buffers/thread: fix focus_next/prev_sibling

1 files changed, 11 insertions, 11 deletions

diff --git a/alot/buffers/thread.py b/alot/buffers/thread.py
index 052ed98d..b2d5f711 100644
--- a/alot/buffers/thread.py
+++ b/alot/buffers/thread.py
@@ -198,23 +198,23 @@ class ThreadBuffer(Buffer):
             new_focus = self.thread.message_list.index(msg.replies[-1])
             self.set_focus(new_focus)
 
+    def _focus_sibling(self, offset):
+        msg      = self.get_selected_message()
+        siblings = msg.parent.replies if msg.depth > 0 else self.thread.toplevel_messages
+        self_idx = siblings.index(msg)
+
+        new_idx = self_idx + offset
+        if new_idx >= 0 and new_idx < len(siblings):
+            self.set_focus(self.thread.message_list.index(siblings[new_idx]))
+
     def focus_next_sibling(self):
         """focus next sibling of currently focussed message in thread tree"""
-        pos_next = self.get_selected_message_position() + 1
-        depth = self.get_selected_message().depth
-        if (pos_next < self.thread.total_messages and
-            self.thread.message_list[pos_next].depth == depth):
-            self.set_focus(pos_next)
-
+        self._focus_sibling(1)
     def focus_prev_sibling(self):
         """
         focus previous sibling of currently focussed message in thread tree
         """
-        pos_next = self.get_selected_message_position() - 1
-        depth = self.get_selected_message().depth
-        if (pos_next < self.thread.total_messages and
-            self.thread.message_list[pos_next].depth == depth):
-            self.set_focus(pos_next)
+        self._focus_sibling(-1)
 
     def focus_next(self):
         """focus next message in depth first order"""