refactor: model: Use get_subscription_color instead of stream_dict.

This commit replaces the usage of directly indexing stream_dict for
"color" data with the new stream property accessor method
"get_subscription_color".

Test added.

Author: theViz343

tests/model/test_model.py

@@ -2279,6 +2279,21 @@ def test_get_stream_rendered_description(
         assert model.get_stream_rendered_description(stream_id) == expected_value
         model._get_stream_from_id.assert_called_once()
 
+    @pytest.mark.parametrize(
+        "stream_id, expected_value",
+        [
+            case(
+                1,
+                "#baf",
+            ),
+        ],
+    )
+    def test_get_subscription_color(
+        self, model, stream_dict, stream_id, expected_value
+    ):
+        model.stream_dict = stream_dict
+        assert model.get_subscription_color(stream_id) == expected_value
+
     def test_get_all_subscription_ids(
         self,
         model,

tests/ui_tools/test_boxes.py

@@ -1284,6 +1284,7 @@ def test__set_stream_write_box_style_markers(
     ) -> None:
         # FIXME: Refactor when we have ~ Model.is_private_stream
         write_box.model.stream_dict = stream_dict
+        write_box.model.get_subscription_color.return_value = expected_color
         write_box.model.is_valid_stream.return_value = is_valid_stream
         write_box.model.stream_id_from_name.return_value = stream_id
         write_box.model.stream_access_type.return_value = stream_access_type

tests/ui_tools/test_messages.py

@@ -951,13 +951,15 @@ def test_msg_generates_search_and_header_bar(
         msg_narrow,
         assert_header_bar,
         assert_search_bar,
+        stream_color="#bd6",
     ):
         self.model.stream_dict = {
             205: {
-                "color": "#bd6",
+                "color": stream_color,
             },
         }
         self.model.narrow = msg_narrow
+        self.model.get_subscription_color.return_value = stream_color
         messages = messages_successful_response["messages"]
         current_message = messages[msg_type]
         msg_box = MessageBox(current_message, self.model, messages[0])

zulipterminal/model.py

@@ -1236,6 +1236,13 @@ def get_stream_weekly_traffic(self, stream_id: int) -> Optional[int]:
     def get_stream_rendered_description(self, stream_id: int) -> str:
         return self._get_stream_from_id(stream_id)["rendered_description"]
 
+    def get_subscription_color(self, stream_id: int) -> Optional[str]:
+        if stream_id in self.stream_dict:
+            return self.stream_dict[stream_id]["color"]
+        elif stream_id in self._unsubscribed_streams:
+            return self._unsubscribed_streams[stream_id]["color"]
+        return None
+
     def _subscribe_to_streams(self, subscriptions: List[Subscription]) -> None:
         def make_reduced_stream_data(stream: Subscription) -> StreamData:
             # stream_id has been changed to id.

zulipterminal/ui_tools/boxes.py

@@ -412,8 +412,7 @@ def _set_stream_write_box_style(self, widget: ReadlineEdit, new_text: str) -> No
             stream_id = self.model.stream_id_from_name(new_text)
             stream_access_type = self.model.stream_access_type(stream_id)
             stream_marker = STREAM_ACCESS_TYPE[stream_access_type]["icon"]
-            stream = self.model.stream_dict[stream_id]
-            color = stream["color"]
+            color = self.model.get_subscription_color(stream_id)
         self.header_write_box[self.FOCUS_HEADER_PREFIX_STREAM].set_text(
             (color, stream_marker)
         )

zulipterminal/ui_tools/messages.py

@@ -150,7 +150,7 @@ def _is_private_message_to_self(self) -> bool:
 
     def stream_header(self) -> Any:
         assert self.stream_id is not None
-        color = self.model.stream_dict[self.stream_id]["color"]
+        color = self.model.get_subscription_color(self.stream_id)
         bar_color = f"s{color}"
         stream_title_markup = (
             "bar",
@@ -211,7 +211,7 @@ def top_search_bar(self) -> Any:
             text_to_fill = "Mentions"
         elif self.message["type"] == "stream":
             assert self.stream_id is not None
-            bar_color = self.model.stream_dict[self.stream_id]["color"]
+            bar_color = self.model.get_subscription_color(self.stream_id)
             bar_color = f"s{bar_color}"
             if len(curr_narrow) == 2 and curr_narrow[1][0] == "topic":
                 text_to_fill = (