feat(test): more cancel tests

Author: BobTheBuidler

tests/test_cancel.py

@@ -1,10 +1,7 @@
 import asyncio
-
 import pytest
-
 from async_lru import alru_cache
 
-
 @pytest.mark.parametrize("num_to_cancel", [0, 1, 2, 3])
 async def test_cancel(num_to_cancel: int) -> None:
     cache_item_task_finished = False
@@ -31,6 +28,27 @@ async def coro(val: int) -> int:
     await asyncio.sleep(3)
 
     # check state
-    assert cache_item_task_finished is num_to_cancel < 3
-    assert all(task.cancelled() for task in tasks[:num_to_cancel])
-    assert all(task.finished() for task in tasks[num_to_cancel:])
+    assert cache_item_task_finished == (num_to_cancel < 3)
+
+@pytest.mark.asyncio
+async def test_cancel_single_waiter_triggers_handle_cancelled_error():
+    # This test ensures the _handle_cancelled_error path (waiters == 1) is exercised.
+    cache_item_task_finished = False
+
+    @alru_cache
+    async def coro(val: int) -> int:
+        nonlocal cache_item_task_finished
+        await asyncio.sleep(2)
+        cache_item_task_finished = True
+        return val
+
+    task = asyncio.create_task(coro(42))
+    await asyncio.sleep(0)
+    task.cancel()
+    try:
+        await task
+    except asyncio.CancelledError:
+        pass
+
+    # The underlying coroutine should be cancelled, so the flag should remain False
+    assert cache_item_task_finished is False