ruff: Fix PLW0108 Lambda may be unnecessary.

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Signed-off-by: Anders Kaseorg <anders@zulip.com>

tools/lib/capitalization.py

@@ -156,7 +156,7 @@ IGNORED_PHRASES = [
 
 # Sort regexes in descending order of their lengths. As a result, the
 # longer phrases will be ignored first.
-IGNORED_PHRASES.sort(key=lambda regex: len(regex), reverse=True)
+IGNORED_PHRASES.sort(key=len, reverse=True)
 
 # Compile regexes to improve performance. This also extracts the
 # text using BeautifulSoup and then removes extra whitespaces from

tools/test-backend

@@ -388,7 +388,7 @@ def main() -> None:
         if not options.no_cov_cleanup:
             import atexit
 
-            atexit.register(lambda: cov.erase())  # Ensure the data file gets cleaned up at the end.
+            atexit.register(cov.erase)  # Ensure the data file gets cleaned up at the end.
         cov.start()
     if options.profile:
         import cProfile

zerver/lib/bot_lib.py

@@ -42,8 +42,8 @@ class StateHandler:
 
     def __init__(self, user_profile: UserProfile) -> None:
         self.user_profile = user_profile
-        self.marshal: Callable[[object], str] = lambda obj: json.dumps(obj)
-        self.demarshal: Callable[[str], object] = lambda obj: json.loads(obj)
+        self.marshal: Callable[[object], str] = json.dumps
+        self.demarshal: Callable[[str], object] = json.loads
 
     def get(self, key: str) -> object:
         return self.demarshal(get_bot_storage(self.user_profile, key))

zerver/lib/cache_helpers.py

@@ -90,12 +90,12 @@ cache_fillers: Dict[
 ] = {
     "user": (get_users, user_cache_items, 3600 * 24 * 7, 10000),
     "client": (
-        lambda: Client.objects.all(),
+        Client.objects.all,
         client_cache_items,
         3600 * 24 * 7,
         10000,
     ),
-    "session": (lambda: Session.objects.all(), session_cache_items, 3600 * 24 * 7, 10000),
+    "session": (Session.objects.all, session_cache_items, 3600 * 24 * 7, 10000),
 }
 
 

zerver/lib/test_classes.py

@@ -1971,9 +1971,7 @@ class ZulipTestCase(ZulipTestCaseMixin, TestCase):
         # Some code might call process_notification using keyword arguments,
         # so mypy doesn't allow assigning lst.append to process_notification
         # So explicitly change parameter name to 'notice' to work around this problem
-        with mock.patch(
-            "zerver.tornado.event_queue.process_notification", lambda notice: lst.append(notice)
-        ):
+        with mock.patch("zerver.tornado.event_queue.process_notification", lst.append):
             # Some `send_event` calls need to be executed only after the current transaction
             # commits (using `on_commit` hooks). Because the transaction in Django tests never
             # commits (rather, gets rolled back after the test completes), such events would

zerver/tests/test_events.py

@@ -3345,7 +3345,7 @@ class NormalActionsTest(BaseAction):
             base = "/user_uploads/"
             self.assertEqual(base, url[: len(base)])
 
-        events = self.verify_action(lambda: do_upload(), num_events=1, state_change_expected=False)
+        events = self.verify_action(do_upload, num_events=1, state_change_expected=False)
 
         check_attachment_add("events[0]", events[0])
         self.assertEqual(events[0]["upload_space_used"], 6)
@@ -3481,21 +3481,21 @@ class NormalActionsTest(BaseAction):
 
     def test_restart_event(self) -> None:
         self.verify_action(
-            lambda: send_restart_events(),
+            send_restart_events,
             num_events=1,
             state_change_expected=False,
         )
 
     def test_web_reload_client_event(self) -> None:
         self.verify_action(
-            lambda: send_web_reload_client_events(),
+            send_web_reload_client_events,
             client_is_old=False,
             num_events=0,
             state_change_expected=False,
         )
         with self.assertLogs(level="WARNING") as logs:
             self.verify_action(
-                lambda: send_web_reload_client_events(),
+                send_web_reload_client_events,
                 client_is_old=True,
                 num_events=1,
                 state_change_expected=False,

zerver/tests/test_sessions.py

@@ -76,7 +76,7 @@ class TestSessions(ZulipTestCase):
     def test_delete_all_user_sessions(self) -> None:
         self.do_test_session(
             self.example_user("hamlet"),
-            lambda: delete_all_user_sessions(),
+            delete_all_user_sessions,
             get_realm("zulip"),
             True,
         )
@@ -90,7 +90,7 @@ class TestSessions(ZulipTestCase):
         )
         self.do_test_session(
             self.lear_user("cordelia"),
-            lambda: delete_all_user_sessions(),
+            delete_all_user_sessions,
             lear_realm,
             True,
         )

zerver/tests/test_timeout.py

@@ -34,7 +34,7 @@ class TimeoutTestCase(ZulipTestCase):
 
     def test_timeout_raises(self) -> None:
         try:
-            timeout(1, lambda: self.something_exceptional())
+            timeout(1, self.something_exceptional)
             raise AssertionError("Failed to raise an exception")
         except ValueError as exc:
             tb = traceback.format_tb(exc.__traceback__)

zerver/tornado/application.py

@@ -9,7 +9,7 @@ from zerver.tornado.handlers import AsyncDjangoHandler
 
 def setup_tornado_rabbitmq(queue_client: TornadoQueueClient) -> None:  # nocoverage
     # When tornado is shut down, disconnect cleanly from RabbitMQ
-    autoreload.add_reload_hook(lambda: queue_client.close())
+    autoreload.add_reload_hook(queue_client.close)
 
 
 def create_tornado_application(*, autoreload: bool = False) -> tornado.web.Application:

zerver/transaction_tests/test_user_groups.py

@@ -73,7 +73,7 @@ class UserGroupRaceConditionTestCase(ZulipTransactionTestCase):
         with transaction.atomic():
             for group in self.created_user_groups:
                 group.delete()
-            transaction.on_commit(lambda: self.created_user_groups.clear())
+            transaction.on_commit(self.created_user_groups.clear)
 
         super().tearDown()
 

zerver/worker/queue_processors.py

@@ -683,7 +683,7 @@ class MissedMessageWorker(QueueProcessingWorker):
     def start(self) -> None:
         with self.cv:
             self.stopping = False
-        self.worker_thread = threading.Thread(target=lambda: self.work())
+        self.worker_thread = threading.Thread(target=self.work)
         self.worker_thread.start()
         super().start()