test(integration): tencent thinking reaches the provider body instead of failing the request (Pylon #7834)

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

tests/integration/contracts.json

@@ -223,6 +223,12 @@
     "tests/integration/providers/test_xiaomi_mimo_wire.py::test_xiaomi_mimo_tool_call_is_forwarded_and_returned": [
       "other.provider_wire.xiaomi_mimo.tool_call_survives_translation"
     ],
+    "tests/integration/providers/test_tencent_chat_wire.py::test_tencent_thinking_is_sent_in_provider_body_instead_of_failing_the_request[thinking_enabled]": [
+      "other.provider_wire.tencent.thinking_reaches_provider_in_request_body"
+    ],
+    "tests/integration/providers/test_tencent_chat_wire.py::test_tencent_thinking_is_sent_in_provider_body_instead_of_failing_the_request[reasoning_effort_none]": [
+      "other.provider_wire.tencent.thinking_reaches_provider_in_request_body"
+    ],
     "tests/integration/providers/test_fal_ai_video_wire.py::test_fal_h3_video_create_uses_canonical_body_and_status_path": [
       "other.provider_wire.fal_ai.video_queue_create_status_and_content_download"
     ],

tests/integration/providers/test_tencent_chat_wire.py

@@ -0,0 +1,86 @@
+import json
+import uuid
+from typing import Final
+
+import pytest
+from integration._support.client import Gateway
+from integration._support.wire import Reply, Request, wire_server
+from pydantic import JsonValue, TypeAdapter
+
+_BACKEND: Final = "deepseek-v4-pro"
+_API_KEY: Final = "synthetic-tencent-key"
+_PROMPT: Final = "What is 17 + 26? Answer with just the number."
+_JSON_OBJECT: Final = TypeAdapter(dict[str, JsonValue])
+_REASONING_REQUESTS: Final[tuple[tuple[str, dict[str, JsonValue], dict[str, JsonValue]], ...]] = (
+    ("thinking_enabled", {"thinking": {"type": "enabled"}}, {"type": "enabled"}),
+    ("reasoning_effort_none", {"reasoning_effort": "none"}, {"type": "disabled"}),
+)
+
+
+def _completion(identity: str) -> bytes:
+    return json.dumps(
+        {
+            "id": identity,
+            "object": "chat.completion",
+            "created": 1,
+            "model": _BACKEND,
+            "choices": [
+                {
+                    "index": 0,
+                    "message": {"role": "assistant", "content": "43", "reasoning_content": "17 plus 26 is 43."},
+                    "finish_reason": "stop",
+                }
+            ],
+            "usage": {"prompt_tokens": 23, "completion_tokens": 41, "total_tokens": 64},
+        }
+    ).encode()
+
+
+@pytest.mark.covers("other.provider_wire.tencent.thinking_reaches_provider_in_request_body")
+@pytest.mark.parametrize(
+    ("reasoning_params", "expected_thinking"),
+    tuple(case[1:] for case in _REASONING_REQUESTS),
+    ids=tuple(case[0] for case in _REASONING_REQUESTS),
+)
+def test_tencent_thinking_is_sent_in_provider_body_instead_of_failing_the_request(
+    gateway: Gateway, reasoning_params: dict[str, JsonValue], expected_thinking: dict[str, JsonValue]
+) -> None:
+    identity: Final = f"tencent-thinking-{uuid.uuid4().hex}"
+
+    def respond(request: Request) -> Reply:
+        assert request.method == "POST"
+        assert request.target == "/chat/completions"
+        assert request.headers["authorization"] == f"Bearer {_API_KEY}"
+        assert request.headers["content-type"] == "application/json"
+        assert _JSON_OBJECT.validate_json(request.body) == {
+            "model": _BACKEND,
+            "messages": [{"role": "user", "content": _PROMPT}],
+            "thinking": expected_thinking,
+        }
+        return Reply(body=_completion(identity))
+
+    with wire_server(respond) as wire, gateway.scenario() as scenario:
+        model: Final = scenario.model(model=f"tencent/{_BACKEND}", api_base=wire.url, api_key=_API_KEY)
+        response: Final = gateway.request(
+            "POST",
+            "/v1/chat/completions",
+            {"model": model, "messages": [{"role": "user", "content": _PROMPT}], **reasoning_params},
+        )
+        assert response.status_code == 200, response.text
+        payload: Final = _JSON_OBJECT.validate_json(response.content)
+        assert payload["id"] == identity
+        assert payload["choices"] == [
+            {
+                "finish_reason": "stop",
+                "index": 0,
+                "message": {
+                    "role": "assistant",
+                    "content": "43",
+                    "reasoning_content": "17 plus 26 is 43.",
+                    "provider_specific_fields": {"refusal": None},
+                },
+                "provider_specific_fields": {},
+            }
+        ]
+        assert payload["usage"] == {"prompt_tokens": 23, "completion_tokens": 41, "total_tokens": 64}
+        assert [(request.method, request.target) for request in wire.drain()] == [("POST", "/chat/completions")]