[Bug] extract_non_reasoning_content error when predict is null

Prerequisite

• I have searched Issues and Discussions but cannot get the expected help.
• The bug has not been fixed in the latest version.

Type

I'm evaluating with the officially supported tasks/models/datasets.

Environment

version 0.4.1

Reproduces the problem - code/configuration sample

from mmengine.config import read_base
from opencompass.models import OpenAISDK

with read_base():
    from opencompass.configs.datasets.math.math_500_gen import math_datasets



# pip install math_verify latex2sympy2_extended
# pip install langdetect
# opencompass eval_gsm8k.py
# opencompass opencompass/eval_ds3.py

datasets = math_datasets

from opencompass.utils.text_postprocessors import extract_non_reasoning_content

models = [
    dict(
        abbr='deepseek-r1-h800-32768',
        type=OpenAISDK,
        path='/root/.cache/huggingface',
        openai_api_base=['http://10.24.9.4:8000/v1'],
        # tokenizer_path='/opt/weights/DeepSeek-V3',
        key=
        'token-abc123',
        # meta_template=api_meta_template,
        # query_per_second=2,
        max_out_len=16384,
        max_seq_len=32768, # 32768
        temperature=0.6,
        batch_size=16,
        pred_postprocessor=dict(type=extract_non_reasoning_content),
        retry=10
        ),
]

Reproduces the problem - command or script

test math-500 using deepseek-r1 model

Reproduces the problem - error message

INFO 03-20 14:38:29 init.py:190] Automatically detected platform cuda.
03/20 14:38:30 - OpenCompass - INFO - Try to load the data from /home/wzp/.cache/opencompass/./data/math/
Traceback (most recent call last):
File "/cx8k/fs100/wzp/code/opencompass/opencompass/tasks/openicl_eval.py", line 475, in
inferencer.run()
File "/cx8k/fs100/wzp/code/opencompass/opencompass/tasks/openicl_eval.py", line 86, in run
self._score()
File "/cx8k/fs100/wzp/code/opencompass/opencompass/tasks/openicl_eval.py", line 179, in _score
pred_strs = [proc(s, **kwargs) for s in pred_strs]
File "/cx8k/fs100/wzp/code/opencompass/opencompass/tasks/openicl_eval.py", line 179, in
pred_strs = [proc(s, **kwargs) for s in pred_strs]
File "/cx8k/fs100/wzp/code/opencompass/opencompass/utils/text_postprocessors.py", line 278, in extract_non_reasoning_content
if think_start_token not in text and think_end_token in text:
TypeError: argument of type 'NoneType' is not iterable

Other information

No response