refresh session whenever a reply succeeds

securedrop_client/gui/widgets.py

@@ -1572,6 +1572,12 @@ def __init__(
         self.setLayout(main_layout)
         self.update_conversation(self.source.collection)
 
+        # Refresh the session to update any replies that failed from a network timeout
+        self.controller.reply_succeeded.connect(self.refresh_conversation)
+
+    def refresh_conversation(self):
+        self.controller.session.refresh(self.source)
+
     def clear_conversation(self):
         while self.conversation_layout.count():
             child = self.conversation_layout.takeAt(0)

tests/gui/test_widgets.py

@@ -1363,6 +1363,19 @@ def test_ConversationView_init(mocker, homedir):
     assert isinstance(cv.conversation_layout, QVBoxLayout)
 
 
+def test_ConversationView_refresh_conversation(mocker, homedir):
+    """
+    Ensure that the session refreshes whenever there is a new reply in case there are previously
+    failed replies.
+    """
+    source = factory.Source()
+    cv = ConversationView(source, mocker.MagicMock())
+
+    cv.refresh_conversation()
+
+    cv.controller.session.refresh.assert_called_with(source)
+
+
 def test_ConversationView_update_conversation_position_follow(mocker, homedir):
     """
     Check the signal handler sets the correct value for the scrollbar to be