feat: optional caller-supplied mm_hashes on GenerateReqInput (#25300)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: ishandhanani <82981111+ishandhanani@users.noreply.github.com>
2026-06-01 20:04:37 +02:00
parent f6a5a1b59c
commit 86afa21ca7
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+"""Tests for caller-supplied mm_hashes plumbing.
+
+Verifies the contract that:
+  1. GenerateReqInput.mm_hashes is an optional list of hex strings.
+  2. MultimodalDataItem.set_pad_value() honors a pre-set hash and does NOT
+     overwrite it via hash_feature().
+  3. The derived pad_value is deterministic across requests with identical
+     mm_hashes — the property external KV routers depend on.
+
+The wiring step that copies GenerateReqInput.mm_hashes into per-item
+MultimodalDataItem.hash lives in tokenizer_manager.py and is exercised by
+the e2e serve tests; this file pins the unit-level invariants the wiring
+relies on.
+"""
+
+import unittest
+from unittest.mock import patch
+
+from sglang.srt.managers.io_struct import GenerateReqInput
+from sglang.srt.managers.schedule_batch import (
+    Modality,
+    MultimodalDataItem,
+    _compute_pad_value,
+)
+from sglang.test.ci.ci_register import register_amd_ci, register_cuda_ci
+from sglang.test.test_utils import CustomTestCase
+
+register_cuda_ci(est_time=2, stage="base-b", runner_config="1-gpu-small")
+register_amd_ci(est_time=2, suite="stage-b-test-1-gpu-small-amd")
+
+
+class TestMmHashesContract(CustomTestCase):
+    def test_generate_req_input_accepts_mm_hashes(self):
+        """GenerateReqInput exposes mm_hashes as an optional field."""
+        req = GenerateReqInput(
+            text="hi",
+            image_data=["http://example.com/img.png"],
+            mm_hashes=["deadbeefcafe1234"],
+        )
+        self.assertEqual(req.mm_hashes, ["deadbeefcafe1234"])
+
+    def test_generate_req_input_defaults_mm_hashes_to_none(self):
+        """Absent mm_hashes preserves existing (None) behavior."""
+        req = GenerateReqInput(text="hi")
+        self.assertIsNone(req.mm_hashes)
+
+    def test_set_pad_value_honors_preset_hash(self):
+        """set_pad_value() must use a pre-set hash without recomputing."""
+        item = MultimodalDataItem(modality=Modality.IMAGE, hash=0xDEADBEEF)
+        # If hash_feature is invoked, the test fails — we patch it to
+        # raise so any accidental recompute is loud.
+        with patch(
+            "sglang.srt.managers.mm_utils.hash_feature",
+            side_effect=AssertionError(
+                "hash_feature must NOT be called when hash is preset"
+            ),
+        ):
+            item.set_pad_value()
+        self.assertEqual(item.hash, 0xDEADBEEF)
+        self.assertEqual(item.pad_value, _compute_pad_value(0xDEADBEEF))
+
+    def test_set_pad_value_is_deterministic_across_items(self):
+        """Two items with the same preset hash must derive the same pad_value."""
+        a = MultimodalDataItem(modality=Modality.IMAGE, hash=0x123456789ABCDEF0)
+        b = MultimodalDataItem(modality=Modality.IMAGE, hash=0x123456789ABCDEF0)
+        # No feature payload — set_pad_value uses the preset hash.
+        a.set_pad_value()
+        b.set_pad_value()
+        self.assertEqual(a.pad_value, b.pad_value)
+        self.assertEqual(a.hash, b.hash)
+
+    def test_set_pad_value_distinguishes_different_preset_hashes(self):
+        """Distinct preset hashes must produce distinct pad_values."""
+        a = MultimodalDataItem(modality=Modality.IMAGE, hash=0xAAAA)
+        b = MultimodalDataItem(modality=Modality.IMAGE, hash=0xBBBB)
+        a.set_pad_value()
+        b.set_pad_value()
+        self.assertNotEqual(a.pad_value, b.pad_value)
+
+
+if __name__ == "__main__":
+    unittest.main()