model/boxes/messages: Add subscription_color_from_id method to model.

This commit introduces the subscription_color_from_id method in
order to limit the direct accessing of stream_dict outside
the model. The commit also replaces the access of the color
attribute from stream_dict with the new method.

Tests added and updated.

Author: theViz343

tests/model/test_model.py

@@ -1936,6 +1936,24 @@ def test_get_all_stream_ids(
     def test_stream_name_from_id(self, model, stream_id, expected_stream_name):
         assert model.stream_name_from_id(stream_id) == expected_stream_name
 
+    @pytest.mark.parametrize(
+        "stream_id, expected_stream_color",
+        [
+            case(
+                1000,
+                "#baf",
+                id="Subscribed stream",
+            ),
+            case(
+                999,
+                "#ddd",
+                id="Unsubscribed stream",
+            ),
+        ],
+    )
+    def test_subscription_color_from_id(self, model, stream_id, expected_stream_color):
+        assert model.subscription_color_from_id(stream_id) == expected_stream_color
+
     @pytest.mark.parametrize("muted", powerset([99, 1000]))
     @pytest.mark.parametrize("visual_notification_enabled", powerset([99, 1000]))
     def test__subscribe_to_streams(

tests/ui_tools/test_boxes.py

@@ -1282,7 +1282,9 @@ def test__set_stream_write_box_style_markers(
         expected_color: str,
     ) -> None:
         # FIXME: Refactor when we have ~ Model.is_private_stream
-        write_box.model.stream_dict = stream_dict
+        write_box.model.subscription_color_from_id.side_effect = lambda x: stream_dict[
+            x
+        ]["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

@@ -1005,11 +1005,7 @@ def test_msg_generates_search_and_header_bar(
         assert_header_bar,
         assert_search_bar,
     ):
-        self.model.stream_dict = {
-            205: {
-                "color": "#bd6",
-            },
-        }
+        self.model.subscription_color_from_id.return_value = "#bd6"
         self.model.narrow = msg_narrow
         messages = messages_successful_response["messages"]
         current_message = messages[msg_type]

zulipterminal/model.py

@@ -1311,6 +1311,10 @@ def stream_name_from_id(self, stream_id: int) -> str:
         stream = self._get_stream_from_id(stream_id)
         return stream["name"]
 
+    def subscription_color_from_id(self, subscription_id: int) -> str:
+        subscription = self._get_subscription_from_id(subscription_id)
+        return subscription["color"]
+
     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.subscription_color_from_id(stream_id)
         self.header_write_box[self.FOCUS_HEADER_PREFIX_STREAM].set_text(
             (color, stream_marker)
         )

zulipterminal/ui_tools/messages.py

@@ -152,7 +152,7 @@ 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.subscription_color_from_id(self.stream_id)
         bar_color = f"s{color}"
         stream_access_type = self.model.stream_access_type(self.stream_id)
         stream_icon = STREAM_ACCESS_TYPE[stream_access_type]["icon"]
@@ -220,7 +220,7 @@ 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.subscription_color_from_id(self.stream_id)
             bar_color = f"s{bar_color}"
             if len(curr_narrow) == 2 and curr_narrow[1][0] == "topic":
                 text_to_fill = (