feat(tool call): Enhance Llama32Detector for improved JSON parsing in non-stream (#6784)

python/sglang/srt/function_call/llama32_detector.py

@@ -42,31 +42,41 @@ class Llama32Detector(BaseFormatDetector):
             return StreamingParseResult(normal_text=text, calls=[])
 
         if "<|python_tag|>" in text:
-            normal_text, action_text = text.split("<|python_tag|>")
+            normal_text, action_text = text.split("<|python_tag|>", maxsplit=1)
         else:
             normal_text, action_text = "", text
 
-        # Split by semicolon and process each part
-        json_parts = [
-            part.strip()
-            for part in action_text.split(self.tool_call_separator)
-            if part.strip()
-        ]
+        decoder = json.JSONDecoder()
+        idx = 0
+        safe_idx = idx  # the index of the last valid JSON object
         all_actions = []
-        for part in json_parts:
+        action_text_len = len(action_text)
+        while idx < action_text_len:
             try:
-                # Parse each individual JSON object
-                action = json.loads(part)
-                all_actions.append(action)
+                obj, end = decoder.raw_decode(action_text[idx:])
+                all_actions.append(obj)
+                idx += end + len(self.tool_call_separator)
+                safe_idx = idx
             except json.JSONDecodeError as e:
-                logger.warning(f"Failed to parse JSON part: {part}")
-                logger.warning(f"JSON parse error: {str(e)}")
+                # Find where next `{"name"` appears and try again
+                logger.warning(
+                    f"Failed to parse JSON part: {action_text[idx:]}, JSON parse error: {str(e)}"
+                )
+                next_obj_start = action_text.find('{"name":', idx + 1)
+                if next_obj_start == -1:
+                    break
+                idx = next_obj_start
                 continue
-        calls = []
+
         # Only process if we found valid JSON objects
-        if all_actions:
-            calls = self.parse_base_json(all_actions, tools)
-        return StreamingParseResult(normal_text=normal_text, calls=calls)
+        calls = self.parse_base_json(all_actions, tools) if all_actions else []
+        # Use safe_idx to avoid idx containing the last part of an invalid JSON object
+        trailing_text = (
+            action_text[safe_idx:].strip() if safe_idx < action_text_len else ""
+        )
+        return StreamingParseResult(
+            normal_text=normal_text + trailing_text, calls=calls
+        )
 
     def structure_info(self) -> _GetInfoFunc:
         return lambda name: StructureInfo(