from zerver.lib.test_classes import ZulipTestCase class LegacySubjectTest(ZulipTestCase): def test_legacy_subject(self) -> None: self.login("hamlet") payload = dict( type="stream", to="Verona", content="Test message", ) payload["subject"] = "whatever" result = self.client_post("/json/messages", payload) self.assert_json_success(result) # You can't use both subject and topic. payload["topic"] = "whatever" result = self.client_post("/json/messages", payload) self.assert_json_error(result, "Can't decide between 'topic' and 'subject' arguments")