[model] add MOSS-VL support (#10708)

tests/data/test_mm_plugin.py

@@ -13,6 +13,7 @@
 # limitations under the License.
 
 import os
+from types import SimpleNamespace
 from typing import TYPE_CHECKING, Any
 
 import numpy as np
@@ -417,6 +418,24 @@ def test_qwen2_vl_plugin():
     _check_plugin(**check_inputs)
 
 
+def test_moss_vl_plugin():
+    messages = [
+        {"role": "user", "content": "First <image>, finally <image>."},
+        {"role": "assistant", "content": "Done."},
+    ]
+    expected_messages = [
+        {"role": "user", "content": "First <|image_pad|>, finally <|image_pad|>."},
+        {"role": "assistant", "content": "Done."},
+    ]
+    processor = SimpleNamespace(image_processor=object(), video_processor=object())
+    plugin = get_mm_plugin(name="moss_vl", image_token="<|image_pad|>", video_token="<|video_pad|>")
+
+    processed_messages = plugin.process_messages(messages, [object(), object()], [], [], processor)
+
+    assert processed_messages == expected_messages
+    assert messages[0]["content"] == "First <image>, finally <image>."
+
+
 @pytest.mark.runs_on(["cpu", "mps"])
 @pytest.mark.skipif(not is_transformers_version_greater_than("4.57.0"), reason="Requires transformers>=4.57.0")
 def test_qwen3_vl_plugin():