[Model][Feat] Support Minimax-H3 quality grading requests through dynamic loading/unloading with Cache-DiT (#5853)

Signed-off-by: mglyn <1203789601@qq.com>

tests/diffusion/cache/test_cache_dit_request_runtime.py

@@ -0,0 +1,101 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+import pytest
+
+from vllm_omni.diffusion.cache.cachedit import runtime as runtime_module
+from vllm_omni.diffusion.cache.cachedit.runtime import (
+    CacheDiTRequestSpec,
+    RequestScopedCacheDiTRuntime,
+)
+from vllm_omni.diffusion.data import DiffusionCacheConfig
+
+pytestmark = [pytest.mark.core_model, pytest.mark.cpu, pytest.mark.diffusion]
+
+
+def _spec(key: str, steps: int = 50) -> CacheDiTRequestSpec:
+    return CacheDiTRequestSpec(
+        installation_key=key,
+        cache_config=DiffusionCacheConfig(),
+        num_inference_steps=steps,
+    )
+
+
+def _recording_backend(events):
+    class FakeBackend:
+        def __init__(self, config):
+            events.append(("create", config))
+            self.enabled = False
+
+        def enable(self, pipeline):
+            events.append(("enable", pipeline))
+            self.enabled = True
+
+        def refresh(self, pipeline, num_inference_steps):
+            events.append(("refresh", pipeline, num_inference_steps))
+
+        def disable(self, pipeline):
+            events.append(("disable", pipeline))
+            self.enabled = False
+
+        def is_enabled(self):
+            return self.enabled
+
+    return FakeBackend
+
+
+def test_startup_cache_follows_omit_lossless_high_omit_state_machine(monkeypatch):
+    events = []
+    FakeBackend = _recording_backend(events)
+    monkeypatch.setattr(runtime_module, "CacheDiTBackend", FakeBackend)
+    pipeline = object()
+    config = DiffusionCacheConfig()
+    runtime = RequestScopedCacheDiTRuntime(pipeline)
+    startup_backend = FakeBackend(config)
+    startup_backend.enabled = True
+
+    runtime.adopt(startup_backend, installation_key="generic")
+    runtime.prepare(_spec("generic", 50))  # omitted: keep startup cache
+    runtime.prepare(None)  # lossless: uninstall
+    runtime.prepare(None)  # repeated lossless: no-op
+    runtime.prepare(_spec("high", 40))  # high: install H3 profile
+    runtime.prepare(_spec("high", 30))  # repeated high: refresh only
+    runtime.prepare(_spec("generic", 20))  # omitted: restore startup profile
+
+    assert [event[0] for event in events] == [
+        "create",
+        "refresh",
+        "disable",
+        "create",
+        "enable",
+        "refresh",
+        "refresh",
+        "disable",
+        "create",
+        "enable",
+        "refresh",
+    ]
+    assert events[1][-1] == 50
+    assert events[5][-1] == 40
+    assert events[6][-1] == 30
+    assert events[10][-1] == 20
+    assert runtime.is_enabled
+
+
+def test_high_installs_without_startup_cache_and_lossless_uninstalls(monkeypatch):
+    events = []
+    monkeypatch.setattr(runtime_module, "CacheDiTBackend", _recording_backend(events))
+    pipeline = object()
+    runtime = RequestScopedCacheDiTRuntime(pipeline)
+
+    runtime.prepare(_spec("high", 40))
+    runtime.prepare(None)
+
+    assert [event[0] for event in events] == [
+        "create",
+        "enable",
+        "refresh",
+        "disable",
+    ]
+    assert events[2][-1] == 40
+    assert not runtime.is_enabled