuntu@ip-172-31-13-147.ec2.internal>

tests/entrypoints/test_openai_server.py

@@ -754,6 +754,7 @@ async def test_guided_choice_chat_logprobs(server, client: openai.AsyncOpenAI,
 
 
 async def test_response_format_json_object(server, client: openai.AsyncOpenAI):
+    for _ in range(2):
         resp = await client.chat.completions.create(
             model=MODEL_NAME,
             messages=[{

vllm/model_executor/guided_decoding/outlines_logits_processors.py

@@ -131,6 +131,11 @@ class CFGLogitsProcessor(BaseLogitsProcessor):
         fsm = CFGFSM(cfg, tokenizer)
         self.fsm = fsm
 
+    def init_state(self):
+        """Initialize state with a CFGFSM copy."""
+        super().init_state()
+        self.fsm = self.fsm.copy()
+
 
 @lru_cache
 def _adapt_tokenizer(tokenizer: PreTrainedTokenizerBase):