model: Add event handling for realm emoji.

This commit adds event handler for update of realm emoji within a
ZT session. The generate_all_emoji_data() function unpacks the three
emoji dictionaries in the priority order given by
zulip extra emoji>realm emoji>unicode emoji

Tests added.

Fixes #809

Author: mkp6781

tests/model/test_model.py

@@ -183,6 +183,7 @@ def test_register_initial_desired_events(self, mocker, initial_data):
             'subscription',
             'typing',
             'update_message_flags',
+            'realm_emoji',
         ]
         fetch_event_types = [
             'realm',
@@ -2015,6 +2016,46 @@ def test_user_name_from_id_invalid(self, model, user_id):
         with pytest.raises(RuntimeError, match='Invalid user ID.'):
             model.user_name_from_id(user_id)
 
+    @pytest.mark.parametrize('response', [
+        ({
+            "last_event_id": -1,
+            "type": "realm_emoji",
+            "msg": "",
+            "queue_id": "1517975029:0",
+            "realm_emoji": {
+                "100": {
+                    "id": "100",
+                    "name": "urwid",
+                    "deactivated": True
+                },
+                "1": {
+                    "id": "1",
+                    "name": "green_tick",
+                    "deactivated": False
+                },
+                "202020": {
+                    "id": "202020",
+                    "name": "joker",
+                    "deactivated": True
+                },
+            },
+            "result": "success",
+            "zulip_feature_level": 2,
+            "zulip_version": "2.1.0"
+        })
+    ])
+    def test__handle_update_emoji_event(self, mocker, model,
+                                        response):
+        model._handle_update_emoji_event(response)
+        # For an already active emoji which has been deactivated
+        with pytest.raises(KeyError):
+            model.active_emoji_data['urwid']
+        # For a newly created custom emoji.
+        new_added_emoji = model.active_emoji_data['green_tick']['code']
+        assert new_added_emoji == response['realm_emoji']['1']['id']
+        # For deactivated custom emoji with same name as unicode emoji
+        assert model.active_emoji_data['joker']['type'] == 'unicode_emoji'
+
     # Use LoopEnder with raising_event to cause the event loop to end without
     # processing the event
     class LoopEnder(Exception):

zulipterminal/api_types.py

@@ -107,11 +107,17 @@ class UpdateMessageFlagsEvent(TypedDict):
     all: bool
 
 
+class UpdateRealmEmojiEvent(TypedDict):
+    type: Literal['realm_emoji']
+    realm_emoji: Dict[str, Any]
+
+
 Event = Union[
     MessageEvent,
     UpdateMessageEvent,
     ReactionEvent,
     SubscriptionEvent,
     TypingEvent,
     UpdateMessageFlagsEvent,
+    UpdateRealmEmojiEvent,
 ]

zulipterminal/model.py

@@ -89,6 +89,7 @@ def __init__(self, controller: Any) -> None:
                 ('typing', self._handle_typing_event),
                 ('update_message_flags',
                  self._handle_update_message_flags_event),
+                ('realm_emoji', self._handle_update_emoji_event),
             ])
         )
 
@@ -1149,6 +1150,14 @@ def formatted_local_time(self, timestamp: int,
         else:
             return local_time.strftime('%a %b %d %H:%M')
 
+    def _handle_update_emoji_event(self, event: Event) -> None:
+        """
+        Handle update of emoji
+        """
+        assert event['type'] == "realm_emoji"
+        self.active_emoji_data = self.generate_all_emoji_data(
+                                                    event['realm_emoji'])
+
     def _update_rendered_view(self, msg_id: int) -> None:
         """
         Helper method called by various _handle_* methods