[Bugfix][Examples][MammothModa2] Serve T2I via LLM-typed DiT stage (#7199) + benchmark harness and profiler wiring (#7293)

Signed-off-by: quan-yi-ai <82917002+quan-yi-ai@users.noreply.github.com>
Co-authored-by: Hongsheng Liu <liuhongsheng4@huawei.com>

tests/examples/offline_inference/test_text_to_image_cli_forwarding.py

@@ -0,0 +1,140 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
+
+"""
+Offline inference regression tests: explicit CLI parallel-knob forwarding.
+
+Covers the argparse defaults -> ``build_parallel_knob_kwargs`` -> ``main()``'s
+``omni_kwargs`` assembly in examples/offline_inference/text_to_image/text_to_image.py.
+Three invariants:
+
+1. The shipped argparse must default the parallel knobs to ``None`` so unset
+   flags do not enter ``omni_kwargs`` and a deploy YAML value stays in effect.
+2. Explicitly supplied values equal to the old argparse defaults (e.g.
+   ``--ulysses-degree 1``, ``--ulysses-mode strict``) must still be forwarded
+   so they can override the deploy YAML, instead of being silently dropped
+   (review feedback on PR #7293).
+3. The AR grid ``max_tokens`` budget must stay owned by the shared
+   ``ar_grid_max_tokens`` helper used by both this example and the online
+   serving path (review feedback on PR #7293).
+
+Both invariants are asserted against the real script (its ``parse_args()`` and
+its ``build_parallel_knob_kwargs``), not a re-implemented copy. Invariant 3 is
+asserted directly against ``ar_grid_max_tokens`` itself.
+"""
+
+import sys
+from pathlib import Path
+
+import pytest
+
+_script_dir = str(Path(__file__).parent.parent.parent.parent / "examples" / "offline_inference" / "text_to_image")
+sys.path.insert(0, _script_dir)
+
+pytestmark = [pytest.mark.core_model, pytest.mark.cpu]
+
+_KNOBS = (
+    "ulysses_degree",
+    "ulysses_mode",
+    "ring_degree",
+    "cfg_parallel_size",
+    "vae_patch_parallel_size",
+)
+
+
+def _parse_real_args(cli_flags: list[str]):
+    """Run the example's real argparse against a synthetic argv."""
+    import text_to_image as t2i
+
+    saved = sys.argv
+    sys.argv = ["text_to_image.py", *cli_flags]
+    try:
+        return t2i.parse_args()
+    finally:
+        sys.argv = saved
+
+
+class TestParallelKnobForwarding:
+    """Drive the example's real argparse + real forwarding helper."""
+
+    def test_unset_knobs_forward_nothing(self):
+        """No CLI flags -> no keys, so the deploy YAML values stay in effect."""
+        import text_to_image as t2i
+
+        args = _parse_real_args([])
+        assert t2i.build_parallel_knob_kwargs(args) == {}
+
+    def test_explicit_default_equivalent_values_are_forwarded(self):
+        """--ulysses-degree 1 / --ulysses-mode strict must override the YAML."""
+        import text_to_image as t2i
+
+        args = _parse_real_args(["--ulysses-degree", "1", "--ulysses-mode", "strict"])
+        assert t2i.build_parallel_knob_kwargs(args) == {
+            "ulysses_degree": 1,
+            "ulysses_mode": "strict",
+        }
+
+        args = _parse_real_args(["--ring-degree", "1", "--cfg-parallel-size", "1", "--vae-patch-parallel-size", "1"])
+        assert t2i.build_parallel_knob_kwargs(args) == {
+            "ring_degree": 1,
+            "cfg_parallel_size": 1,
+            "vae_patch_parallel_size": 1,
+        }
+
+    def test_non_default_values_are_forwarded(self):
+        import text_to_image as t2i
+
+        args = _parse_real_args(
+            [
+                "--ulysses-degree",
+                "2",
+                "--ulysses-mode",
+                "advanced_uaa",
+                "--ring-degree",
+                "2",
+                "--cfg-parallel-size",
+                "2",
+                "--vae-patch-parallel-size",
+                "2",
+            ]
+        )
+        assert t2i.build_parallel_knob_kwargs(args) == {
+            "ulysses_degree": 2,
+            "ulysses_mode": "advanced_uaa",
+            "ring_degree": 2,
+            "cfg_parallel_size": 2,
+            "vae_patch_parallel_size": 2,
+        }
+
+    def test_script_defaults_are_none(self):
+        """The shipped argparse must default to None so unset == defer to YAML."""
+        import text_to_image as t2i
+
+        parser = t2i.build_parser()
+        defaults = {key: parser.get_default(key) for key in _KNOBS}
+        assert defaults == {key: None for key in _KNOBS}
+
+
+class TestARGridMaxTokens:
+    """The AR grid budget formula must stay shared between serving and offline.
+
+    ``ar_grid_max_tokens`` (vllm_omni.diffusion.utils.param_utils) is the
+    single owner of the ``ar_height * (ar_width + 1) + 1`` contract used by
+    both the online serving path (serving_chat.py) and this example script,
+    so a grid-contract change cannot desynchronize one copy (review feedback
+    on PR #7293).
+    """
+
+    def test_grid_budget_matches_formula(self):
+        from vllm_omni.diffusion.utils.param_utils import ar_grid_max_tokens
+
+        assert ar_grid_max_tokens(64, 64) == 64 * 65 + 1
+        assert ar_grid_max_tokens(32, 48) == 48 * 33 + 1
+
+    def test_grid_budget_none_for_absent_or_invalid_grid(self):
+        from vllm_omni.diffusion.utils.param_utils import ar_grid_max_tokens
+
+        # Callers treat None as "keep the existing max_tokens default".
+        assert ar_grid_max_tokens(0, 0) is None
+        assert ar_grid_max_tokens(0, 64) is None
+        assert ar_grid_max_tokens(64, 0) is None