[RL] Expose top-p-only sampling masks (#33593)

test/registered/unit/entrypoints/openai/test_protocol.py

@@ -124,6 +124,7 @@ class TestChatCompletionRequest(unittest.TestCase):
         self.assertEqual(request.messages[0].content, "Hello")
         self.assertEqual(request.temperature, None)  # default
         self.assertFalse(request.stream)  # default
+        self.assertFalse(request.return_sampling_mask)
         self.assertEqual(request.tool_choice, "none")  # default when no tools
 
     def test_image_content_hash_validation(self):

test/registered/unit/entrypoints/openai/test_serving_chat.py

@@ -278,9 +278,12 @@ class ServingChatTestCase(unittest.TestCase):
                 None,
             )
 
+            self.basic_req.return_sampling_mask = True
+            self.basic_req.return_meta_info = True
             adapted, processed = self.chat._convert_to_internal_request(self.basic_req)
             self.assertIsInstance(adapted, GenerateReqInput)
             self.assertFalse(adapted.stream)
+            self.assertTrue(adapted.return_sampling_mask)
             self.assertEqual(adapted.session_id, "session-1")
             self.assertEqual(processed, self.basic_req)
 
@@ -295,6 +298,18 @@ class ServingChatTestCase(unittest.TestCase):
             with self.subTest(field=field), self.assertRaisesRegex(ValueError, field):
                 self.chat._convert_to_internal_request(req, self.fastapi_request)
 
+    def test_validate_request_rejects_sampling_mask_without_meta_info(self):
+        req = ChatCompletionRequest(
+            model="x",
+            messages=[{"role": "user", "content": "Hi?"}],
+            return_sampling_mask=True,
+        )
+
+        self.assertEqual(
+            self.chat._validate_request(req),
+            "return_sampling_mask requires return_meta_info=true.",
+        )
+
     def test_convert_to_internal_request_rejects_stream_return_meta_info(self):
         req = ChatCompletionRequest(
             model="x",