diff options
| -rw-r--r-- | tests/util/caches/test_descriptors.py | 33 |
1 files changed, 32 insertions, 1 deletions
diff --git a/tests/util/caches/test_descriptors.py b/tests/util/caches/test_descriptors.py index 48e616ac74..90861fe522 100644 --- a/tests/util/caches/test_descriptors.py +++ b/tests/util/caches/test_descriptors.py @@ -13,7 +13,7 @@ # See the License for the specific language governing permissions and # limitations under the License. import logging -from typing import Set +from typing import Iterable, Set, Tuple from unittest import mock from twisted.internet import defer, reactor @@ -1008,3 +1008,34 @@ class CachedListDescriptorTestCase(unittest.TestCase): obj.inner_context_was_finished, "Tried to restart a finished logcontext" ) self.assertEqual(current_context(), SENTINEL_CONTEXT) + + def test_num_args_mismatch(self): + """ + Make sure someone does not accidentally use @cachedList on a method with + a mismatch in the number args to the underlying single cache method. + """ + + class Cls: + @descriptors.cached(tree=True) + def fn(self, room_id, event_id): + pass + + # This is wrong ❌. `@cachedList` expects to be given the same number + # of arguments as the underlying cached function, just with one of + # the arguments being an iterable + @descriptors.cachedList(cached_method_name="fn", list_name="keys") + def list_fn(self, keys: Iterable[Tuple[str, str]]): + pass + + # Corrected syntax ✅ + # + # @cachedList(cached_method_name="fn", list_name="event_ids") + # async def list_fn( + # self, room_id: str, event_ids: Collection[str], + # ) + + obj = Cls() + + # Make sure this raises an error about the arg mismatch + with self.assertRaises(Exception): + obj.list_fn([("foo", "bar")]) |