test_concurrent_close should be sync only

test/asynchronous/test_change_stream.py

@@ -346,24 +346,25 @@ async def test_aggregate_cursor_blocks(self):
             self._test_next_blocks(change_stream)
 
     @no_type_check
-    async def test_concurrent_close(self):
-        """Ensure a AsyncChangeStream can be closed from another thread."""
+    @async_client_context.require_sync
+    def test_concurrent_close(self):
+        """Ensure a ChangeStream can be closed from another thread."""
         # Use a short wait time to speed up the test.
-        async with await self.change_stream(max_await_time_ms=250) as change_stream:
+        with self.change_stream(max_await_time_ms=250) as change_stream:
 
-            async def iterate_cursor():
+            def iterate_cursor():
                 try:
-                    async for _ in change_stream:
+                    for _ in change_stream:
                         pass
                 except OperationFailure as e:
                     if e.code != 237:  # AsyncCursorKilled error code
                         raise
 
             t = threading.Thread(target=iterate_cursor)
             t.start()
-            await self.watched_collection().insert_one({})
-            await asyncio.sleep(1)
-            await change_stream.close()
+            self.watched_collection().insert_one({})
+            asyncio.sleep(1)
+            change_stream.close()
             t.join(3)
             self.assertFalse(t.is_alive())
 

test/test_change_stream.py

@@ -342,6 +342,7 @@ def test_aggregate_cursor_blocks(self):
             self._test_next_blocks(change_stream)
 
     @no_type_check
+    @client_context.require_sync
     def test_concurrent_close(self):
         """Ensure a ChangeStream can be closed from another thread."""
         # Use a short wait time to speed up the test.