[v1] add init plugin (#9716)

tests_v1/config/test_args_parser.py

@@ -24,7 +24,6 @@ def test_get_args_from_yaml(tmp_path: pathlib.Path):
         ### model
         model: "llamafactory/tiny-random-qwen2.5"
         trust_remote_code: true
-        use_fast_processor: true
         model_class: "llm"
         kernel_config:
           name: "auto"

tests_v1/conftest.py

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""LLaMA-Factory test configuration.
+"""LlamaFactory test configuration.
 
 Contains shared fixtures, pytest configuration, and custom markers.
 """
@@ -22,6 +22,7 @@ import sys
 
 import pytest
 import torch
+import torch.distributed as dist
 from pytest import Config, FixtureRequest, Item, MonkeyPatch
 
 from llamafactory.v1.accelerator.helper import get_current_accelerator, get_device_count
@@ -109,17 +110,24 @@ def _handle_device_visibility(items: list[Item]):
 def pytest_collection_modifyitems(config: Config, items: list[Item]):
     """Modify test collection based on markers and environment."""
     # Handle version compatibility (from HEAD)
-    if not is_transformers_version_greater_than("4.57.0"):
-        skip_bc = pytest.mark.skip(reason="Skip backward compatibility tests")
-        for item in items:
-            if "tests_v1" in str(item.fspath):
-                item.add_marker(skip_bc)
+    skip_bc = pytest.mark.skip(reason="Skip backward compatibility tests")
+    for item in items:
+        if "tests_v1" in str(item.fspath) and not is_transformers_version_greater_than("4.57.0"):
+            item.add_marker(skip_bc)
 
     _handle_slow_tests(items)
     _handle_runs_on(items)
     _handle_device_visibility(items)
 
 
+@pytest.fixture(autouse=True)
+def _cleanup_distributed_state():
+    """Cleanup distributed state after each test."""
+    yield
+    if dist.is_initialized():
+        dist.destroy_process_group()
+
+
 @pytest.fixture(autouse=True)
 def _manage_distributed_env(request: FixtureRequest, monkeypatch: MonkeyPatch) -> None:
     """Set environment variables for distributed tests if specific devices are requested."""
@@ -155,6 +163,7 @@ def _manage_distributed_env(request: FixtureRequest, monkeypatch: MonkeyPatch) -
             monkeypatch.setenv(env_key, visible_devices[0] if visible_devices else "0")
         else:
             monkeypatch.setenv(env_key, "0")
+
         if CURRENT_DEVICE == "cuda":
             monkeypatch.setattr(torch.cuda, "device_count", lambda: 1)
         elif CURRENT_DEVICE == "npu":

tests_v1/plugins/model_plugins/test_init_plugin.py

@@ -0,0 +1,56 @@
+# Copyright 2025 the LlamaFactory team.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import pytest
+
+from llamafactory.v1.accelerator.interface import DistributedInterface
+from llamafactory.v1.config.arg_parser import get_args
+from llamafactory.v1.core.model_loader import ModelLoader
+
+
+def test_init_on_meta():
+    _, model_args, *_ = get_args(
+        dict(
+            model="llamafactory/tiny-random-qwen2.5",
+            init_config={"name": "init_on_meta"},
+        )
+    )
+    model_loader = ModelLoader(model_args=model_args)
+    assert model_loader.model.device.type == "meta"
+
+
+@pytest.mark.runs_on(["cuda", "npu"])
+def test_init_on_rank0():
+    _, model_args, *_ = get_args(
+        dict(
+            model="llamafactory/tiny-random-qwen2.5",
+            init_config={"name": "init_on_rank0"},
+        )
+    )
+    model_loader = ModelLoader(model_args=model_args)
+    if DistributedInterface().get_rank() == 0:
+        assert model_loader.model.device.type == "cpu"
+    else:
+        assert model_loader.model.device.type == "meta"
+
+
+def test_init_on_default():
+    _, model_args, *_ = get_args(
+        dict(
+            model="llamafactory/tiny-random-qwen2.5",
+            init_config={"name": "init_on_default"},
+        )
+    )
+    model_loader = ModelLoader(model_args=model_args)
+    assert model_loader.model.device.type == DistributedInterface().current_accelerator.type