helper/model: Add footer notification for message sent outside narrow.

This commit generalizes the code for footer notification when a message
is sent/edited outside current narrow. This will give the user a pointer
as to why the message disappeared from the screen. The code is hooked to
the part where message request is sent to the server, hence preventing the
extra check for user_id being same as message_sender_id.

Tests amended.
Fixes #781.

tests/helper/test_helper.py

@@ -9,6 +9,7 @@
     hash_util_decode,
     index_messages,
     notify,
+    notify_if_message_sent_outside_narrow,
     powerset,
 )
 
@@ -309,6 +310,31 @@ def test_display_error_if_present(mocker, response, footer_updated):
         set_footer_text.assert_not_called()
 
 
+@pytest.mark.parametrize(['req', 'narrow', 'footer_updated'], [
+    ({'type': 'private', 'to': 'foo@gmail.com', 'content': 'bar'},
+     [['is', 'private']], False),
+    ({'type': 'private', 'to': 'bar@chat.zulip.com', 'content': 'foo'},
+     [['pm_with', 'foo@chat.zulip.com']], True),
+    ({'type': 'stream', 'to': 'ZT', 'subject': '1', 'content': 'foo'},
+     [['stream', 'ZT'], ['topic', '1']], False),
+    ({'type': 'stream', 'to': 'here', 'subject': 'pytest', 'content': 'py'},
+     [['stream', 'test here']], True)
+])
+def test_notify_if_message_sent_outside_narrow(mocker, req, narrow,
+                                               footer_updated):
+    controller = mocker.Mock()
+    set_footer_text = controller.view.set_footer_text
+    controller.model.narrow = narrow
+
+    notify_if_message_sent_outside_narrow(req, controller)
+
+    if footer_updated:
+        set_footer_text.assert_called_once_with(
+            'Message is sent outside of current narrow.', 3)
+    else:
+        set_footer_text.assert_not_called()
+
+
 @pytest.mark.parametrize('quoted_string, expected_unquoted_string', [
     ('(no.20topic)', '(no topic)'),
     ('.3Cstrong.3Exss.3C.2Fstrong.3E', '<strong>xss</strong>'),

tests/model/test_model.py

@@ -23,6 +23,8 @@ def mock_external_classes(self, mocker: Any) -> None:
         mocker.patch('zulipterminal.model.Model._start_presence_updates')
         self.display_error_if_present = mocker.patch(
                             'zulipterminal.model.display_error_if_present')
+        self.notify_if_message_sent_outside_narrow = mocker.patch(
+            'zulipterminal.model.notify_if_message_sent_outside_narrow')
 
     @pytest.fixture
     def model(self, mocker, initial_data, user_profile,
@@ -481,6 +483,9 @@ def test_send_private_message(self, mocker, model,
         assert result == return_value
         self.display_error_if_present.assert_called_once_with(response,
                                                               self.controller)
+        if result == 'success':
+            self.notify_if_message_sent_outside_narrow.assert_called_once_with(
+                req, self.controller)
 
     def test_send_private_message_with_no_recipients(self, model,
                                                      content="hi!",
@@ -507,6 +512,10 @@ def test_send_stream_message(self, mocker, model,
         self.display_error_if_present.assert_called_once_with(response,
                                                               self.controller)
 
+        if result == 'success':
+            self.notify_if_message_sent_outside_narrow.assert_called_once_with(
+                req, self.controller)
+
     @pytest.mark.parametrize('response, return_value', [
         ({'result': 'success'}, True),
         ({'result': 'some_failure'}, False),

zulipterminal/helper.py

@@ -651,6 +651,28 @@ def display_error_if_present(response: Dict[str, Any], controller: Any
         controller.view.set_footer_text(response['msg'], 3)
 
 
+def notify_if_message_sent_outside_narrow(request: Dict[str, Any],
+                                          controller: Any) -> None:
+    current_narrow = controller.model.narrow
+
+    if request['type'] == 'stream':
+        stream_narrow = [['stream', request['to']]]
+        topic_narrow = stream_narrow + [['topic', request['subject']]]
+
+        if (current_narrow != stream_narrow
+                and current_narrow != topic_narrow):
+            controller.view.set_footer_text(
+                'Message is sent outside of current narrow.', 3)
+    elif request['type'] == 'private':
+        pm_narrow = [['is', 'private']]
+        pm_with_narrow = [['pm_with', request['to']]]
+
+        if (current_narrow != pm_narrow
+                and current_narrow != pm_with_narrow):
+            controller.view.set_footer_text(
+                'Message is sent outside of current narrow.', 3)
+
+
 def hash_util_decode(string: str) -> str:
     """
     Returns a decoded string given a hash_util_encode() [present in

zulipterminal/model.py

@@ -37,6 +37,7 @@
     index_messages,
     initial_index,
     notify,
+    notify_if_message_sent_outside_narrow,
     set_count,
 )
 from zulipterminal.ui_tools.utils import create_msg_box_list
@@ -385,6 +386,9 @@ def send_private_message(self, recipients: List[str],
             }
             response = self.client.send_message(request)
             display_error_if_present(response, self.controller)
+            # FIXME: Is there a better way?
+            if response['result'] == 'success':
+                notify_if_message_sent_outside_narrow(request, self.controller)
             return response['result'] == 'success'
         else:
             raise RuntimeError('Empty recipients list.')
@@ -399,6 +403,8 @@ def send_stream_message(self, stream: str, topic: str,
         }
         response = self.client.send_message(request)
         display_error_if_present(response, self.controller)
+        if response['result'] == 'success':
+            notify_if_message_sent_outside_narrow(request, self.controller)
         return response['result'] == 'success'
 
     def update_private_message(self, msg_id: int, content: str) -> bool:
@@ -423,6 +429,13 @@ def update_stream_message(self, topic: str, message_id: int,
 
         response = self.client.update_message(request)
         display_error_if_present(response, self.controller)
+        if response['result'] == 'success':
+            old_topic = self.index['messages'][message_id].get('subject', None)
+            new_topic = request['topic']
+            view = self.controller.view
+            if old_topic != new_topic:
+                view.set_footer_text('Topic changed', 3)
+
         return response['result'] == 'success'
 
     def fetch_custom_emojis(self) -> NamedEmojiData: