fix: preserve wrapper-compatible compaction delegation

Author: HuxleyHu98

src/agents/memory/openai_responses_compaction_session.py

@@ -26,18 +26,36 @@
 OpenAIResponsesCompactionMode = Literal["previous_response_id", "input", "auto"]
 
 
-def _method_accepts_wrapper(method: Any) -> bool:
+def _method_signature(method: Any) -> tuple[inspect.Parameter, ...]:
     try:
-        parameters = tuple(inspect.signature(method).parameters.values())
+        return tuple(inspect.signature(method).parameters.values())
     except (TypeError, ValueError):
-        return False
+        return ()
+
+
 
+def _method_accepts_wrapper(method: Any) -> bool:
+    parameters = _method_signature(method)
     return any(
         parameter.kind is inspect.Parameter.VAR_KEYWORD or parameter.name == "wrapper"
         for parameter in parameters
     )
 
 
+
+def _method_accepts_limit(method: Any) -> bool:
+    parameters = _method_signature(method)
+    return any(
+        (
+            parameter.kind
+            in (inspect.Parameter.POSITIONAL_OR_KEYWORD, inspect.Parameter.KEYWORD_ONLY)
+            and parameter.name == "limit"
+        )
+        or parameter.kind is inspect.Parameter.VAR_KEYWORD
+        for parameter in parameters
+    )
+
+
 def select_compaction_candidate_items(
     items: list[TResponseInputItem],
 ) -> list[TResponseInputItem]:
@@ -255,8 +273,17 @@ async def get_items(
         limit: int | None = None,
         wrapper: RunContextWrapper[Any] | None = None,
     ) -> list[TResponseInputItem]:
-        if wrapper is not None and _method_accepts_wrapper(self.underlying_session.get_items):
-            return await self.underlying_session.get_items(limit, wrapper=wrapper)
+        accepts_wrapper = wrapper is not None and _method_accepts_wrapper(
+            self.underlying_session.get_items
+        )
+
+        if limit is None:
+            if accepts_wrapper:
+                return await self.underlying_session.get_items(wrapper=wrapper)
+            return await self.underlying_session.get_items()
+
+        if accepts_wrapper and _method_accepts_limit(self.underlying_session.get_items):
+            return await self.underlying_session.get_items(limit=limit, wrapper=wrapper)
         return await self.underlying_session.get_items(limit)
 
     async def _defer_compaction(self, response_id: str, store: bool | None = None) -> None:

tests/memory/test_openai_responses_compaction_session.py

@@ -107,6 +107,42 @@ def test_init_accepts_valid_model(self) -> None:
         )
         assert session.model == "gpt-4.1"
 
+    @pytest.mark.asyncio
+    async def test_get_items_preserves_legacy_wrapper_only_delegate_shape(self) -> None:
+        class WrapperOnlySession:
+            session_id = "test-session"
+
+            def __init__(self) -> None:
+                self.calls: list[tuple[int | None, Any]] = []
+
+            async def get_items(
+                self,
+                wrapper: Any = None,
+            ) -> list[TResponseInputItem]:
+                self.calls.append((None, wrapper))
+                return []
+
+            async def add_items(self, items: list[TResponseInputItem]) -> None:
+                return None
+
+            async def pop_item(self) -> TResponseInputItem | None:
+                return None
+
+            async def clear_session(self) -> None:
+                return None
+
+        underlying = cast(Session, WrapperOnlySession())
+        session = OpenAIResponsesCompactionSession(
+            session_id="test",
+            underlying_session=underlying,
+        )
+
+        wrapper = SimpleNamespace(context={"request_id": "abc"})
+        items = await session.get_items(wrapper=wrapper)
+
+        assert items == []
+        assert underlying.calls == [(None, wrapper)]
+
     @pytest.mark.asyncio
     async def test_add_items_delegates(self) -> None:
         mock_session = self.create_mock_session()