messages: Remove error handling for unreachable case.

Message type can only be "stream" or "private", as returned by the API.

Simplified the flow to bunch if-else blocks together.

Test removed.

Author: Niloth-p

tests/ui_tools/test_messages.py

@@ -65,12 +65,6 @@ def test_init(self, mocker, message_type, set_fields):
         assert msg_box.message_links == OrderedDict()
         assert msg_box.time_mentions == list()
 
-    def test_init_fails_with_bad_message_type(self):
-        message = dict(type="BLAH")
-
-        with pytest.raises(RuntimeError):
-            MessageBox(message, self.model, None)
-
     def test_private_message_to_self(self, mocker):
         message = dict(
             type="private",

zulipterminal/ui_tools/messages.py

@@ -81,13 +81,10 @@ def __init__(self, message: Message, model: "Model", last_message: Any) -> None:
             self.stream_name = self.message["display_recipient"]
             self.stream_id = self.message["stream_id"]
             self.topic_name = self.message["subject"]
-        elif self.message["type"] == "private":
+        else:
             self.email = self.message["sender_email"]
             self.user_id = self.message["sender_id"]
-        else:
-            raise RuntimeError("Invalid message type")
 
-        if self.message["type"] == "private":
             if self._is_private_message_to_self():
                 recipient = self.message["display_recipient"][0]
                 self.recipients_names = recipient["full_name"]