Fix flaky LangGraph timeout tests

The test activities slept for 1s with a 100ms start_to_close_timeout.
Since Temporal does not actively cancel an activity when
start_to_close_timeout fires (it just rejects late completions), the
server processing the activity completion raced with it processing the
timeout, and on slow runners (Windows CI) the completion sometimes
won — causing test_timeout to fail with "DID NOT RAISE
WorkflowFailureError".

Increase the activity sleep to 30s so the timer reliably fires long
before the activity could complete naturally. Worker-shutdown
cancellation cleans up the still-sleeping activity when the test exits
its `async with Worker(...)` block, so runtime is unchanged.

Same fix applied to slow_task, used by the otherwise-identical pattern
in test_per_task_activity_options_override.

Author: DABH

tests/contrib/langgraph/e2e_functional_entrypoints.py

@@ -134,7 +134,12 @@ async def interrupt_entrypoint(value: str) -> dict:
 
 @task
 async def slow_task(x: int) -> int:
-    await asyncio.sleep(1)
+    # Sleep much longer than the start_to_close_timeout used by tests that
+    # exercise this task's timeout path. Temporal does not actively cancel
+    # an activity when start_to_close_timeout fires; it just rejects late
+    # completions, so a short sleep races with the activity completing
+    # before the server processes the timeout.
+    await asyncio.sleep(30)
     return x
 
 

tests/contrib/langgraph/test_timeout.py

@@ -19,7 +19,11 @@ class State(TypedDict):
 
 
 async def node(state: State) -> dict[str, str]:  # pyright: ignore[reportUnusedParameter]
-    await sleep(1)  # 1 second
+    # Sleep much longer than the start_to_close_timeout below: Temporal does
+    # not actively cancel an activity when start_to_close_timeout fires, it
+    # just rejects late completions. A short sleep races with the server
+    # processing the completion vs. the timeout, which flakes on slow CI.
+    await sleep(30)
     return {"value": "done"}